version 3.0.2

* NEWS: Record release date.

.gitignore

@@ -1,7 +1,16 @@
+*.eps
+*.log
+*.o
+*.pdf
+*.png
+*.stamp
+*.trs
+*~
+.deps
+.dirstamp
 /*.cache
 /*.flc
 /*.prj
-/*~
 /.tarball-version
 /.version
 /ABOUT-NLS

.prev-version

@@ -1 +1 @@
-2.7
+3.0.1

Makefile.am

@@ -32,8 +32,8 @@ EXTRA_DIST = .prev-version .version \
 ## version of Bison nearby...
 BISON = $(top_builddir)/tests/bison
 BISON_IN = $(top_srcdir)/tests/bison.in
-YACC = $(BISON) -y
-AM_YFLAGS = -d -v --warnings=all,error --report=all
+YACC = $(BISON) -o y.tab.c
+AM_YFLAGS = -d -v -Werror -Wall -Wno-yacc --report=all
 
 # Initialization before completion by local.mk's.
 AM_CFLAGS = $(WARN_CFLAGS)
@@ -78,11 +78,11 @@ dist-hook: gen-ChangeLog
 
 .PHONY: update-b4-copyright update-package-copyright-year
 update-b4-copyright:
-	find $(srcdir)/data -type f          \
+	$(AM_V_GEN)find $(srcdir)/data -type f          \
 	  | xargs $(srcdir)/build-aux/$@
 	@echo 'warning: src/parse-gram.[hc] may need to be regenerated.'
 update-package-copyright-year:
-	$(srcdir)/build-aux/$@ $(srcdir)/configure.ac
+	$(AM_V_GEN)$(srcdir)/build-aux/$@ $(srcdir)/configure.ac
 
 gen_start_date = 2012-01-16
 .PHONY: gen-ChangeLog

NEWS

@@ -1,17 +1,64 @@
 GNU Bison NEWS
 
-* Noteworthy changes in release ?.? (????-??-??) [?]
+* Noteworthy changes in release 3.0.2 (2013-12-05) [stable]
+
+** Bug fixes
+
+*** Generated source files when errors are reported
+
+  When warnings are issued and -Werror is set, bison would still generate
+  the source files (*.c, *.h...).  As a consequence, some runs of "make"
+  could fail the first time, but not the second (as the files were generated
+  anyway).
+
+  This is fixed: bison no longer generates this source files, but, of
+  course, still produces the various reports (*.output, *.xml, etc.).
+
+*** %empty is used in reports
+
+  Empty right-hand sides are denoted by '%empty' in all the reports (text,
+  dot, XML and formats derived from it).
+
+*** YYERROR and variants
+
+  When C++ variant support is enabled, an error triggered via YYERROR, but
+  not caught via error recovery, resulted in a double deletion.
+
+* Noteworthy changes in release 3.0.1 (2013-11-12) [stable]
+
+** Bug fixes
+
+*** Errors in caret diagnostics
+
+  On some platforms, some errors could result in endless diagnostics.
+
+*** Fixes of the -Werror option
+
+  Options such as "-Werror -Wno-error=foo" were still turning "foo"
+  diagnostics into errors instead of warnings.  This is fixed.
+
+  Actually, for consistency with GCC, "-Wno-error=foo -Werror" now also
+  leaves "foo" diagnostics as warnings.  Similarly, with "-Werror=foo
+  -Wno-error", "foo" diagnostics are now errors.
+
+*** GLR Predicates
+
+  As demonstrated in the documentation, one can now leave spaces between
+  "%?" and its "{".
+
+*** Installation
+
+  The yacc.1 man page is no longer installed if --disable-yacc was
+  specified.
+
+*** Fixes in the test suite
+
+  Bugs and portability issues.
+
+* Noteworthy changes in release 3.0 (2013-07-25) [stable]
 
 ** WARNING: Future backward-incompatibilities!
 
-  Bison will stop adding a semicolon at the end of the actions (as announced
-  in the release 2.5):
-
-    foo.y:2.22: warning: a ';' might be needed at the end of action code
-     exp: "num" { $$ = $1 }
-                          ^
-    foo.y:2.22:     future versions of Bison will not add the ';'
-
   Like other GNU packages, Bison will start using some of the C99 features
   for its own code, especially the definition of variables after statements.
   The generated C parsers still aim at C90.
@@ -28,9 +75,32 @@ GNU Bison NEWS
   Support for YYLEX_PARAM and YYPARSE_PARAM is removed (deprecated in Bison
   1.875): use %lex-param, %parse-param, or %param.
 
+  Missing semicolons at the end of actions are no longer added (as announced
+  in the release 2.5).
+
+*** Use of YACC='bison -y'
+
+  TL;DR: With Autoconf <= 2.69, pass -Wno-yacc to (AM_)YFLAGS if you use
+  Bison extensions.
+
+  Traditional Yacc generates 'y.tab.c' whatever the name of the input file.
+  Therefore Makefiles written for Yacc expect 'y.tab.c' (and possibly
+  'y.tab.h' and 'y.outout') to be generated from 'foo.y'.
+
+  To this end, for ages, AC_PROG_YACC, Autoconf's macro to look for an
+  implementation of Yacc, was using Bison as 'bison -y'.  While it does
+  ensure compatible output file names, it also enables warnings for
+  incompatibilities with POSIX Yacc.  In other words, 'bison -y' triggers
+  warnings for Bison extensions.
+
+  Autoconf 2.70+ fixes this incompatibility by using YACC='bison -o y.tab.c'
+  (which also generates 'y.tab.h' and 'y.output' when needed).
+  Alternatively, disable Yacc warnings by passing '-Wno-yacc' to your Yacc
+  flags (YFLAGS, or AM_YFLAGS with Automake).
+
 ** Bug fixes
 
-*** The epilogue is no longer affected by internal #defines
+*** The epilogue is no longer affected by internal #defines (glr.c)
 
   The glr.c skeleton uses defines such as #define yylval (yystackp->yyval) in
   generated code.  These weren't properly undefined before the inclusion of
@@ -39,7 +109,7 @@ GNU Bison NEWS
 
     int yylex (YYSTYPE *yylval);
 
-  This is has been fixed: yylval, yynerrs, yychar, and yylloc are now valid
+  This is fixed: yylval, yynerrs, yychar, and yylloc are now valid
   identifiers for user-provided variables.
 
 *** stdio.h is no longer needed when locations are enabled (yacc.c)
@@ -47,6 +117,8 @@ GNU Bison NEWS
   Changes in Bison 2.7 introduced a dependency on FILE and fprintf when
   locations are enabled.  This is fixed.
 
+*** Warnings about useless %pure-parser/%define api.pure are restored
+
 ** Diagnostics reported by Bison
 
   Most of these features were contributed by Théophile Ranquet and Victor
@@ -58,6 +130,29 @@ GNU Bison NEWS
   activated by default.  The old format can still be used by invoking Bison
   with -fno-caret (or -fnone).
 
+  Some error messages that reproduced excerpts of the grammar are now using
+  the caret information only.  For instance on:
+
+    %%
+    exp: 'a' | 'a';
+
+  Bison 2.7 reports:
+
+    in.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+    in.y:2.12-14: warning: rule useless in parser due to conflicts: exp: 'a' [-Wother]
+
+  Now bison reports:
+
+    in.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+    in.y:2.12-14: warning: rule useless in parser due to conflicts [-Wother]
+     exp: 'a' | 'a';
+                ^^^
+
+  and "bison -fno-caret" reports:
+
+    in.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+    in.y:2.12-14: warning: rule useless in parser due to conflicts [-Wother]
+
 *** Enhancements of the -Werror option
 
   The -Werror=CATEGORY option is now recognized, and will treat specified
@@ -198,12 +293,10 @@ GNU Bison NEWS
     bar.y: error: shift/reduce conflicts: 1 found, 0 expected
     bar.y: error: reduce/reduce conflicts: 2 found, 0 expected
 
-*** Useless precedence
+** Incompatibilities with POSIX Yacc
 
-  Bison now warns about symbols with a declared precedence but no declared
-  associativity (i.e. declared with %precedence), and whose precedence is
-  never used.  In that case, the symbol can be safely declared with %token
-  instead, without modifying the parsing tables.
+  The 'yacc' category is no longer part of '-Wall', enable it explicitly
+  with '-Wyacc'.
 
 ** Additional yylex/yyparse arguments
 
@@ -220,13 +313,271 @@ GNU Bison NEWS
 
     %param {arg1_type *arg1} {arg2_type *arg2}
 
-** Java skeleton improvements
+** Types of values for %define variables
 
-  Contributed by Paolo Bonzini.
+  Bison used to make no difference between '%define foo bar' and '%define
+  foo "bar"'.  The former is now called a 'keyword value', and the latter a
+  'string value'.  A third kind was added: 'code values', such as '%define
+  foo {bar}'.
+
+  Keyword variables are used for fixed value sets, e.g.,
+
+    %define lr.type lalr
+
+  Code variables are used for value in the target language, e.g.,
+
+    %define api.value.type {struct semantic_type}
+
+  String variables are used remaining cases, e.g. file names.
+
+** Variable api.token.prefix
+
+  The variable api.token.prefix changes the way tokens are identified in
+  the generated files.  This is especially useful to avoid collisions
+  with identifiers in the target language.  For instance
+
+    %token FILE for ERROR
+    %define api.token.prefix {TOK_}
+    %%
+    start: FILE for ERROR;
+
+  will generate the definition of the symbols TOK_FILE, TOK_for, and
+  TOK_ERROR in the generated sources.  In particular, the scanner must
+  use these prefixed token names, although the grammar itself still
+  uses the short names (as in the sample rule given above).
+
+** Variable api.value.type
+
+  This new %define variable supersedes the #define macro YYSTYPE.  The use
+  of YYSTYPE is discouraged.  In particular, #defining YYSTYPE *and* either
+  using %union or %defining api.value.type results in undefined behavior.
+
+  Either define api.value.type, or use "%union":
+
+    %union
+    {
+      int ival;
+      char *sval;
+    }
+    %token <ival> INT "integer"
+    %token <sval> STRING "string"
+    %printer { fprintf (yyo, "%d", $$); } <ival>
+    %destructor { free ($$); } <sval>
+
+    /* In yylex().  */
+    yylval.ival = 42; return INT;
+    yylval.sval = "42"; return STRING;
+
+  The %define variable api.value.type supports both keyword and code values.
+
+  The keyword value 'union' means that the user provides genuine types, not
+  union member names such as "ival" and "sval" above (WARNING: will fail if
+  -y/--yacc/%yacc is enabled).
+
+    %define api.value.type union
+    %token <int> INT "integer"
+    %token <char *> STRING "string"
+    %printer { fprintf (yyo, "%d", $$); } <int>
+    %destructor { free ($$); } <char *>
+
+    /* In yylex().  */
+    yylval.INT = 42; return INT;
+    yylval.STRING = "42"; return STRING;
+
+  The keyword value variant is somewhat equivalent, but for C++ special
+  provision is made to allow classes to be used (more about this below).
+
+    %define api.value.type variant
+    %token <int> INT "integer"
+    %token <std::string> STRING "string"
+
+  Code values (in braces) denote user defined types.  This is where YYSTYPE
+  used to be used.
+
+    %code requires
+    {
+      struct my_value
+      {
+        enum
+        {
+          is_int, is_string
+        } kind;
+        union
+        {
+          int ival;
+          char *sval;
+        } u;
+      };
+    }
+    %define api.value.type {struct my_value}
+    %token <u.ival> INT "integer"
+    %token <u.sval> STRING "string"
+    %printer { fprintf (yyo, "%d", $$); } <u.ival>
+    %destructor { free ($$); } <u.sval>
+
+    /* In yylex().  */
+    yylval.u.ival = 42; return INT;
+    yylval.u.sval = "42"; return STRING;
+
+** Variable parse.error
+
+  This variable controls the verbosity of error messages.  The use of the
+  %error-verbose directive is deprecated in favor of "%define parse.error
+  verbose".
+
+** Renamed %define variables
+
+  The following variables have been renamed for consistency.  Backward
+  compatibility is ensured, but upgrading is recommended.
+
+    lr.default-reductions      -> lr.default-reduction
+    lr.keep-unreachable-states -> lr.keep-unreachable-state
+    namespace                  -> api.namespace
+    stype                      -> api.value.type
+
+** Semantic predicates
+
+  Contributed by Paul Hilfinger.
+
+  The new, experimental, semantic-predicate feature allows actions of the
+  form "%?{ BOOLEAN-EXPRESSION }", which cause syntax errors (as for
+  YYERROR) if the expression evaluates to 0, and are evaluated immediately
+  in GLR parsers, rather than being deferred.  The result is that they allow
+  the programmer to prune possible parses based on the values of run-time
+  expressions.
+
+** The directive %expect-rr is now an error in non GLR mode
+
+  It used to be an error only if used in non GLR mode, _and_ if there are
+  reduce/reduce conflicts.
+
+** Tokens are numbered in their order of appearance
+
+  Contributed by Valentin Tolmer.
+
+  With '%token A B', A had a number less than the one of B.  However,
+  precedence declarations used to generate a reversed order.  This is now
+  fixed, and introducing tokens with any of %token, %left, %right,
+  %precedence, or %nonassoc yields the same result.
+
+  When mixing declarations of tokens with a litteral character (e.g., 'a')
+  or with an identifier (e.g., B) in a precedence declaration, Bison
+  numbered the litteral characters first.  For example
+
+    %right A B 'c' 'd'
+
+  would lead to the tokens declared in this order: 'c' 'd' A B.  Again, the
+  input order is now preserved.
+
+  These changes were made so that one can remove useless precedence and
+  associativity declarations (i.e., map %nonassoc, %left or %right to
+  %precedence, or to %token) and get exactly the same output.
+
+** Useless precedence and associativity
+
+  Contributed by Valentin Tolmer.
+
+  When developing and maintaining a grammar, useless associativity and
+  precedence directives are common.  They can be a nuisance: new ambiguities
+  arising are sometimes masked because their conflicts are resolved due to
+  the extra precedence or associativity information.  Furthermore, it can
+  hinder the comprehension of a new grammar: one will wonder about the role
+  of a precedence, where in fact it is useless.  The following changes aim
+  at detecting and reporting these extra directives.
+
+*** Precedence warning category
+
+  A new category of warning, -Wprecedence, was introduced. It flags the
+  useless precedence and associativity directives.
+
+*** Useless associativity
+
+  Bison now warns about symbols with a declared associativity that is never
+  used to resolve conflicts.  In that case, using %precedence is sufficient;
+  the parsing tables will remain unchanged.  Solving these warnings may raise
+  useless precedence warnings, as the symbols no longer have associativity.
+  For example:
+
+    %left '+'
+    %left '*'
+    %%
+    exp:
+      "number"
+    | exp '+' "number"
+    | exp '*' exp
+    ;
+
+  will produce a
+
+    warning: useless associativity for '+', use %precedence [-Wprecedence]
+     %left '+'
+           ^^^
+
+*** Useless precedence
+
+  Bison now warns about symbols with a declared precedence and no declared
+  associativity (i.e., declared with %precedence), and whose precedence is
+  never used.  In that case, the symbol can be safely declared with %token
+  instead, without modifying the parsing tables.  For example:
+
+    %precedence '='
+    %%
+    exp: "var" '=' "number";
+
+  will produce a
+
+    warning: useless precedence for '=' [-Wprecedence]
+     %precedence '='
+                 ^^^
+
+*** Useless precedence and associativity
+
+  In case of both useless precedence and associativity, the issue is flagged
+  as follows:
+
+    %nonassoc '='
+    %%
+    exp: "var" '=' "number";
+
+  The warning is:
+
+    warning: useless precedence and associativity for '=' [-Wprecedence]
+     %nonassoc '='
+               ^^^
+
+** Empty rules
+
+  With help from Joel E. Denny and Gabriel Rassoul.
+
+  Empty rules (i.e., with an empty right-hand side) can now be explicitly
+  marked by the new %empty directive.  Using %empty on a non-empty rule is
+  an error.  The new -Wempty-rule warning reports empty rules without
+  %empty.  On the following grammar:
+
+    %%
+    s: a b c;
+    a: ;
+    b: %empty;
+    c: 'a' %empty;
+
+  bison reports:
+
+    3.4-5: warning: empty rule without %empty [-Wempty-rule]
+     a: {}
+        ^^
+    5.8-13: error: %empty on non-empty rule
+     c: 'a' %empty {};
+            ^^^^^^
+
+** Java skeleton improvements
 
   The constants for token names were moved to the Lexer interface.  Also, it
   is possible to add code to the parser's constructors using "%code init"
   and "%define init_throws".
+  Contributed by Paolo Bonzini.
+
+  The Java skeleton now supports push parsing.
+  Contributed by Dennis Heimbigner.
 
 ** C++ skeletons improvements
 
@@ -249,59 +600,66 @@ GNU Bison NEWS
   used by the scanner, or rejecting invalid combinations from a
   factory invoked by the user actions).
 
-** Renamed %define variables
+*** %define api.value.type variant
 
-  The following variables have been renamed for consistency.  Backward
-  compatibility is ensured, but upgrading is recommended.
+  This is based on a submission from Michiel De Wilde.  With help
+  from Théophile Ranquet.
 
-    lr.default-reductions      -> lr.default-reduction
-    lr.keep-unreachable-states -> lr.keep-unreachable-state
-    namespace                  -> api.namespace
-    stype                      -> api.value.type
+  In this mode, complex C++ objects can be used as semantic values.  For
+  instance:
 
-** Variable api.token.prefix
-
-  The variable api.token.prefix changes the way tokens are identified in
-  the generated files.  This is especially useful to avoid collisions
-  with identifiers in the target language.  For instance
-
-    %token FILE for ERROR
-    %define api.token.prefix "TOK_"
+    %token <::std::string> TEXT;
+    %token <int> NUMBER;
+    %token SEMICOLON ";"
+    %type <::std::string> item;
+    %type <::std::list<std::string>> list;
     %%
-    start: FILE for ERROR;
+    result:
+      list  { std::cout << $1 << std::endl; }
+    ;
 
-  will generate the definition of the symbols TOK_FILE, TOK_for, and
-  TOK_ERROR in the generated sources.  In particular, the scanner must
-  use these prefixed token names, although the grammar itself still
-  uses the short names (as in the sample rule given above).
+    list:
+      %empty        { /* Generates an empty string list. */ }
+    | list item ";" { std::swap ($$, $1); $$.push_back ($2); }
+    ;
 
-** Variable parse.error
+    item:
+      TEXT    { std::swap ($$, $1); }
+    | NUMBER  { $$ = string_cast ($1); }
+    ;
 
-  This variable controls the verbosity of error messages.  The use of the
-  %error-verbose directive is deprecated in favor of "%define parse.error
-  verbose".
+*** %define api.token.constructor
 
-** Semantic predicates
+  When variants are enabled, Bison can generate functions to build the
+  tokens.  This guarantees that the token type (e.g., NUMBER) is consistent
+  with the semantic value (e.g., int):
 
-  Contributed by Paul Hilfinger.
+    parser::symbol_type yylex ()
+    {
+      parser::location_type loc = ...;
+      ...
+      return parser::make_TEXT ("Hello, world!", loc);
+      ...
+      return parser::make_NUMBER (42, loc);
+      ...
+      return parser::make_SEMICOLON (loc);
+      ...
+    }
 
-  The new, experimental, semantic-predicate feature allows actions of the
-  form "%?{ BOOLEAN-EXPRESSION }", which cause syntax errors (as for
-  YYERROR) if the expression evaluates to 0, and are evaluated immediately
-  in GLR parsers, rather than being deferred.  The result is that they allow
-  the programmer to prune possible parses based on the values of run-time
-  expressions.
+*** C++ locations
 
-** The directive %expect-rr is now an error in non GLR mode
+  There are operator- and operator-= for 'location'.  Negative line/column
+  increments can no longer underflow the resulting value.
 
-  It used to be an error only if used in non GLR mode, _and_ if there are
-  reduce/reduce conflicts.
+* Noteworthy changes in release 2.7.1 (2013-04-15) [stable]
 
-** Token numbering has changed to preserve the user-defined order
+** Bug fixes
 
-  When declaring %token A B, the numbering for A is inferior to B. Up to now,
-  when declaring associativity at the same time, with %left (or %right,
-  %precedence, %nonassoc), B was inferior to A.
+*** Fix compiler attribute portability (yacc.c)
+
+  With locations enabled, __attribute__ was used unprotected.
+
+*** Fix some compiler warnings (lalr1.cc)
 
 * Noteworthy changes in release 2.7 (2012-12-12) [stable]
 
@@ -353,8 +711,8 @@ GNU Bison NEWS
      exp: exp '+' exp { $exp = $1 + $3; };
                   ^^^
 
-  The default behaviour for now is still not to display these unless
-  explictly asked with -fcaret (or -fall). However, in a later release, it
+  The default behavior for now is still not to display these unless
+  explicitly asked with -fcaret (or -fall). However, in a later release, it
   will be made the default behavior (but may still be deactivated with
   -fno-caret).
 
@@ -441,7 +799,7 @@ GNU Bison NEWS
 
   Other issues in the test suite have been addressed.
 
-  Nul characters are correctly displayed in error messages.
+  Null characters are correctly displayed in error messages.
 
   When possible, yylloc is correctly initialized before calling yylex.  It
   is no longer necessary to initialize it in the %initial-action.
@@ -2357,7 +2715,12 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
  LocalWords:  Automake TMPDIR LESSEQ ylwrap endif yydebug YYTOKEN YYLSP ival hh
  LocalWords:  extern YYTOKENTYPE TOKENTYPE yytokentype tokentype STYPE lval pdf
  LocalWords:  lang yyoutput dvi html ps POSIX lvalp llocp Wother nterm arg init
- LocalWords:  TOK calc yyo fval Wconflicts
+ LocalWords:  TOK calc yyo fval Wconflicts parsers yystackp yyval yynerrs
+ LocalWords:  Théophile Ranquet Santet fno fnone stype associativity Tolmer
+ LocalWords:  Wprecedence Rassoul Wempty Paolo Bonzini parser's Michiel loc
+ LocalWords:  redeclaration sval fcaret reentrant XSLT xsl Wmaybe yyvsp Tedi
+ LocalWords:  pragmas noreturn untyped Rozenman unexpanded Wojciech Polak
+ LocalWords:  Alexandre MERCHANTABILITY yytype
 
 Local Variables:
 mode: outline

README

@@ -30,7 +30,7 @@ not answer them, please send mail to <[email protected]>.
 
 * Bug reports
 Please send bug reports to <[email protected]>.  Please include the
-version number from `bison --version', and a complete, self-contained
+version number from 'bison --version', and a complete, self-contained
 test case in each bug report.
 
 * Copyright statements

README-hacking

@@ -62,13 +62,22 @@ tools we depend upon, including:
 - Gettext <http://www.gnu.org/software/gettext/>
 - Graphviz <http://www.graphviz.org>
 - Gzip <http://www.gnu.org/software/gzip/>
+- Help2man <http://www.gnu.org/software/help2man/>
 - Perl <http://www.cpan.org/>
 - Rsync <http://samba.anu.edu.au/rsync/>
 - Tar <http://www.gnu.org/software/tar/>
+- Texinfo <http://www.gnu.org/software/texinfo/>
 
 Valgrind <http://valgrind.org/> is also highly recommended, if it supports
 your architecture.
 
+If you're using a GNU/Linux distribution, the easiest way to install the
+above packages depends on your system.  The following shell command should
+work for Debian-based systems such as Ubuntu:
+
+  sudo apt-get install \
+    autoconf automake autopoint flex graphviz help2man texinfo valgrind
+
 Bison is written using Bison grammars, so there are bootstrapping issues.
 The bootstrap script attempts to discover when the C code generated from the
 grammars is out of date, and to bootstrap with an out-of-date version of the

REFERENCES

@@ -9,7 +9,7 @@ Bison supports the @N construction, which gives you access to
 the starting and ending line number and character number associated
 with any of the symbols in the current rule.
 
-Also, Bison supports the command `%expect N' which says not to mention
+Also, Bison supports the command '%expect N' which says not to mention
 the conflicts if there are N shift/reduce conflicts and no reduce/reduce
 conflicts.
 

THANKS

@@ -25,10 +25,13 @@ Bruce Lilly               [email protected]
 Bruno Haible              [email protected]
 Charles-Henri de Boysson  [email protected]
 Christian Burger          [email protected]
+Colin Daley               [email protected]
 Cris Bailiff              [email protected]
 Cris van Pelt             [email protected]
 Csaba Raduly              [email protected]
 Dagobert Michelsen        [email protected]
+Daniel Frużyński          [email protected]
+Daniel Galloway           [email protected]
 Daniel Hagerty            [email protected]
 David J. MacKenzie        [email protected]
 David Kastrup             [email protected]
@@ -37,6 +40,7 @@ Derek M. Jones            [email protected]
 Di-an Jan                 [email protected]
 Dick Streefland           [email protected]
 Didier Godefroy           [email protected]
+Efi Fogel                 [email protected]
 Enrico Scholz             [email protected]
 Eric Blake                [email protected]
 Evgeny Stambulchik        [email protected]
@@ -44,6 +48,7 @@ Fabrice Bauzac            [email protected]
 Florian Krohm             [email protected]
 Frank Heckenbach          [email protected]
 Frans Englich             [email protected]
+Gabriel Rassoul           [email protected]
 Georg Sauthoff            [email protected]
 George Neuner             [email protected]
 Gilles Espinasse          [email protected]
@@ -61,6 +66,7 @@ Johan van Selst           [email protected]
 Jonathan Fabrizio         [email protected]
 Jonathan Nieder           [email protected]
 Juan Manuel Guerrero      [email protected]
+Ken Moffat                [email protected]
 Kees Zeelenberg           [email protected]
 Keith Browne              [email protected]
 Laurent Mascherpa         [email protected]
@@ -74,6 +80,7 @@ Martin Mokrejs            [email protected]
 Martin Nylin              [email protected]
 Matt Kraai                [email protected]
 Matt Rosing               [email protected]
+Michael Felt              [email protected]
 Michael Hayes             [email protected]
 Michael Raskin            [email protected]
 Michiel De Wilde          [email protected]
@@ -89,6 +96,7 @@ Odd Arild Olsen           [email protected]
 Oleg Smolsky              [email protected]
 Oleksii Taran             [email protected]
 Paolo Bonzini             [email protected]
+Paolo Simone Gasparello   [email protected]
 Pascal Bart               [email protected]
 Paul Eggert               [email protected]
 Paul Hilfinger            [email protected]
@@ -97,6 +105,7 @@ Peter Eisentraut          [email protected]
 Peter Fales               [email protected]
 Peter Hamorsky            [email protected]
 Peter Simons              [email protected]
+Petr Machata              [email protected]
 Piotr Gackiewicz          [email protected]
 Quentin Hocquet           [email protected]
 Quoc Peyrot               [email protected]
@@ -104,8 +113,10 @@ R Blake                   [email protected]
 Raja R Harinath           [email protected]
 Ralf Wildenhues           [email protected]
 Richard Stallman          [email protected]
+Rici Lake                 [email protected]
 Rob Vermaas               [email protected]
 Robert Anisko             [email protected]
+Rob Conde                 [email protected]
 Roland Levillain          [email protected]
 Satya Kiran Popuri        [email protected]
 Sebastian Setzer          [email protected]
@@ -126,6 +137,7 @@ Tommy Nordgren            [email protected]
 Troy A. Johnson           [email protected]
 Tys Lefering              [email protected]
 Valentin Tolmer           [email protected]
+Victor Khomenko           [email protected]
 Vin Shelton               [email protected]
 W.C.A. Wijngaards         [email protected]
 Wayne Green               [email protected]

TODO

@@ -1,16 +1,27 @@
 * Short term
 ** Graphviz display code thoughts
 The code for the --graph option is over two files: print_graph, and
-graphviz. I believe this is because Bison used to also produce VCG graphs,
-but since this is no longer true, maybe we could consider these files for
-fusion.
+graphviz. This is because Bison used to also produce VCG graphs, but since
+this is no longer true, maybe we could consider these files for fusion.
 
-Little effort factoring seems to have been given to factoring in these files,
-and their print-xml and print counterpart. We would very much like to re-use
-the pretty format of states from .output in the .dot
+An other consideration worth noting is that print_graph.c (correct me if I
+am wrong) should contain generic functions, whereas graphviz.c and other
+potential files should contain just the specific code for that output
+format. It will probably prove difficult to tell if the implementation is
+actually generic whilst only having support for a single format, but it
+would be nice to keep stuff a bit tidier: right now, the construction of the
+bitset used to show reductions is in the graphviz-specific code, and on the
+opposite side we have some use of \l, which is graphviz-specific, in what
+should be generic code.
 
-Also, the underscore in print_graph.[ch] isn't very fitting considering
-the dashes in the other filenames.
+Little effort seems to have been given to factoring these files and their
+rint{,-xml} counterpart. We would very much like to re-use the pretty format
+of states from .output for the graphs, etc.
+
+Also, the underscore in print_graph.[ch] isn't very fitting considering the
+dashes in the other filenames.
+
+Since graphviz dies on medium-to-big grammars, maybe consider an other tool?
 
 ** push-parser
 Check it too when checking the different kinds of parsers.  And be
@@ -165,13 +176,13 @@ part of $default.  Should we make the two reductions explicit, or just
 keep $default?  See the following point.
 
 ** Disabled Reductions
-See `tests/conflicts.at (Defaulted Conflicted Reduction)', and decide
+See 'tests/conflicts.at (Defaulted Conflicted Reduction)', and decide
 what we want to do.
 
 ** Documentation
 Extend with error productions.  The hard part will probably be finding
 the right rule so that a single state does not exhibit too many yet
-undocumented ``features''.  Maybe an empty action ought to be
+undocumented ''features''.  Maybe an empty action ought to be
 presented too.  Shall we try to make a single grammar with all these
 features, or should we have several very small grammars?
 
@@ -232,9 +243,9 @@ into
         exp: exp '+' exp | exp '&' exp;
 
 when there are no actions.  This can significantly speed up some
-grammars.  I can't find the papers.  In particular the book `LR
+grammars.  I can't find the papers.  In particular the book 'LR
 parsing: Theory and Practice' is impossible to find, but according to
-`Parsing Techniques: a Practical Guide', it includes information about
+'Parsing Techniques: a Practical Guide', it includes information about
 this issue.  Does anybody have it?
 
 

bootstrap

@@ -1,6 +1,6 @@
 #! /bin/sh
 # Print a version string.
-scriptversion=2012-12-28.10; # UTC
+scriptversion=2013-08-15.22; # UTC
 
 # Bootstrap this package from checked-out sources.
 
@@ -140,20 +140,21 @@ po_download_command_format2=\
 "wget --mirror -nd -q -np -A.po -P '%s' \
  http://translationproject.org/latest/%s/"
 
+# Prefer a non-empty tarname (4th argument of AC_INIT if given), else
+# fall back to the package name (1st argument with munging)
 extract_package_name='
-  /^AC_INIT(/{
-     /.*,.*,.*, */{
-       s///
-       s/[][]//g
-       s/)$//
+  /^AC_INIT(\[*/{
+     s///
+     /^[^,]*,[^,]*,[^,]*,[ []*\([^][ ,)]\)/{
+       s//\1/
+       s/[],)].*//
        p
        q
      }
-     s/AC_INIT(\[*//
-     s/]*,.*//
+     s/[],)].*//
      s/^GNU //
      y/ABCDEFGHIJKLMNOPQRSTUVWXYZ/abcdefghijklmnopqrstuvwxyz/
-     s/[^A-Za-z0-9_]/-/g
+     s/[^abcdefghijklmnopqrstuvwxyz0123456789_]/-/g
      p
   }
 '
@@ -208,12 +209,16 @@ bootstrap_sync=false
 # Use git to update gnulib sources
 use_git=true
 
+check_exists() {
+  ($1 --version </dev/null) >/dev/null 2>&1
+  test $? -lt 126
+}
+
 # find_tool ENVVAR NAMES...
 # -------------------------
 # Search for a required program.  Use the value of ENVVAR, if set,
-# otherwise find the first of the NAMES that can be run (i.e.,
-# supports --version).  If found, set ENVVAR to the program name,
-# die otherwise.
+# otherwise find the first of the NAMES that can be run.
+# If found, set ENVVAR to the program name, die otherwise.
 #
 # FIXME: code duplication, see also gnu-web-doc-update.
 find_tool ()
@@ -223,27 +228,21 @@ find_tool ()
   find_tool_names=$@
   eval "find_tool_res=\$$find_tool_envvar"
   if test x"$find_tool_res" = x; then
-    for i
-    do
-      if ($i --version </dev/null) >/dev/null 2>&1; then
-       find_tool_res=$i
-       break
+    for i; do
+      if check_exists $i; then
+        find_tool_res=$i
+        break
       fi
     done
-  else
-    find_tool_error_prefix="\$$find_tool_envvar: "
   fi
-  test x"$find_tool_res" != x \
-    || die "one of these is required: $find_tool_names"
-  ($find_tool_res --version </dev/null) >/dev/null 2>&1 \
-    || die "${find_tool_error_prefix}cannot run $find_tool_res --version"
+  if test x"$find_tool_res" = x; then
+    warn_ "one of these is required: $find_tool_names;"
+    die   "alternatively set $find_tool_envvar to a compatible tool"
+  fi
   eval "$find_tool_envvar=\$find_tool_res"
   eval "export $find_tool_envvar"
 }
 
-# Find sha1sum, named gsha1sum on MacPorts, and shasum on Mac OS X 10.6.
-find_tool SHA1SUM sha1sum gsha1sum shasum
-
 # Override the default configuration, if necessary.
 # Make sure that bootstrap.conf is sourced from the current directory
 # if we were invoked as "sh bootstrap".
@@ -255,12 +254,12 @@ esac
 # Extra files from gnulib, which override files from other sources.
 test -z "${gnulib_extra_files}" && \
   gnulib_extra_files="
-        $build_aux/install-sh
-        $build_aux/mdate-sh
-        $build_aux/texinfo.tex
-        $build_aux/depcomp
-        $build_aux/config.guess
-        $build_aux/config.sub
+        build-aux/install-sh
+        build-aux/mdate-sh
+        build-aux/texinfo.tex
+        build-aux/depcomp
+        build-aux/config.guess
+        build-aux/config.sub
         doc/INSTALL
 "
 
@@ -306,34 +305,34 @@ if test -n "$checkout_only_file" && test ! -r "$checkout_only_file"; then
   die "Bootstrapping from a non-checked-out distribution is risky."
 fi
 
-# Ensure that lines starting with ! sort last, per gitignore conventions
-# for whitelisting exceptions after a more generic blacklist pattern.
-sort_patterns() {
-  sort -u "$@" | sed '/^!/ {
-    H
-    d
-  }
-  $ {
-    P
-    x
-    s/^\n//
-  }' | sed '/^$/d'
+# Strip blank and comment lines to leave significant entries.
+gitignore_entries() {
+  sed '/^#/d; /^$/d' "$@"
 }
 
-# If $STR is not already on a line by itself in $FILE, insert it,
-# sorting the new contents of the file and replacing $FILE with the result.
-insert_sorted_if_absent() {
+# If $STR is not already on a line by itself in $FILE, insert it at the start.
+# Entries are inserted at the start of the ignore list to ensure existing
+# entries starting with ! are not overridden.  Such entries support
+# whitelisting exceptions after a more generic blacklist pattern.
+insert_if_absent() {
   file=$1
   str=$2
   test -f $file || touch $file
-  echo "$str" | sort_patterns - $file | cmp -s - $file > /dev/null \
-    || { echo "$str" | sort_patterns - $file > $file.bak \
-      && mv $file.bak $file; } \
-    || die "insert_sorted_if_absent $file $str: failed"
+  test -r $file || die "Error: failed to read ignore file: $file"
+  duplicate_entries=$(gitignore_entries $file | sort | uniq -d)
+  if [ "$duplicate_entries" ] ; then
+    die "Error: Duplicate entries in $file: " $duplicate_entries
+  fi
+  linesold=$(gitignore_entries $file | wc -l)
+  linesnew=$( { echo "$str"; cat $file; } | gitignore_entries | sort -u | wc -l)
+  if [ $linesold != $linesnew ] ; then
+    { echo "$str" | cat - $file > $file.bak && mv $file.bak $file; } \
+      || die "insert_if_absent $file $str: failed"
+  fi
 }
 
 # Adjust $PATTERN for $VC_IGNORE_FILE and insert it with
-# insert_sorted_if_absent.
+# insert_if_absent.
 insert_vc_ignore() {
   vc_ignore_file="$1"
   pattern="$2"
@@ -344,7 +343,7 @@ insert_vc_ignore() {
     # .gitignore entry.
     pattern=$(echo "$pattern" | sed s,^,/,);;
   esac
-  insert_sorted_if_absent "$vc_ignore_file" "$pattern"
+  insert_if_absent "$vc_ignore_file" "$pattern"
 }
 
 # Die if there is no AC_CONFIG_AUX_DIR($build_aux) line in configure.ac.
@@ -468,8 +467,7 @@ check_versions() {
     if [ "$req_ver" = "-" ]; then
       # Merely require app to exist; not all prereq apps are well-behaved
       # so we have to rely on $? rather than get_version.
-      $app --version >/dev/null 2>&1
-      if [ 126 -le $? ]; then
+      if ! check_exists $app; then
         warn_ "Error: '$app' not found"
         ret=1
       fi
@@ -502,6 +500,12 @@ print_versions() {
   # can't depend on column -t
 }
 
+# Find sha1sum, named gsha1sum on MacPorts, shasum on Mac OS X 10.6.
+# Also find the compatible sha1 utility on the BSDs
+if test x"$SKIP_PO" = x; then
+  find_tool SHA1SUM sha1sum gsha1sum shasum sha1
+fi
+
 use_libtool=0
 # We'd like to use grep -E, to see if any of LT_INIT,
 # AC_PROG_LIBTOOL, AM_PROG_LIBTOOL is used in configure.ac,
@@ -550,10 +554,10 @@ fi
 echo "$0: Bootstrapping from checked-out $package sources..."
 
 # See if we can use gnulib's git-merge-changelog merge driver.
-if test -d .git && (git --version) >/dev/null 2>/dev/null ; then
+if $use_git && test -d .git && check_exists git; then
   if git config merge.merge-changelog.driver >/dev/null ; then
     :
-  elif (git-merge-changelog --version) >/dev/null 2>/dev/null ; then
+  elif check_exists git-merge-changelog; then
     echo "$0: initializing git-merge-changelog driver"
     git config merge.merge-changelog.name 'GNU-style ChangeLog merge driver'
     git config merge.merge-changelog.driver 'git-merge-changelog %O %A %B'
@@ -573,13 +577,17 @@ git_modules_config () {
   test -f .gitmodules && git config --file .gitmodules "$@"
 }
 
-gnulib_path=$(git_modules_config submodule.gnulib.path)
-test -z "$gnulib_path" && gnulib_path=gnulib
+if $use_git; then
+  gnulib_path=$(git_modules_config submodule.gnulib.path)
+  test -z "$gnulib_path" && gnulib_path=gnulib
+fi
 
-# Get gnulib files.
+# Get gnulib files.  Populate $GNULIB_SRCDIR, possibly updating a
+# submodule, for use in the rest of the script.
 
 case ${GNULIB_SRCDIR--} in
 -)
+  # Note that $use_git is necessarily true in this case.
   if git_modules_config submodule.gnulib.url >/dev/null; then
     echo "$0: getting gnulib files..."
     git submodule init || exit $?
@@ -600,8 +608,8 @@ case ${GNULIB_SRCDIR--} in
   GNULIB_SRCDIR=$gnulib_path
   ;;
 *)
-  # Use GNULIB_SRCDIR as a reference.
-  if test -d "$GNULIB_SRCDIR"/.git && \
+  # Use GNULIB_SRCDIR directly or as a reference.
+  if $use_git && test -d "$GNULIB_SRCDIR"/.git && \
         git_modules_config submodule.gnulib.url >/dev/null; then
     echo "$0: getting gnulib files..."
     if git submodule -h|grep -- --reference > /dev/null; then
@@ -627,12 +635,19 @@ case ${GNULIB_SRCDIR--} in
   ;;
 esac
 
+# $GNULIB_SRCDIR now points to the version of gnulib to use, and
+# we no longer need to use git or $gnulib_path below here.
+
 if $bootstrap_sync; then
   cmp -s "$0" "$GNULIB_SRCDIR/build-aux/bootstrap" || {
     echo "$0: updating bootstrap and restarting..."
+    case $(sh -c 'echo "$1"' -- a) in
+      a) ignored=--;;
+      *) ignored=ignored;;
+    esac
     exec sh -c \
       'cp "$1" "$2" && shift && exec "${CONFIG_SHELL-/bin/sh}" "$@"' \
-      -- "$GNULIB_SRCDIR/build-aux/bootstrap" \
+      $ignored "$GNULIB_SRCDIR/build-aux/bootstrap" \
       "$0" "$@" --no-bootstrap-sync
   }
 fi
@@ -680,11 +695,10 @@ update_po_files() {
     cksum_file="$ref_po_dir/$po.s1"
     if ! test -f "$cksum_file" ||
         ! test -f "$po_dir/$po.po" ||
-        ! $SHA1SUM -c --status "$cksum_file" \
-            < "$new_po" > /dev/null; then
+        ! $SHA1SUM -c "$cksum_file" < "$new_po" > /dev/null 2>&1; then
       echo "$me: updated $po_dir/$po.po..."
       cp "$new_po" "$po_dir/$po.po" \
-          && $SHA1SUM < "$new_po" > "$cksum_file"
+          && $SHA1SUM < "$new_po" > "$cksum_file" || return
     fi
   done
 }

bootstrap.conf

@@ -34,7 +34,8 @@ gnulib_modules='
   readme-release
   realloc-posix
   spawn-pipe stdbool stpcpy strdup-posix strerror strtoul strverscmp
-  unistd unistd-safer unlocked-io update-copyright unsetenv verify
+  unistd unistd-safer unlink unlocked-io
+  update-copyright unsetenv verify
   warnings
   xalloc
   xalloc-die

build-aux/linux-gnu.valgrind

@@ -0,0 +1,16 @@
+# Linux seattle 2.6.32-5-amd64 #1 SMP Thu Mar 22 17:26:33 UTC 2012
+# x86_64 GNU/Linux
+{
+   index
+   Memcheck:Cond
+   fun:index
+   fun:expand_dynamic_string_token
+   fun:_dl_map_object
+   fun:map_doit
+   fun:_dl_catch_error
+   fun:do_preload
+   fun:dl_main
+   fun:_dl_sysdep_start
+   fun:_dl_start
+   obj:/lib/ld-2.11.3.so
+}

build-aux/local.mk

@@ -1,5 +1,3 @@
-## Makefile for Bison testsuite.
-
 # Copyright (C) 2000-2013 Free Software Foundation, Inc.
 #
 # This program is free software: you can redistribute it and/or modify
@@ -18,6 +16,7 @@
 EXTRA_DIST +=                                   \
   build-aux/cross-options.pl                    \
   build-aux/darwin11.4.0.valgrind               \
+  build-aux/linux-gnu.valgrind                  \
   build-aux/move-if-change                      \
   build-aux/prev-version.txt                    \
   build-aux/update-b4-copyright

cfg.mk

@@ -135,7 +135,7 @@ _sed_rm_comments_q = $(subst ','\'',$(_sed_remove_comments))
 
 _space_before_paren_exempt =? \\n\\$$
 _space_before_paren_exempt = \
-  (^ *\#|\\n\\$$|%s\(to %s|(date|group|character)\(s\))
+  (^ *\#|(LA)?LR\([01]\)|percent_(code|define)|b4_syncline|m4_(define|init)|symbol)
 # Ensure that there is a space before each open parenthesis in C code.
 sc_space_before_open_paren:
 	@if $(VC_LIST_EXCEPT) | grep -l '\.[ch]$$' > /dev/null; then	\
@@ -175,5 +175,6 @@ $(call exclude,								\
   prohibit_strcmp=^doc/bison\.texi|tests/local\.at$$			\
   prohibit_tab_based_indentation=\.(am|mk)$$|^djgpp/|^\.git		\
   require_config_h_first=^(lib/yyerror|data/(glr|yacc))\.c$$		\
+  space_before_open_paren=^(data/|djgpp/)                               \
   unmarked_diagnostics=^(djgpp/|doc/bison.texi$$|tests/c\+\+\.at$$)	\
 )

configure.ac

@@ -18,7 +18,7 @@
 # In order for some versions of Sun Studio to compile our C++ test cases
 # correctly, we need Autoconf 2.64 or better to handle the restrict
 # keyword in at least string.h from gnulib.  We need Autoconf 2.68 or
-# better to avoid a typo in the `configure --help' entry for the YACC
+# better to avoid a typo in the 'configure --help' entry for the YACC
 # environment variable.
 AC_PREREQ([2.68])
 m4_pattern_forbid([^gl_[A-Z]])
@@ -33,11 +33,7 @@ AC_DEFINE_UNQUOTED([PACKAGE_COPYRIGHT_YEAR], [$PACKAGE_COPYRIGHT_YEAR],
 AC_CONFIG_AUX_DIR([build-aux])
 AC_CONFIG_MACRO_DIR([m4])
 
-# Automake 1.10.3 and 1.11.1 fix a security flaw discussed here:
-#
-#   http://thread.gmane.org/gmane.comp.sysutils.autotools.announce/131
-#
-# To avoid 1.11, we make 1.11.1 the minimum version.
+# We use Automake 1.14's %D% and %C%.
 #
 # We want gnits strictness only when rolling a stable release.  For
 # release candidates, we use version strings like 2.4.3_rc1, but gnits
@@ -45,7 +41,7 @@ AC_CONFIG_MACRO_DIR([m4])
 # releases, we want to be able run make dist without being required to
 # add a bogus NEWS entry.  In that case, the version string
 # automatically contains a dash, which we also let disable gnits.
-AM_INIT_AUTOMAKE([1.11.1 dist-xz nostdinc
+AM_INIT_AUTOMAKE([1.14 dist-xz nostdinc
                  color-tests parallel-tests
                  silent-rules]
                  m4_bmatch(m4_defn([AC_PACKAGE_VERSION]), [[-_]],
@@ -82,7 +78,7 @@ AC_ARG_ENABLE([gcc-warnings],
  esac],
               [enable_gcc_warnings=no])
 if test "$enable_gcc_warnings" = yes; then
-  warn_common='-Wall -Wextra -Wno-sign-compare -Wcast-align
+  warn_common='-Wall-Wextra -Wno-sign-compare -Wcast-align -Wdocumentation
     -Wformat -Wpointer-arith -Wwrite-strings'
   warn_c='-Wbad-function-cast -Wshadow -Wstrict-prototypes'
   warn_cxx='-Wnoexcept'
@@ -91,7 +87,7 @@ if test "$enable_gcc_warnings" = yes; then
   # -fno-color-diagnostics: Clang's use of colors in the error
   # messages is confusing the tests looking at the compiler's output
   # (e.g., synclines.at).
-  warn_tests='-Wundef -pedantic -fno-color-diagnostics'
+  warn_tests='-Wundef -pedantic -Wsign-compare -fno-color-diagnostics'
 
   AC_LANG_PUSH([C])
   # Clang supports many of GCC's -W options, but only issues warnings
@@ -143,9 +139,11 @@ if test "$enable_gcc_warnings" = yes; then
     gl_WARN_ADD([$i], [WARN_CXXFLAGS_TEST])
   done
   # Clang++ 3.2+ reject C code generated by Flex.
-  gl_WARN_ADD([-Wno-null-conversion], [WARN_NO_NULL_CONVERSION_CXXFLAGS])
-  # Variants break strict aliasing analysis.
-  gl_WARN_ADD([-fno-strict-aliasing], [NO_STRICT_ALIAS_CXXFLAGS])
+  gl_WARN_ADD([-Wno-null-conversion], [FLEX_SCANNER_CXXFLAGS])
+  # So does G++ 4.8...
+  gl_WARN_ADD([-Wno-sign-compare], [FLEX_SCANNER_CXXFLAGS])
+  # ... possiby in std=c++11 mode.
+  gl_WARN_ADD([-Wno-zero-as-null-pointer-constant], [FLEX_SCANNER_CXXFLAGS])
   CXXFLAGS=$save_CXXFLAGS
   AC_LANG_POP([C++])
 fi
@@ -159,21 +157,17 @@ AC_ARG_ENABLE([yacc],
   [AC_HELP_STRING([--disable-yacc],
      [do not build a yacc command or an -ly library])],
   , [enable_yacc=yes])
-case $enable_yacc in
-yes)
-  YACC_SCRIPT=src/yacc
-  YACC_LIBRARY=lib/liby.a;;
-*)
-  YACC_SCRIPT=
-  YACC_LIBRARY=;;
-esac
-AC_SUBST([YACC_SCRIPT])
-AC_SUBST([YACC_LIBRARY])
+AM_CONDITIONAL([ENABLE_YACC], [test "$enable_yacc" = yes])
 
 # Checks for programs.
 AM_MISSING_PROG([DOT], [dot])
 AC_PROG_LEX
-$LEX_IS_FLEX || AC_MSG_ERROR([Flex is required])
+$LEX_IS_FLEX || test "X$LEX" = X: || {
+  AC_MSG_WARN([bypassing lex because flex is required])
+  LEX=:
+}
+AM_CONDITIONAL([FLEX_CXX_WORKS],
+  [$LEX_IS_FLEX && test $bison_cv_cxx_works = yes])
 AC_PROG_YACC
 AC_PROG_RANLIB
 AC_PROG_GNU_M4
@@ -228,10 +222,16 @@ case $VALGRIND:$host_os in
   '':*) ;;
   *:darwin*)
     # See README-hacking.
-    # VALGRIND+=' --suppressions=$(abs_top_srcdir)/build-aux/darwin11.4.0.valgrind'
+    # VALGRIND+='-q --suppressions=$(abs_top_srcdir)/build-aux/darwin11.4.0.valgrind'
     VALGRIND=;;
   *:*)
-    AC_SUBST([VALGRIND_PREBISON], ["$VALGRIND -q"]);;
+    suppfile=build-aux/$host_os.valgrind
+    if test -f "$srcdir/$suppfile"; then
+      VALGRIND="$VALGRIND --gen-suppressions=all"
+      VALGRIND="$VALGRIND --suppressions=\$(abs_top_srcdir)/$suppfile"
+    fi
+    AC_SUBST([VALGRIND_PREBISON], ["$VALGRIND -q"])
+    ;;
 esac
 
 AM_MISSING_PROG([AUTOM4TE], [autom4te])

data/README

@@ -27,7 +27,7 @@ Currently, the supported skeletons are:
 These skeletons are the only ones supported by the Bison team.
 Because the interface between skeletons and the bison program is not
 finished, *we are not bound to it*.  In particular, Bison is not
-mature enough for us to consider that ``foreign skeletons'' are
+mature enough for us to consider that "foreign skeletons" are
 supported.
 
 * m4sugar

data/bison.m4

@@ -85,6 +85,20 @@ m4_changecom([#])
 ])
 
 
+# b4_divert_kill(CODE)
+# --------------------
+# Expand CODE for its side effects, discard its output.
+m4_define([b4_divert_kill],
+[m4_divert_text([KILL], [$1])])
+
+
+# b4_define_silent(MACRO, CODE)
+# -----------------------------
+# Same as m4_define, but throw away the expansion of CODE.
+m4_define([b4_define_silent],
+[m4_define([$1], [b4_divert_kill([$2])])])
+
+
 ## ---------------- ##
 ## Error handling.  ##
 ## ---------------- ##
@@ -313,7 +327,7 @@ m4_define([b4_define_flag_if],
 # _b4_define_flag_if($1, $2, FLAG)
 # --------------------------------
 # Work around the impossibility to define macros inside macros,
-# because issuing `[$1]' is not possible in M4.  GNU M4 should provide
+# because issuing '[$1]' is not possible in M4.  GNU M4 should provide
 # $$1 a la M5/TeX.
 m4_define([_b4_define_flag_if],
 [m4_if([$1$2], $[1]$[2], [],
@@ -347,6 +361,7 @@ b4_define_flag_if([yacc])               # Whether POSIX Yacc is emulated.
 #   Whether the symbol has an id.
 # - id: string
 #   If has_id, the id.  Guaranteed to be usable as a C identifier.
+#   Prefixed by api.token.prefix if defined.
 # - tag: string.
 #   A representat of the symbol.  Can be 'foo', 'foo.id', '"foo"' etc.
 # - user_number: integer
@@ -357,9 +372,13 @@ b4_define_flag_if([yacc])               # Whether POSIX Yacc is emulated.
 #   The internalized number (used after yytranslate).
 # - has_type: 0, 1
 #   Whether has a semantic value.
+# - type_tag: string
+#   When api.value.type=union, the generated name for the union member.
+#   yytype_INT etc. for symbols that has_id, otherwise yytype_1 etc.
 # - type
 #   If it has a semantic value, its type tag, or, if variant are used,
 #   its type.
+#   In the case of api.value.type=union, type is the real type (e.g. int).
 # - has_printer: 0, 1
 # - printer: string
 # - printer_file: string
@@ -442,6 +461,24 @@ m4_define([b4_symbol_destructor], [b4_symbol_action([$1], [destructor])])
 m4_define([b4_symbol_printer],    [b4_symbol_action([$1], [printer])])
 
 
+# b4_symbol_actions(KIND, [TYPE = yytype])
+# ----------------------------------------
+# Emit the symbol actions for KIND ("printer" or "destructor").
+# Dispatch on TYPE.
+m4_define([b4_symbol_actions],
+[m4_pushdef([b4_actions_], m4_expand([b4_symbol_foreach([b4_symbol_$1])]))dnl
+m4_ifval(m4_defn([b4_actions_]),
+[switch (m4_default([$2], [yytype]))
+    {
+      m4_defn([b4_actions_])
+      default:
+        break;
+    }dnl
+],
+[YYUSE (m4_default([$2], [yytype]));])dnl
+m4_popdef([b4_actions_])dnl
+])
+
 # b4_symbol_case_(SYMBOL-NUM)
 # ---------------------------
 # Issue a "case NUM" for SYMBOL-NUM.
@@ -577,14 +614,14 @@ m4_define([b4_define_user_code],
 # b4_user_initial_action
 # b4_user_post_prologue
 # b4_user_pre_prologue
-# b4_user_stype
+# b4_user_union_members
 # ----------------------
 # Macros that issue user code, ending with synclines.
 b4_define_user_code([actions])
 b4_define_user_code([initial_action])
 b4_define_user_code([post_prologue])
 b4_define_user_code([pre_prologue])
-b4_define_user_code([stype])
+b4_define_user_code([union_members])
 
 
 # b4_check_user_names(WHAT, USER-LIST, BISON-NAMESPACE)
@@ -665,9 +702,9 @@ m4_define([b4_percent_define_use],
 #   b4_percent_define_get([[foo]])
 m4_define([b4_percent_define_get],
 [b4_percent_define_use([$1])dnl
-m4_ifdef([b4_percent_define(]$1[)],
-         [m4_indir([b4_percent_define(]$1[)])],
-         [$2])])
+b4_percent_define_ifdef_([$1],
+                         [m4_indir([b4_percent_define(]$1[)])],
+                         [$2])])
 
 # b4_percent_define_get_loc(VARIABLE)
 # -----------------------------------
@@ -686,7 +723,21 @@ m4_define([b4_percent_define_get_loc],
           [m4_pushdef([b4_loc], m4_indir([b4_percent_define_loc(]$1[)]))dnl
 b4_loc[]dnl
 m4_popdef([b4_loc])],
-          [b4_fatal([[b4_percent_define_get_loc: undefined %%define variable '%s']], [$1])])])
+          [b4_fatal([[$0: undefined %%define variable '%s']], [$1])])])
+
+# b4_percent_define_get_kind(VARIABLE)
+# ------------------------------------
+# Get the kind (code, keyword, string) of VARIABLE, i.e., how its
+# value was defined (braces, not delimiters, quotes).
+#
+# If the %define variable VARIABLE is undefined, complain fatally
+# since that's a Bison or skeleton error.  Don't record this as a
+# Bison usage of VARIABLE as there's no reason to suspect that the
+# user-supplied value has yet influenced the output.
+m4_define([b4_percent_define_get_kind],
+[m4_ifdef([b4_percent_define_kind(]$1[)],
+          [m4_indir([b4_percent_define_kind(]$1[)])],
+          [b4_fatal([[$0: undefined %%define variable '%s']], [$1])])])
 
 # b4_percent_define_get_syncline(VARIABLE)
 # ----------------------------------------
@@ -703,7 +754,20 @@ m4_popdef([b4_loc])],
 m4_define([b4_percent_define_get_syncline],
 [m4_ifdef([b4_percent_define_syncline(]$1[)],
           [m4_indir([b4_percent_define_syncline(]$1[)])],
-          [b4_fatal([[b4_percent_define_get_syncline: undefined %%define variable '%s']], [$1])])])
+          [b4_fatal([[$0: undefined %%define variable '%s']], [$1])])])
+
+# b4_percent_define_ifdef_(VARIABLE, IF-TRUE, [IF-FALSE])
+# ------------------------------------------------------
+# If the %define variable VARIABLE is defined, expand IF-TRUE, else expand
+# IF-FALSE.  Don't record usage of VARIABLE.
+#
+# For example:
+#
+#   b4_percent_define_ifdef_([[foo]], [[it's defined]], [[it's undefined]])
+m4_define([b4_percent_define_ifdef_],
+[m4_ifdef([b4_percent_define(]$1[)],
+          [$2],
+          [$3])])
 
 # b4_percent_define_ifdef(VARIABLE, IF-TRUE, [IF-FALSE])
 # ------------------------------------------------------
@@ -716,9 +780,9 @@ m4_define([b4_percent_define_get_syncline],
 #
 #   b4_percent_define_ifdef([[foo]], [[it's defined]], [[it's undefined]])
 m4_define([b4_percent_define_ifdef],
-[m4_ifdef([b4_percent_define(]$1[)],
-          [b4_percent_define_use([$1])$2],
-          [$3])])
+[b4_percent_define_ifdef_([$1],
+                         [b4_percent_define_use([$1])$2],
+                         [$3])])
 
 
 ## --------- ##
@@ -747,11 +811,11 @@ m4_define([b4_percent_define_flag_if],
                                            [[invalid value for %%define Boolean variable '%s']],
                                            [$1])],
                            [[b4_percent_define_flag_if($1)]])])],
-  [b4_fatal([[b4_percent_define_flag_if: undefined %%define variable '%s']], [$1])])])
+  [b4_fatal([[$0: undefined %%define variable '%s']], [$1])])])
 
 
-# b4_percent_define_default(VARIABLE, DEFAULT)
-# --------------------------------------------
+# b4_percent_define_default(VARIABLE, DEFAULT, [KIND = keyword])
+# --------------------------------------------------------------
 # Mimic muscle_percent_define_default in ../src/muscle-tab.h exactly.  That is,
 # if the %define variable VARIABLE is undefined, set its value to DEFAULT.
 # Don't record this as a Bison usage of VARIABLE as there's no reason to
@@ -761,8 +825,10 @@ m4_define([b4_percent_define_flag_if],
 #
 #   b4_percent_define_default([[foo]], [[default value]])
 m4_define([b4_percent_define_default],
-[m4_ifndef([b4_percent_define(]$1[)],
+[b4_percent_define_ifdef_([$1], [],
            [m4_define([b4_percent_define(]$1[)], [$2])dnl
+            m4_define([b4_percent_define_kind(]$1[)],
+                      [m4_default([$3], [keyword])])dnl
             m4_define([b4_percent_define_loc(]$1[)],
                       [[[[<skeleton default value>:-1.-1]],
                         [[<skeleton default value>:-1.-1]]]])dnl
@@ -772,8 +838,8 @@ m4_define([b4_percent_define_default],
 # b4_percent_define_if_define(NAME, [VARIABLE = NAME])
 # ----------------------------------------------------
 # Define b4_NAME_if that executes its $1 or $2 depending whether
-# VARIABLE was %defined.  The characters `.' and `-' in VARIABLE are mapped
-# to `_'.
+# VARIABLE was %defined.  The characters '.' and `-' in VARIABLE are mapped
+# to '_'.
 m4_define([b4_percent_define_if_define_],
 [m4_define(m4_bpatsubst([b4_$1_if], [[-.]], [_]),
            [b4_percent_define_flag_if(m4_default([$2], [$1]),
@@ -783,6 +849,21 @@ m4_define([b4_percent_define_if_define],
 b4_percent_define_if_define_([$1], [$2], $[1], $[2])])
 
 
+# b4_percent_define_check_kind(VARIABLE, KIND, [DIAGNOSTIC = complain])
+# ---------------------------------------------------------------------
+m4_define([b4_percent_define_check_kind],
+[b4_percent_define_ifdef_([$1],
+  [m4_if(b4_percent_define_get_kind([$1]), [$2], [],
+    [b4_error([m4_default([$3], [complain])],
+              b4_percent_define_get_loc([$1]),
+              [m4_case([$2],
+                 [code], [[%%define variable '%s' requires '{...}' values]],
+                 [keyword], [[%%define variable '%s' requires keyword values]],
+                 [string], [[%%define variable '%s' requires '"..."' values]])],
+              [$1])])])dnl
+])
+
+
 # b4_percent_define_check_values(VALUES)
 # --------------------------------------
 # Mimic muscle_percent_define_check_values in ../src/muscle-tab.h exactly
@@ -804,8 +885,9 @@ m4_define([b4_percent_define_check_values],
             [_b4_percent_define_check_values(b4_sublist)])])
 
 m4_define([_b4_percent_define_check_values],
-[m4_ifdef([b4_percent_define(]$1[)],
-  [m4_pushdef([b4_good_value], [0])dnl
+[b4_percent_define_ifdef_([$1],
+  [b4_percent_define_check_kind(]$1[, [keyword], [deprecated])dnl
+   m4_pushdef([b4_good_value], [0])dnl
    m4_if($#, 1, [],
          [m4_foreach([b4_value], m4_dquote(m4_shift($@)),
                      [m4_if(m4_indir([b4_percent_define(]$1[)]), b4_value,
@@ -820,7 +902,7 @@ m4_define([_b4_percent_define_check_values],
                                      [[accepted value: '%s']],
                                      m4_dquote(b4_value))])])dnl
    m4_popdef([b4_good_value])],
-  [b4_fatal([[b4_percent_define_check_values: undefined %%define variable '%s']], [$1])])])
+  [b4_fatal([[$0: undefined %%define variable '%s']], [$1])])])
 
 # b4_percent_code_get([QUALIFIER])
 # --------------------------------
@@ -861,10 +943,6 @@ m4_define([b4_percent_code_ifdef],
 ## Common variables.  ##
 ## ------------------ ##
 
-# Default values for %define.
-# ---------------------------
-# If the api.token.prefix, it is empty.
-m4_percent_define_default([[api.token.prefix]], [[]])
 
 # b4_parse_assert_if([IF-ASSERTIONS-ARE-USED], [IF-NOT])
 # b4_parse_trace_if([IF-DEBUG-TRACES-ARE-ENABLED], [IF-NOT])
@@ -904,9 +982,11 @@ b4_error_verbose_if([m4_define([b4_token_table_flag], [1])])
 # b4_variant_if([IF-VARIANT-ARE-USED], [IF-NOT])
 # ----------------------------------------------
 b4_percent_define_if_define([variant])
-m4_case(b4_percent_define_get([[api.value.type]]),
-        [variant], [m4_define([b4_variant_flag], [[1]])],
-                   [m4_define([b4_variant_flag], [[0]])])
+m4_define([b4_variant_flag], [[0]])
+b4_percent_define_ifdef([[api.value.type]],
+   [m4_case(b4_percent_define_get_kind([[api.value.type]]), [keyword],
+            [m4_case(b4_percent_define_get([[api.value.type]]), [variant],
+                    [m4_define([b4_variant_flag], [[1]])])])])
 b4_define_flag_if([variant])
 
 
@@ -941,10 +1021,43 @@ m4_define_default([b4_parse_param], [])
 m4_define_default([b4_location_initial_column], [1])
 m4_define_default([b4_location_initial_line],   [1])
 
-# Sanity checks.
+
+## --------------- ##
+## Sanity checks.  ##
+## --------------- ##
+
+# api.location.prefix={...} (Java and C++).
+b4_percent_define_check_kind([api.location.type], [code], [deprecated])
+
+# api.position.prefix={...} (Java).
+b4_percent_define_check_kind([api.position.type], [code], [deprecated])
+
+# api.prefix >< %name-prefix.
+b4_percent_define_check_kind([api.prefix], [code], [deprecated])
 b4_percent_define_ifdef([api.prefix],
 [m4_ifdef([b4_prefix],
 [b4_complain_at(b4_percent_define_get_loc([api.prefix]),
                 [['%s' and '%s' cannot be used together]],
                 [%name-prefix],
                 [%define api.prefix])])])
+
+# api.token.prefix={...}
+# Make it a warning for those who used betas of Bison 3.0.
+b4_percent_define_check_kind([api.token.prefix], [code], [deprecated])
+
+# api.value.type >< %union.
+b4_percent_define_ifdef([api.value.type],
+[m4_ifdef([b4_union_members],
+[b4_complain_at(b4_percent_define_get_loc([api.value.type]),
+                [['%s' and '%s' cannot be used together]],
+                [%union],
+                [%define api.value.type])])])
+
+# api.value.type=union >< %yacc.
+b4_percent_define_ifdef([api.value.type],
+[m4_if(b4_percent_define_get([api.value.type]), [union],
+[b4_yacc_if(dnl
+[b4_complain_at(b4_percent_define_get_loc([api.value.type]),
+                [['%s' and '%s' cannot be used together]],
+                [%yacc],
+                [%define api.value.type "union"])])])])

data/c++.m4

@@ -25,6 +25,12 @@ m4_include(b4_pkgdatadir/[c.m4])
 m4_define([b4_comment],
 [b4_comment_([$1], [$2// ], [$2// ])])
 
+## -------- ##
+## Checks.  ##
+## -------- ##
+
+b4_percent_define_check_kind([api.namespace], [code], [deprecated])
+b4_percent_define_check_kind([parser_class_name], [code], [deprecated])
 
 ## ---------------- ##
 ## Default values.  ##
@@ -38,6 +44,7 @@ b4_percent_define_default([[parser_class_name]], [[parser]])
 # b4_percent_define_default([[api.location.type]], [[location]])
 
 b4_percent_define_default([[filename_type]], [[std::string]])
+# Make it a warning for those who used betas of Bison 3.0.
 b4_percent_define_default([[api.namespace]], m4_defn([b4_prefix]))
 
 b4_percent_define_default([[global_tokens_and_yystype]], [[false]])
@@ -54,8 +61,8 @@ b4_percent_define_default([[define_location_comparison]],
 m4_define([b4_namespace_ref], [b4_percent_define_get([[api.namespace]])])
 
 
-# Don't permit an empty b4_namespace_ref.  Any `::parser::foo' appended to it
-# would compile as an absolute reference with `parser' in the global namespace.
+# Don't permit an empty b4_namespace_ref.  Any '::parser::foo' appended to it
+# would compile as an absolute reference with 'parser' in the global namespace.
 # b4_namespace_open would open an anonymous namespace and thus establish
 # internal linkage.  This would compile.  However, it's cryptic, and internal
 # linkage for the parser would be specified in all translation units that
@@ -112,19 +119,24 @@ m4_define([b4_token_enums],
 ## Semantic Values.  ##
 ## ----------------- ##
 
-# b4_semantic_type_declare
-# ------------------------
+
+
+# b4_value_type_declare
+# ---------------------
 # Declare semantic_type.
-m4_define([b4_semantic_type_declare],
+m4_define([b4_value_type_declare],
+[b4_value_type_setup[]dnl
 [    /// Symbol semantic values.
-m4_ifdef([b4_stype],
-[    union semantic_type
+]m4_bmatch(b4_percent_define_get_kind([[api.value.type]]),
+[code],
+[[    typedef ]b4_percent_define_get([[api.value.type]])[ semantic_type;]],
+[m4_bmatch(b4_percent_define_get([[api.value.type]]),
+[union\|union-directive],
+[[    union semantic_type
     {
-b4_user_stype
-    };],
-[m4_if(b4_tag_seen_flag, 0,
-[[    typedef int semantic_type;]],
-[[    typedef ]b4_api_PREFIX[STYPE semantic_type;]])])])
+    ]b4_user_union_members[
+    };]])])dnl
+])
 
 
 # b4_public_types_declare
@@ -133,7 +145,7 @@ b4_user_stype
 # Depending on %define token_lex, may be output in the header or source file.
 m4_define([b4_public_types_declare],
 [[#ifndef ]b4_api_PREFIX[STYPE
-]b4_semantic_type_declare[
+]b4_value_type_declare[
 #else
     typedef ]b4_api_PREFIX[STYPE semantic_type;
 #endif]b4_locations_if([
@@ -520,3 +532,13 @@ m4_define([b4_yylloc_default_define],
     while (/*CONSTCOND*/ false)
 # endif
 ]])
+
+## -------- ##
+## Checks.  ##
+## -------- ##
+
+b4_token_ctor_if([b4_variant_if([],
+  [b4_fatal_at(b4_percent_define_get_loc(api.token.constructor),
+               [cannot use '%s' without '%s'],
+               [%define api.token.constructor],
+               [%define api.value.type variant]))])])

data/c.m4

@@ -150,7 +150,7 @@ m4_popdef([$1])dnl
 
 # b4_parse_param_use([VAL], [LOC])
 # --------------------------------
-# `YYUSE' VAL, LOC if locations are enabled, and all the parse-params.
+# 'YYUSE' VAL, LOC if locations are enabled, and all the parse-params.
 m4_define([b4_parse_param_use],
 [m4_ifvaln([$1], [  YYUSE ([$1]);])dnl
 b4_locations_if([m4_ifvaln([$2], [  YYUSE ([$2]);])])dnl
@@ -182,7 +182,7 @@ m4_define([b4_int_type],
 # b4_int_type_for(NAME)
 # ---------------------
 # Return the smallest int type able to handle numbers ranging from
-# `NAME_min' to `NAME_max' (included).
+# 'NAME_min' to 'NAME_max' (included).
 m4_define([b4_int_type_for],
 [b4_int_type($1_min, $1_max)])
 
@@ -199,6 +199,69 @@ m4_define([b4_table_value_equals],
        [(!!(($2) == ($3)))])])
 
 
+## ----------------- ##
+## Compiler issues.  ##
+## ----------------- ##
+
+# b4_attribute_define
+# -------------------
+# Provide portable compiler "attributes".
+m4_define([b4_attribute_define],
+[#ifndef YY_ATTRIBUTE
+# if (defined __GNUC__                                               \
+      && (2 < __GNUC__ || (__GNUC__ == 2 && 96 <= __GNUC_MINOR__)))  \
+     || defined __SUNPRO_C && 0x5110 <= __SUNPRO_C
+#  define YY_ATTRIBUTE(Spec) __attribute__(Spec)
+# else
+#  define YY_ATTRIBUTE(Spec) /* empty */
+# endif
+#endif
+
+#ifndef YY_ATTRIBUTE_PURE
+# define YY_ATTRIBUTE_PURE   YY_ATTRIBUTE ((__pure__))
+#endif
+
+#ifndef YY_ATTRIBUTE_UNUSED
+# define YY_ATTRIBUTE_UNUSED YY_ATTRIBUTE ((__unused__))
+#endif
+
+#if !defined _Noreturn \
+     && (!defined __STDC_VERSION__ || __STDC_VERSION__ < 201112)
+# if defined _MSC_VER && 1200 <= _MSC_VER
+#  define _Noreturn __declspec (noreturn)
+# else
+#  define _Noreturn YY_ATTRIBUTE ((__noreturn__))
+# endif
+#endif
+
+/* Suppress unused-variable warnings by "using" E.  */
+#if ! defined lint || defined __GNUC__
+# define YYUSE(E) ((void) (E))
+#else
+# define YYUSE(E) /* empty */
+#endif
+
+#if defined __GNUC__ && 407 <= __GNUC__ * 100 + __GNUC_MINOR__
+/* Suppress an incorrect diagnostic about yylval being uninitialized.  */
+# define YY_IGNORE_MAYBE_UNINITIALIZED_BEGIN \
+    _Pragma ("GCC diagnostic push") \
+    _Pragma ("GCC diagnostic ignored \"-Wuninitialized\"")\
+    _Pragma ("GCC diagnostic ignored \"-Wmaybe-uninitialized\"")
+# define YY_IGNORE_MAYBE_UNINITIALIZED_END \
+    _Pragma ("GCC diagnostic pop")
+#else
+# define YY_INITIAL_VALUE(Value) Value
+#endif
+#ifndef YY_IGNORE_MAYBE_UNINITIALIZED_BEGIN
+# define YY_IGNORE_MAYBE_UNINITIALIZED_BEGIN
+# define YY_IGNORE_MAYBE_UNINITIALIZED_END
+#endif
+#ifndef YY_INITIAL_VALUE
+# define YY_INITIAL_VALUE(Value) /* Nothing. */
+#endif
+])
+
+
 ## ---------##
 ## Values.  ##
 ## ---------##
@@ -206,14 +269,14 @@ m4_define([b4_table_value_equals],
 
 # b4_null_define
 # --------------
-# Portability issues: define a YY_NULL appropriate for the current
+# Portability issues: define a YY_NULLPTR appropriate for the current
 # language (C, C++98, or C++11).
 m4_define([b4_null_define],
-[# ifndef YY_NULL
+[# ifndef YY_NULLPTR
 #  if defined __cplusplus && 201103L <= __cplusplus
-#   define YY_NULL nullptr
+#   define YY_NULLPTR nullptr
 #  else
-#   define YY_NULL 0
+#   define YY_NULLPTR 0
 #  endif
 # endif[]dnl
 ])
@@ -222,7 +285,7 @@ m4_define([b4_null_define],
 # b4_null
 # -------
 # Return a null pointer constant.
-m4_define([b4_null], [YY_NULL])
+m4_define([b4_null], [YY_NULLPTR])
 
 # b4_integral_parser_table_define(TABLE-NAME, CONTENT, COMMENT)
 # -------------------------------------------------------------
@@ -421,12 +484,9 @@ m4_ifset([b4_parse_param], [, b4_parse_param]))[
     yymsg = "Deleting";
   YY_SYMBOL_PRINT (yymsg, yytype, yyvaluep, yylocationp);
 
-  switch (yytype)
-    {
-]b4_symbol_foreach([b4_symbol_destructor])dnl
-[      default:
-        break;
-    }
+  YY_IGNORE_MAYBE_UNINITIALIZED_BEGIN
+  ]b4_symbol_actions([destructor])[
+  YY_IGNORE_MAYBE_UNINITIALIZED_END
 }]dnl
 ])
 
@@ -436,9 +496,9 @@ m4_ifset([b4_parse_param], [, b4_parse_param]))[
 # Define the "yy_symbol_print" function.
 m4_define_default([b4_yy_symbol_print_define],
 [[
-/*--------------------------------.
-| Print this symbol on YYOUTPUT.  |
-`--------------------------------*/
+/*----------------------------------------.
+| Print this symbol's value on YYOUTPUT.  |
+`----------------------------------------*/
 
 ]b4_function_define([yy_symbol_value_print],
     [static void],
@@ -459,12 +519,7 @@ m4_if(b4_skeleton, ["yacc.c"],
     YYPRINT (yyoutput, yytoknum[yytype], *yyvaluep);
 # endif
 ]])dnl
-[  switch (yytype)
-    {
-]b4_symbol_foreach([b4_symbol_printer])dnl
-[      default:
-        break;
-    }
+  b4_symbol_actions([printer])[
 }
 
 
@@ -492,28 +547,154 @@ b4_locations_if([, yylocationp])[]b4_user_args[);
 }]dnl
 ])
 
+
+## ---------------- ##
+## api.value.type.  ##
+## ---------------- ##
+
+
+# ---------------------- #
+# api.value.type=union.  #
+# ---------------------- #
+
+# b4_symbol_type_register(SYMBOL-NUM)
+# -----------------------------------
+# Symbol SYMBOL-NUM has a type (for variant) instead of a type-tag.
+# Extend the definition of %union's body with a field of that type,
+# and extend the symbol's "type" field to point to the field name,
+# instead of the type name.
+m4_define([b4_symbol_type_register],
+[m4_define([b4_symbol($1, type_tag)],
+           [b4_symbol_if([$1], [has_id],
+                         [b4_symbol([$1], [id])],
+                         [yytype_[]b4_symbol([$1], [number])])])dnl
+m4_append([b4_user_union_members],
+m4_expand([
+  b4_symbol_tag_comment([$1])dnl
+  b4_symbol([$1], [type]) b4_symbol([$1], [type_tag]);]))
+])
+
+
+# b4_type_define_tag(SYMBOL1-NUM, ...)
+# ------------------------------------
+# For the batch of symbols SYMBOL1-NUM... (which all have the same
+# type), enhance the %union definition for each of them, and set
+# there "type" field to the field tag name, instead of the type name.
+m4_define([b4_type_define_tag],
+[b4_symbol_if([$1], [has_type],
+              [m4_map([b4_symbol_type_register], [$@])])
+])
+
+
+# b4_symbol_value_union(VAL, [TYPE])
+# ----------------------------------
+# Same of b4_symbol_value, but when api.value.type=union.
+m4_define([b4_symbol_value_union],
+[m4_ifval([$2],
+          [(*($2*)(&$1))],
+          [$1])])
+])
+
+
+# b4_value_type_setup_union
+# -------------------------
+# Setup support for api.value.type=union.  Symbols are defined with a
+# type instead of a union member name: build the corresponding union,
+# and give the symbols their tag.
+m4_define([b4_value_type_setup_union],
+[m4_define([b4_union_members])
+b4_type_foreach([b4_type_define_tag])
+m4_copy_force([b4_symbol_value_union], [b4_symbol_value])
+])
+
+
+# ---------------- #
+# api.value.type.  #
+# ---------------- #
+
+
+# b4_value_type_setup_variant
+# ---------------------------
+# Setup support for api.value.type=variant.  By default, fail, specialized
+# by other skeletons.
+m4_define([b4_value_type_setup_variant],
+[b4_complain_at(b4_percent_define_get_loc([[api.value.type]]),
+                [['%s' does not support '%s']],
+                [b4_skeleton],
+                [%define api.value.type variant])])
+
+
+# _b4_value_type_setup_keyword
+# ----------------------------
+# api.value.type is defined with a keyword/string syntax.  Check if
+# that is properly defined, and prepare its use.
+m4_define([_b4_value_type_setup_keyword],
+[b4_percent_define_check_values([[[[api.value.type]],
+                                  [[none]],
+                                  [[union]],
+                                  [[union-directive]],
+                                  [[variant]],
+                                  [[yystype]]]])dnl
+m4_case(b4_percent_define_get([[api.value.type]]),
+        [union],   [b4_value_type_setup_union],
+        [variant], [b4_value_type_setup_variant])])
+
+
+# b4_value_type_setup
+# -------------------
+# Check if api.value.type is properly defined, and possibly prepare
+# its use.
+b4_define_silent([b4_value_type_setup],
+[# Define default value.
+b4_percent_define_ifdef([[api.value.type]], [],
+[# %union => api.value.type=union-directive
+m4_ifdef([b4_union_members],
+[m4_define([b4_percent_define_kind(api.value.type)], [keyword])
+m4_define([b4_percent_define(api.value.type)], [union-directive])],
+[# no tag seen => api.value.type={int}
+m4_if(b4_tag_seen_flag, 0,
+[m4_define([b4_percent_define_kind(api.value.type)], [code])
+m4_define([b4_percent_define(api.value.type)], [int])],
+[# otherwise api.value.type=yystype
+m4_define([b4_percent_define_kind(api.value.type)], [keyword])
+m4_define([b4_percent_define(api.value.type)], [yystype])])])])
+
+# Set up.
+m4_bmatch(b4_percent_define_get_kind([[api.value.type]]),
+   [keyword\|string], [_b4_value_type_setup_keyword])
+])
+
+
 ## -------------- ##
 ## Declarations.  ##
 ## -------------- ##
 
+
 # b4_value_type_define
 # --------------------
 m4_define([b4_value_type_define],
-[[/* Value type.  */
-#if ! defined ]b4_api_PREFIX[STYPE && ! defined ]b4_api_PREFIX[STYPE_IS_DECLARED
-]m4_ifdef([b4_stype],
-[[typedef union ]b4_union_name[ ]b4_api_PREFIX[STYPE;
-union ]b4_union_name[
-{
-]b4_user_stype[
-};
-# define ]b4_api_PREFIX[STYPE_IS_TRIVIAL 1]],
-[m4_if(b4_tag_seen_flag, 0,
-[[typedef int ]b4_api_PREFIX[STYPE;
-# define ]b4_api_PREFIX[STYPE_IS_TRIVIAL 1]])])[
+[b4_value_type_setup[]dnl
+/* Value type.  */
+m4_bmatch(b4_percent_define_get_kind([[api.value.type]]),
+[code],
+[[#if ! defined ]b4_api_PREFIX[STYPE && ! defined ]b4_api_PREFIX[STYPE_IS_DECLARED
+typedef ]b4_percent_define_get([[api.value.type]])[ ]b4_api_PREFIX[STYPE;
+# define ]b4_api_PREFIX[STYPE_IS_TRIVIAL 1
 # define ]b4_api_PREFIX[STYPE_IS_DECLARED 1
 #endif
-]])
+]],
+[m4_bmatch(b4_percent_define_get([[api.value.type]]),
+[union\|union-directive],
+[[#if ! defined ]b4_api_PREFIX[STYPE && ! defined ]b4_api_PREFIX[STYPE_IS_DECLARED
+typedef union ]b4_union_name[ ]b4_api_PREFIX[STYPE;
+union ]b4_union_name[
+{
+]b4_user_union_members[
+};
+# define ]b4_api_PREFIX[STYPE_IS_TRIVIAL 1
+# define ]b4_api_PREFIX[STYPE_IS_DECLARED 1
+#endif
+]])])])
 
 
 # b4_location_type_define
@@ -549,7 +730,7 @@ b4_pure_if([], [[extern ]b4_api_PREFIX[STYPE ]b4_prefix[lval;
 
 
 # b4_YYDEBUG_define
-# ------------------
+# -----------------
 m4_define([b4_YYDEBUG_define],
 [[/* Debug traces.  */
 ]m4_if(b4_api_prefix, [yy],
@@ -621,7 +802,7 @@ m4_define([b4_yy_location_print_define],
 
 /* Print *YYLOCP on YYO.  Private, do not rely on its existence. */
 
-__attribute__((__unused__))
+YY_ATTRIBUTE_UNUSED
 ]b4_function_define([yy_location_print_],
     [static unsigned],
                [[FILE *yyo],                    [yyo]],

data/glr.c

@@ -246,13 +246,6 @@ b4_percent_code_get[]dnl
 # endif
 #endif
 
-/* Suppress unused-variable warnings by "using" E.  */
-#ifdef __GNUC__
-# define YYUSE(E) ((void) (E))
-#else
-# define YYUSE(E) /* empty */
-#endif
-
 #ifndef YYFREE
 # define YYFREE free
 #endif
@@ -281,17 +274,7 @@ b4_percent_code_get[]dnl
 # define YYLONGJMP(Env, Val) (longjmp (Env, Val), YYASSERT (0))
 #endif
 
-/*-----------------.
-| GCC extensions.  |
-`-----------------*/
-
-#ifndef __attribute__
-/* This feature is available in gcc versions 2.5 and later.  */
-# if (! defined __GNUC__ || __GNUC__ < 2 \
-      || (__GNUC__ == 2 && __GNUC_MINOR__ < 5))
-#  define __attribute__(Spec) /* empty */
-# endif
-#endif
+]b4_attribute_define[
 
 #ifndef YYASSERT
 # define YYASSERT(Condition) ((void) ((Condition) || (abort (), 0)))
@@ -462,9 +445,9 @@ int yydebug;
 
 struct yyGLRStack;
 static void yypstack (struct yyGLRStack* yystackp, size_t yyk)
-  __attribute__ ((__unused__));
+  YY_ATTRIBUTE_UNUSED;
 static void yypdumpstack (struct yyGLRStack* yystackp)
-  __attribute__ ((__unused__));
+  YY_ATTRIBUTE_UNUSED;
 
 #else /* !]b4_api_PREFIX[DEBUG */
 
@@ -686,19 +669,15 @@ struct yyGLRStack {
 static void yyexpandGLRStack (yyGLRStack* yystackp);
 #endif
 
-static void yyFail (yyGLRStack* yystackp]b4_pure_formals[, const char* yymsg)
-  __attribute__ ((__noreturn__));
-static void
+static _Noreturn void
 yyFail (yyGLRStack* yystackp]b4_pure_formals[, const char* yymsg)
 {
-  if (yymsg != YY_NULL)
+  if (yymsg != YY_NULLPTR)
     yyerror (]b4_yyerror_args[yymsg);
   YYLONGJMP (yystackp->yyexception_buffer, 1);
 }
 
-static void yyMemoryExhausted (yyGLRStack* yystackp)
-  __attribute__ ((__noreturn__));
-static void
+static _Noreturn void
 yyMemoryExhausted (yyGLRStack* yystackp)
 {
   YYLONGJMP (yystackp->yyexception_buffer, 2);
@@ -719,7 +698,7 @@ yytokenName (yySymbol yytoken)
 /** Fill in YYVSP[YYLOW1 .. YYLOW0-1] from the chain of states starting
  *  at YYVSP[YYLOW0].yystate.yypred.  Leaves YYVSP[YYLOW1].yystate.yypred
  *  containing the pointer to the next state in the chain.  */
-static void yyfillin (yyGLRStackItem *, int, int) __attribute__ ((__unused__));
+static void yyfillin (yyGLRStackItem *, int, int) YY_ATTRIBUTE_UNUSED;
 static void
 yyfillin (yyGLRStackItem *yyvsp, int yylow0, int yylow1)
 {
@@ -736,7 +715,7 @@ yyfillin (yyGLRStackItem *yyvsp, int yylow0, int yylow1)
       else
         /* The effect of using yysval or yyloc (in an immediate rule) is
          * undefined.  */
-        yyvsp[i].yystate.yysemantics.yyfirstVal = YY_NULL;]b4_locations_if([[
+        yyvsp[i].yystate.yysemantics.yyfirstVal = YY_NULLPTR;]b4_locations_if([[
       yyvsp[i].yystate.yyloc = s->yyloc;]])[
       s = yyvsp[i].yystate.yypred = s->yypred;
     }
@@ -746,7 +725,7 @@ yyfillin (yyGLRStackItem *yyvsp, int yylow0, int yylow1)
  * YYVSP[YYLOW1 .. *YYLOW-1] as in yyfillin and set *YYLOW = YYLOW1.
  * For convenience, always return YYLOW1.  */
 static inline int yyfill (yyGLRStackItem *, int *, int, yybool)
-     __attribute__ ((__unused__));
+     YY_ATTRIBUTE_UNUSED;
 static inline int
 yyfill (yyGLRStackItem *yyvsp, int *yylow, int yylow1, yybool yynormal)
 {
@@ -768,8 +747,7 @@ yyuserAction (yyRuleNum yyn, size_t yyrhslen, yyGLRStackItem* yyvsp,
               yyGLRStack* yystackp,
               YYSTYPE* yyvalp]b4_locuser_formals[)
 {
-  yybool yynormal __attribute__ ((__unused__)) =
-    (yystackp->yysplitPoint == YY_NULL);
+  yybool yynormal YY_ATTRIBUTE_UNUSED = (yystackp->yysplitPoint == YY_NULLPTR);
   int yylow;
 ]b4_parse_param_use([yyvalp], [yylocp])dnl
 [  YYUSE (yyrhslen);
@@ -853,12 +831,10 @@ yydestroyGLRState (char const *yymsg, yyGLRState *yys]b4_user_formals[)
       if (yydebug)
         {
           if (yys->yysemantics.yyfirstVal)
-            YYFPRINTF (stderr, "%s unresolved ", yymsg);
+            YYFPRINTF (stderr, "%s unresolved", yymsg);
           else
-            YYFPRINTF (stderr, "%s incomplete ", yymsg);
-          yy_symbol_print (stderr, yystos[yys->yylrState],
-                           YY_NULL]b4_locuser_args([&yys->yyloc])[);
-          YYFPRINTF (stderr, "\n");
+            YYFPRINTF (stderr, "%s incomplete", yymsg);
+          YY_SYMBOL_PRINT ("", yystos[yys->yylrState], YY_NULLPTR, &yys->yyloc);
         }
 #endif
 
@@ -934,14 +910,18 @@ yygetLRActions (yyStateNum yystate, int yytoken,
     }
 }
 
+/** Compute post-reduction state.
+ * \param yystate   the current state
+ * \param yysym     the nonterminal to push on the stack
+ */
 static inline yyStateNum
-yyLRgotoState (yyStateNum yystate, yySymbol yylhs)
+yyLRgotoState (yyStateNum yystate, yySymbol yysym)
 {
-  int yyr = yypgoto[yylhs - YYNTOKENS] + yystate;
+  int yyr = yypgoto[yysym - YYNTOKENS] + yystate;
   if (0 <= yyr && yyr <= YYLAST && yycheck[yyr] == yystate)
     return yytable[yyr];
   else
-    return yydefgoto[yylhs - YYNTOKENS];
+    return yydefgoto[yysym - YYNTOKENS];
 }
 
 static inline yybool
@@ -983,6 +963,7 @@ yyaddDeferredAction (yyGLRStack* yystackp, size_t yyk, yyGLRState* yystate,
 {
   yySemanticOption* yynewOption =
     &yynewGLRStackItem (yystackp, yyfalse)->yyoption;
+  YYASSERT (!yynewOption->yyisState);
   yynewOption->yystate = yyrhs;
   yynewOption->yyrule = yyrule;
   if (yystackp->yytops.yylookaheadNeeds[yyk])
@@ -1010,7 +991,7 @@ yyinitStateSet (yyGLRStateSet* yyset)
   yyset->yystates = (yyGLRState**) YYMALLOC (16 * sizeof yyset->yystates[0]);
   if (! yyset->yystates)
     return yyfalse;
-  yyset->yystates[0] = YY_NULL;
+  yyset->yystates[0] = YY_NULLPTR;
   yyset->yylookaheadNeeds =
     (yybool*) YYMALLOC (16 * sizeof yyset->yylookaheadNeeds[0]);
   if (! yyset->yylookaheadNeeds)
@@ -1040,8 +1021,8 @@ yyinitGLRStack (yyGLRStack* yystackp, size_t yysize)
   if (!yystackp->yyitems)
     return yyfalse;
   yystackp->yynextFree = yystackp->yyitems;
-  yystackp->yysplitPoint = YY_NULL;
-  yystackp->yylastDeleted = YY_NULL;
+  yystackp->yysplitPoint = YY_NULLPTR;
+  yystackp->yylastDeleted = YY_NULLPTR;
   return yyinitStateSet (&yystackp->yytops);
 }
 
@@ -1080,10 +1061,10 @@ yyexpandGLRStack (yyGLRStack* yystackp)
         {
           yyGLRState* yys0 = &yyp0->yystate;
           yyGLRState* yys1 = &yyp1->yystate;
-          if (yys0->yypred != YY_NULL)
+          if (yys0->yypred != YY_NULLPTR)
             yys1->yypred =
               YYRELOC (yyp0, yyp1, yys0->yypred, yystate);
-          if (! yys0->yyresolved && yys0->yysemantics.yyfirstVal != YY_NULL)
+          if (! yys0->yyresolved && yys0->yysemantics.yyfirstVal != YY_NULLPTR)
             yys1->yysemantics.yyfirstVal =
               YYRELOC (yyp0, yyp1, yys0->yysemantics.yyfirstVal, yyoption);
         }
@@ -1091,18 +1072,18 @@ yyexpandGLRStack (yyGLRStack* yystackp)
         {
           yySemanticOption* yyv0 = &yyp0->yyoption;
           yySemanticOption* yyv1 = &yyp1->yyoption;
-          if (yyv0->yystate != YY_NULL)
+          if (yyv0->yystate != YY_NULLPTR)
             yyv1->yystate = YYRELOC (yyp0, yyp1, yyv0->yystate, yystate);
-          if (yyv0->yynext != YY_NULL)
+          if (yyv0->yynext != YY_NULLPTR)
             yyv1->yynext = YYRELOC (yyp0, yyp1, yyv0->yynext, yyoption);
         }
     }
-  if (yystackp->yysplitPoint != YY_NULL)
+  if (yystackp->yysplitPoint != YY_NULLPTR)
     yystackp->yysplitPoint = YYRELOC (yystackp->yyitems, yynewItems,
-                                 yystackp->yysplitPoint, yystate);
+                                      yystackp->yysplitPoint, yystate);
 
   for (yyn = 0; yyn < yystackp->yytops.yysize; yyn += 1)
-    if (yystackp->yytops.yystates[yyn] != YY_NULL)
+    if (yystackp->yytops.yystates[yyn] != YY_NULLPTR)
       yystackp->yytops.yystates[yyn] =
         YYRELOC (yystackp->yyitems, yynewItems,
                  yystackp->yytops.yystates[yyn], yystate);
@@ -1126,7 +1107,7 @@ yyfreeGLRStack (yyGLRStack* yystackp)
 static inline void
 yyupdateSplit (yyGLRStack* yystackp, yyGLRState* yys)
 {
-  if (yystackp->yysplitPoint != YY_NULL && yystackp->yysplitPoint > yys)
+  if (yystackp->yysplitPoint != YY_NULLPTR && yystackp->yysplitPoint > yys)
     yystackp->yysplitPoint = yys;
 }
 
@@ -1134,9 +1115,9 @@ yyupdateSplit (yyGLRStack* yystackp, yyGLRState* yys)
 static inline void
 yymarkStackDeleted (yyGLRStack* yystackp, size_t yyk)
 {
-  if (yystackp->yytops.yystates[yyk] != YY_NULL)
+  if (yystackp->yytops.yystates[yyk] != YY_NULLPTR)
     yystackp->yylastDeleted = yystackp->yytops.yystates[yyk];
-  yystackp->yytops.yystates[yyk] = YY_NULL;
+  yystackp->yytops.yystates[yyk] = YY_NULLPTR;
 }
 
 /** Undelete the last stack in *YYSTACKP that was marked as deleted.  Can
@@ -1145,12 +1126,12 @@ yymarkStackDeleted (yyGLRStack* yystackp, size_t yyk)
 static void
 yyundeleteLastStack (yyGLRStack* yystackp)
 {
-  if (yystackp->yylastDeleted == YY_NULL || yystackp->yytops.yysize != 0)
+  if (yystackp->yylastDeleted == YY_NULLPTR || yystackp->yytops.yysize != 0)
     return;
   yystackp->yytops.yystates[0] = yystackp->yylastDeleted;
   yystackp->yytops.yysize = 1;
   YYDPRINTF ((stderr, "Restoring last deleted stack as stack #0.\n"));
-  yystackp->yylastDeleted = YY_NULL;
+  yystackp->yylastDeleted = YY_NULLPTR;
 }
 
 static inline void
@@ -1160,7 +1141,7 @@ yyremoveDeletes (yyGLRStack* yystackp)
   yyi = yyj = 0;
   while (yyj < yystackp->yytops.yysize)
     {
-      if (yystackp->yytops.yystates[yyi] == YY_NULL)
+      if (yystackp->yytops.yystates[yyi] == YY_NULLPTR)
         {
           if (yyi == yyj)
             {
@@ -1218,12 +1199,13 @@ yyglrShiftDefer (yyGLRStack* yystackp, size_t yyk, yyStateNum yylrState,
                  size_t yyposn, yyGLRState* yyrhs, yyRuleNum yyrule)
 {
   yyGLRState* yynewState = &yynewGLRStackItem (yystackp, yytrue)->yystate;
+  YYASSERT (yynewState->yyisState);
 
   yynewState->yylrState = yylrState;
   yynewState->yyposn = yyposn;
   yynewState->yyresolved = yyfalse;
   yynewState->yypred = yystackp->yytops.yystates[yyk];
-  yynewState->yysemantics.yyfirstVal = YY_NULL;
+  yynewState->yysemantics.yyfirstVal = YY_NULLPTR;
   yystackp->yytops.yystates[yyk] = yynewState;
 
   /* Invokes YY_RESERVE_GLRSTACK.  */
@@ -1283,7 +1265,7 @@ yydoAction (yyGLRStack* yystackp, size_t yyk, yyRuleNum yyrule,
 {
   int yynrhs = yyrhsLength (yyrule);
 
-  if (yystackp->yysplitPoint == YY_NULL)
+  if (yystackp->yysplitPoint == YY_NULLPTR)
     {
       /* Standard special case: single stack.  */
       yyGLRStackItem* yyrhs = (yyGLRStackItem*) yystackp->yytops.yystates[yyk];
@@ -1335,14 +1317,13 @@ yyglrReduce (yyGLRStack* yystackp, size_t yyk, yyRuleNum yyrule,
 {
   size_t yyposn = yystackp->yytops.yystates[yyk]->yyposn;
 
-  if (yyforceEval || yystackp->yysplitPoint == YY_NULL)
+  if (yyforceEval || yystackp->yysplitPoint == YY_NULLPTR)
     {
-      YYRESULTTAG yyflag;
-      YYSTYPE yysval;]b4_locations_if([
-      YYLTYPE yyloc;])[
+      YYSTYPE yysval;]b4_locations_if([[
+      YYLTYPE yyloc;]])[
 
-      yyflag = yydoAction (yystackp, yyk, yyrule, &yysval]b4_locuser_args([&yyloc])[);
-      if (yyflag == yyerr && yystackp->yysplitPoint != YY_NULL)
+      YYRESULTTAG yyflag = yydoAction (yystackp, yyk, yyrule, &yysval]b4_locuser_args([&yyloc])[);
+      if (yyflag == yyerr && yystackp->yysplitPoint != YY_NULLPTR)
         {
           YYDPRINTF ((stderr, "Parse on stack %lu rejected by rule #%d.\n",
                      (unsigned long int) yyk, yyrule - 1));
@@ -1375,7 +1356,7 @@ yyglrReduce (yyGLRStack* yystackp, size_t yyk, yyRuleNum yyrule,
                   "Now in state %d.\n",
                   (unsigned long int) yyk, yyrule - 1, yynewLRState));
       for (yyi = 0; yyi < yystackp->yytops.yysize; yyi += 1)
-        if (yyi != yyk && yystackp->yytops.yystates[yyi] != YY_NULL)
+        if (yyi != yyk && yystackp->yytops.yystates[yyi] != YY_NULLPTR)
           {
             yyGLRState *yysplit = yystackp->yysplitPoint;
             yyGLRState *yyp = yystackp->yytops.yystates[yyi];
@@ -1402,7 +1383,7 @@ yyglrReduce (yyGLRStack* yystackp, size_t yyk, yyRuleNum yyrule,
 static size_t
 yysplitStack (yyGLRStack* yystackp, size_t yyk)
 {
-  if (yystackp->yysplitPoint == YY_NULL)
+  if (yystackp->yysplitPoint == YY_NULLPTR)
     {
       YYASSERT (yyk == 0);
       yystackp->yysplitPoint = yystackp->yytops.yystates[yyk];
@@ -1412,7 +1393,7 @@ yysplitStack (yyGLRStack* yystackp, size_t yyk)
       yyGLRState** yynewStates;
       yybool* yynewLookaheadNeeds;
 
-      yynewStates = YY_NULL;
+      yynewStates = YY_NULLPTR;
 
       if (yystackp->yytops.yycapacity
           > (YYSIZEMAX / (2 * sizeof yynewStates[0])))
@@ -1423,7 +1404,7 @@ yysplitStack (yyGLRStack* yystackp, size_t yyk)
         (yyGLRState**) YYREALLOC (yystackp->yytops.yystates,
                                   (yystackp->yytops.yycapacity
                                    * sizeof yynewStates[0]));
-      if (yynewStates == YY_NULL)
+      if (yynewStates == YY_NULLPTR)
         yyMemoryExhausted (yystackp);
       yystackp->yytops.yystates = yynewStates;
 
@@ -1431,7 +1412,7 @@ yysplitStack (yyGLRStack* yystackp, size_t yyk)
         (yybool*) YYREALLOC (yystackp->yytops.yylookaheadNeeds,
                              (yystackp->yytops.yycapacity
                               * sizeof yynewLookaheadNeeds[0]));
-      if (yynewLookaheadNeeds == YY_NULL)
+      if (yynewLookaheadNeeds == YY_NULLPTR)
         yyMemoryExhausted (yystackp);
       yystackp->yytops.yylookaheadNeeds = yynewLookaheadNeeds;
     }
@@ -1495,9 +1476,9 @@ yymergeOptionSets (yySemanticOption* yyy0, yySemanticOption* yyy1)
           yySemanticOption* yyz1 = yys1->yysemantics.yyfirstVal;
           while (yytrue)
             {
-              if (yyz1 == *yyz0p || yyz1 == YY_NULL)
+              if (yyz1 == *yyz0p || yyz1 == YY_NULLPTR)
                 break;
-              else if (*yyz0p == YY_NULL)
+              else if (*yyz0p == YY_NULLPTR)
                 {
                   *yyz0p = yyz1;
                   break;
@@ -1618,7 +1599,7 @@ yyreportTree (yySemanticOption* yyx, int yyindent)
 
   for (yyi = yynrhs, yys = yyx->yystate; 0 < yyi; yyi -= 1, yys = yys->yypred)
     yystates[yyi] = yys;
-  if (yys == YY_NULL)
+  if (yys == YY_NULLPTR)
     {
       yyleftmost_state.yyposn = 0;
       yystates[0] = &yyleftmost_state;
@@ -1689,7 +1670,7 @@ yyresolveLocations (yyGLRState* yys1, int yyn1,
           yyGLRStackItem yyrhsloc[1 + YYMAXRHS];
           int yynrhs;
           yySemanticOption *yyoption = yys1->yysemantics.yyfirstVal;
-          YYASSERT (yyoption != YY_NULL);
+          YYASSERT (yyoption != YY_NULLPTR);
           yynrhs = yyrhsLength (yyoption->yyrule);
           if (yynrhs > 0)
             {
@@ -1748,7 +1729,7 @@ yyresolveValue (yyGLRState* yys, yyGLRStack* yystackp]b4_user_formals[)
   YYRESULTTAG yyflag;]b4_locations_if([
   YYLTYPE *yylocp = &yys->yyloc;])[
 
-  for (yypp = &yyoptionList->yynext; *yypp != YY_NULL; )
+  for (yypp = &yyoptionList->yynext; *yypp != YY_NULLPTR; )
     {
       yySemanticOption* yyp = *yypp;
 
@@ -1790,7 +1771,7 @@ yyresolveValue (yyGLRState* yys, yyGLRStack* yystackp]b4_user_formals[)
       int yyprec = yydprec[yybest->yyrule];
       yyflag = yyresolveAction (yybest, yystackp, &yysval]b4_locuser_args[);
       if (yyflag == yyok)
-        for (yyp = yybest->yynext; yyp != YY_NULL; yyp = yyp->yynext)
+        for (yyp = yybest->yynext; yyp != YY_NULLPTR; yyp = yyp->yynext)
           {
             if (yyprec == yydprec[yyp->yyrule])
               {
@@ -1817,14 +1798,14 @@ yyresolveValue (yyGLRState* yys, yyGLRStack* yystackp]b4_user_formals[)
       yys->yysemantics.yysval = yysval;
     }
   else
-    yys->yysemantics.yyfirstVal = YY_NULL;
+    yys->yysemantics.yyfirstVal = YY_NULLPTR;
   return yyflag;
 }
 
 static YYRESULTTAG
 yyresolveStack (yyGLRStack* yystackp]b4_user_formals[)
 {
-  if (yystackp->yysplitPoint != YY_NULL)
+  if (yystackp->yysplitPoint != YY_NULLPTR)
     {
       yyGLRState* yys;
       int yyn;
@@ -1844,10 +1825,10 @@ yycompressStack (yyGLRStack* yystackp)
 {
   yyGLRState* yyp, *yyq, *yyr;
 
-  if (yystackp->yytops.yysize != 1 || yystackp->yysplitPoint == YY_NULL)
+  if (yystackp->yytops.yysize != 1 || yystackp->yysplitPoint == YY_NULLPTR)
     return;
 
-  for (yyp = yystackp->yytops.yystates[0], yyq = yyp->yypred, yyr = YY_NULL;
+  for (yyp = yystackp->yytops.yystates[0], yyq = yyp->yypred, yyr = YY_NULLPTR;
        yyp != yystackp->yysplitPoint;
        yyr = yyp, yyp = yyq, yyq = yyp->yypred)
     yyp->yypred = yyr;
@@ -1855,10 +1836,10 @@ yycompressStack (yyGLRStack* yystackp)
   yystackp->yyspaceLeft += yystackp->yynextFree - yystackp->yyitems;
   yystackp->yynextFree = ((yyGLRStackItem*) yystackp->yysplitPoint) + 1;
   yystackp->yyspaceLeft -= yystackp->yynextFree - yystackp->yyitems;
-  yystackp->yysplitPoint = YY_NULL;
-  yystackp->yylastDeleted = YY_NULL;
+  yystackp->yysplitPoint = YY_NULLPTR;
+  yystackp->yylastDeleted = YY_NULLPTR;
 
-  while (yyr != YY_NULL)
+  while (yyr != YY_NULLPTR)
     {
       yystackp->yynextFree->yystate = *yyr;
       yyr = yyr->yypred;
@@ -1873,7 +1854,7 @@ static YYRESULTTAG
 yyprocessOneStack (yyGLRStack* yystackp, size_t yyk,
                    size_t yyposn]b4_pure_formals[)
 {
-  while (yystackp->yytops.yystates[yyk] != YY_NULL)
+  while (yystackp->yytops.yystates[yyk] != YY_NULLPTR)
     {
       yyStateNum yystate = yystackp->yytops.yystates[yyk]->yylrState;
       YYDPRINTF ((stderr, "Stack %lu Entering state %d\n",
@@ -1995,13 +1976,13 @@ yyreportSyntaxError (yyGLRStack* yystackp]b4_user_formals[)
 #else
   {
   yySymbol yytoken = yychar == YYEMPTY ? YYEMPTY : YYTRANSLATE (yychar);
-  size_t yysize0 = yytnamerr (YY_NULL, yytokenName (yytoken));
+  size_t yysize0 = yytnamerr (YY_NULLPTR, yytokenName (yytoken));
   size_t yysize = yysize0;
   yybool yysize_overflow = yyfalse;
-  char* yymsg = YY_NULL;
+  char* yymsg = YY_NULLPTR;
   enum { YYERROR_VERBOSE_ARGS_MAXIMUM = 5 };
   /* Internationalized format string. */
-  const char *yyformat = YY_NULL;
+  const char *yyformat = YY_NULLPTR;
   /* Arguments of yyformat. */
   char const *yyarg[YYERROR_VERBOSE_ARGS_MAXIMUM];
   /* Number of reported tokens (one for the "unexpected", one per
@@ -2057,7 +2038,7 @@ yyreportSyntaxError (yyGLRStack* yystackp]b4_user_formals[)
                   }
                 yyarg[yycount++] = yytokenName (yyx);
                 {
-                  size_t yysz = yysize + yytnamerr (YY_NULL, yytokenName (yyx));
+                  size_t yysz = yysize + yytnamerr (YY_NULLPTR, yytokenName (yyx));
                   yysize_overflow |= yysz < yysize;
                   yysize = yysz;
                 }
@@ -2135,7 +2116,7 @@ yyrecoverSyntaxError (yyGLRStack* yystackp]b4_user_formals[)
       {
         yySymbol yytoken;
         if (yychar == YYEOF)
-          yyFail (yystackp][]b4_lpure_args[, YY_NULL);
+          yyFail (yystackp][]b4_lpure_args[, YY_NULLPTR);
         if (yychar != YYEMPTY)
           {]b4_locations_if([[
             /* We throw away the lookahead, but the error range
@@ -2176,10 +2157,10 @@ yyrecoverSyntaxError (yyGLRStack* yystackp]b4_user_formals[)
 
   /* Reduce to one stack.  */
   for (yyk = 0; yyk < yystackp->yytops.yysize; yyk += 1)
-    if (yystackp->yytops.yystates[yyk] != YY_NULL)
+    if (yystackp->yytops.yystates[yyk] != YY_NULLPTR)
       break;
   if (yyk >= yystackp->yytops.yysize)
-    yyFail (yystackp][]b4_lpure_args[, YY_NULL);
+    yyFail (yystackp][]b4_lpure_args[, YY_NULLPTR);
   for (yyk += 1; yyk < yystackp->yytops.yysize; yyk += 1)
     yymarkStackDeleted (yystackp, yyk);
   yyremoveDeletes (yystackp);
@@ -2187,7 +2168,7 @@ yyrecoverSyntaxError (yyGLRStack* yystackp]b4_user_formals[)
 
   /* Now pop stack until we find a state that shifts the error token.  */
   yystackp->yyerrState = 3;
-  while (yystackp->yytops.yystates[0] != YY_NULL)
+  while (yystackp->yytops.yystates[0] != YY_NULLPTR)
     {
       yyGLRState *yys = yystackp->yytops.yystates[0];
       yyj = yypact[yys->yylrState];
@@ -2211,14 +2192,14 @@ yyrecoverSyntaxError (yyGLRStack* yystackp]b4_user_formals[)
             }
         }]b4_locations_if([[
       yystackp->yyerror_range[1].yystate.yyloc = yys->yyloc;]])[
-      if (yys->yypred != YY_NULL)
+      if (yys->yypred != YY_NULLPTR)
         yydestroyGLRState ("Error: popping", yys]b4_user_args[);
       yystackp->yytops.yystates[0] = yys->yypred;
       yystackp->yynextFree -= 1;
       yystackp->yyspaceLeft += 1;
     }
-  if (yystackp->yytops.yystates[0] == YY_NULL)
-    yyFail (yystackp][]b4_lpure_args[, YY_NULL);
+  if (yystackp->yytops.yystates[0] == YY_NULLPTR)
+    yyFail (yystackp][]b4_lpure_args[, YY_NULLPTR);
 }
 
 #define YYCHK1(YYE)                                                          \
@@ -2461,7 +2442,7 @@ b4_dollar_popdef])[]dnl
                   {
                     yyGLRState *yys = yystates[yyk];
 ]b4_locations_if([[                 yystack.yyerror_range[1].yystate.yyloc = yys->yyloc;]]
-)[                  if (yys->yypred != YY_NULL)
+)[                  if (yys->yypred != YY_NULLPTR)
                       yydestroyGLRState ("Cleanup: popping", yys]b4_user_args[);
                     yystates[yyk] = yys->yypred;
                     yystack.yynextFree -= 1;
@@ -2493,7 +2474,7 @@ yy_yypstack (yyGLRState* yys)
 static void
 yypstates (yyGLRState* yyst)
 {
-  if (yyst == YY_NULL)
+  if (yyst == YY_NULLPTR)
     YYFPRINTF (stderr, "<null>");
   else
     yy_yypstack (yyst);
@@ -2507,7 +2488,7 @@ yypstack (yyGLRStack* yystackp, size_t yyk)
 }
 
 #define YYINDEX(YYX)                                                         \
-    ((YYX) == YY_NULL ? -1 : (yyGLRStackItem*) (YYX) - yystackp->yyitems)
+    ((YYX) == YY_NULLPTR ? -1 : (yyGLRStackItem*) (YYX) - yystackp->yyitems)
 
 
 static void
@@ -2521,6 +2502,8 @@ yypdumpstack (yyGLRStack* yystackp)
                  (unsigned long int) (yyp - yystackp->yyitems));
       if (*(yybool *) yyp)
         {
+          YYASSERT (yyp->yystate.yyisState);
+          YYASSERT (yyp->yyoption.yyisState);
           YYFPRINTF (stderr, "Res: %d, LR State: %d, posn: %lu, pred: %ld",
                      yyp->yystate.yyresolved, yyp->yystate.yylrState,
                      (unsigned long int) yyp->yystate.yyposn,
@@ -2532,6 +2515,8 @@ yypdumpstack (yyGLRStack* yystackp)
         }
       else
         {
+          YYASSERT (!yyp->yystate.yyisState);
+          YYASSERT (!yyp->yyoption.yyisState);
           YYFPRINTF (stderr, "Option. rule: %d, state: %ld, next: %ld",
                      yyp->yyoption.yyrule - 1,
                      (long int) YYINDEX (yyp->yyoption.yystate),

data/glr.cc

@@ -43,12 +43,6 @@
 #   user must initialize the first positions (in particular the
 #   filename member).
 
-b4_token_ctor_if([b4_variant_if([],
-  [b4_fatal_at(b4_percent_define_get_loc(api.token.constructor),
-               [cannot use '%s' without '%s'],
-               [%define api.token.constructor],
-               [%define api.value.type variant]))])])
-
 # We require a pure interface.
 m4_define([b4_pure_flag],      [1])
 
@@ -193,12 +187,7 @@ m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl
     std::ostream& yyoutput = debug_stream ();
     std::ostream& yyo = yyoutput;
     YYUSE (yyo);
-    switch (yytype)
-      {
-]b4_symbol_foreach([b4_symbol_printer])dnl
-[        default:
-          break;
-      }
+    ]b4_symbol_actions([printer])[
   }
 
 

data/java.m4

@@ -103,7 +103,7 @@ m4_define([b4_int_type],
 # b4_int_type_for(NAME)
 # ---------------------
 # Return the smallest int type able to handle numbers ranging from
-# `NAME_min' to `NAME_max' (included).
+# 'NAME_min' to 'NAME_max' (included).
 m4_define([b4_int_type_for],
 [b4_int_type($1_min, $1_max)])
 
@@ -169,6 +169,22 @@ m4_define([b4_predicate_case], [  case $1:
     ])
 
 
+## -------- ##
+## Checks.  ##
+## -------- ##
+
+b4_percent_define_check_kind([[api.value.type]],    [code], [deprecated])
+
+b4_percent_define_check_kind([[annotations]],       [code], [deprecated])
+b4_percent_define_check_kind([[extends]],           [code], [deprecated])
+b4_percent_define_check_kind([[implements]],        [code], [deprecated])
+b4_percent_define_check_kind([[init_throws]],       [code], [deprecated])
+b4_percent_define_check_kind([[lex_throws]],        [code], [deprecated])
+b4_percent_define_check_kind([[parser_class_name]], [code], [deprecated])
+b4_percent_define_check_kind([[throws]],            [code], [deprecated])
+
+
+
 ## ---------------- ##
 ## Default values.  ##
 ## ---------------- ##

data/lalr1.cc

@@ -17,6 +17,8 @@
 
 m4_include(b4_pkgdatadir/[c++.m4])
 
+# api.value.type=variant is valid.
+m4_define([b4_value_type_setup_variant])
 
 # b4_integral_parser_table_declare(TABLE-NAME, CONTENT, COMMENT)
 # --------------------------------------------------------------
@@ -38,13 +40,14 @@ m4_define([b4_integral_parser_table_define],
   };dnl
 ])
 
-
 # b4_symbol_value_template(VAL, [TYPE])
 # -------------------------------------
 # Same as b4_symbol_value, but used in a template method.  It makes
-# a difference when using variants.
+# a difference when using variants.  Note that b4_value_type_setup_union
+# overrides b4_symbol_value, so we must override it again.
 m4_copy([b4_symbol_value], [b4_symbol_value_template])
-
+m4_append([b4_value_type_setup_union],
+          [m4_copy_force([b4_symbol_value_union], [b4_symbol_value_template])])
 
 # b4_lhs_value([TYPE])
 # --------------------
@@ -154,6 +157,7 @@ m4_define([b4_shared_declarations],
 ]b4_bison_locations_if([[# include "location.hh"]])])[
 ]b4_variant_if([b4_variant_includes])[
 
+]b4_attribute_define[
 ]b4_YYDEBUG_define[
 
 ]b4_namespace_open[
@@ -180,14 +184,14 @@ b4_location_define])])[
 
 #if ]b4_api_PREFIX[DEBUG
     /// The current debugging stream.
-    std::ostream& debug_stream () const;
+    std::ostream& debug_stream () const YY_ATTRIBUTE_PURE;
     /// Set the current debugging stream.
     void set_debug_stream (std::ostream &);
 
     /// Type for debugging levels.
     typedef int debug_level_type;
     /// The current debugging level.
-    debug_level_type debug_level () const;
+    debug_level_type debug_level () const YY_ATTRIBUTE_PURE;
     /// Set the current debugging level.
     void set_debug_level (debug_level_type l);
 #endif
@@ -201,6 +205,10 @@ b4_location_define])])[
     void error (const syntax_error& err);
 
   private:
+    /// This class is not copyable.
+    ]b4_parser_class_name[ (const ]b4_parser_class_name[&);
+    ]b4_parser_class_name[& operator= (const ]b4_parser_class_name[&);
+
     /// State numbers.
     typedef int state_type;
 
@@ -212,8 +220,8 @@ b4_location_define])])[
 
     /// Compute post-reduction state.
     /// \param yystate   the current state
-    /// \param yylhs     the nonterminal to push on the stack
-    state_type yy_lr_goto_state_ (state_type yystate, int yylhs);
+    /// \param yysym     the nonterminal to push on the stack
+    state_type yy_lr_goto_state_ (state_type yystate, int yysym);
 
     /// Whether the given \c yypact_ value indicates a defaulted state.
     /// \param yyvalue   the value to check
@@ -260,7 +268,7 @@ b4_location_define])])[
     /// \brief Reclaim the memory associated to a symbol.
     /// \param yymsg     Why this token is reclaimed.
     ///                  If null, print nothing.
-    /// \param s         The symbol.
+    /// \param yysym     The symbol.
     template <typename Base>
     void yy_destroy_ (const char* yymsg, basic_symbol<Base>& yysym) const;
 
@@ -334,13 +342,13 @@ b4_location_define])])[
     enum
     {
       yyeof_ = 0,
-      yylast_ = ]b4_last[,           //< Last index in yytable_.
-      yynnts_ = ]b4_nterms_number[,  //< Number of nonterminal symbols.
+      yylast_ = ]b4_last[,     ///< Last index in yytable_.
+      yynnts_ = ]b4_nterms_number[,  ///< Number of nonterminal symbols.
       yyempty_ = -2,
-      yyfinal_ = ]b4_final_state_number[, //< Termination state number.
+      yyfinal_ = ]b4_final_state_number[, ///< Termination state number.
       yyterror_ = 1,
       yyerrcode_ = 256,
-      yyntokens_ = ]b4_tokens_number[    //< Number of tokens.
+      yyntokens_ = ]b4_tokens_number[  ///< Number of tokens.
     };
 
 ]b4_parse_param_vars[
@@ -591,13 +599,7 @@ m4_if(b4_prefix, [yy], [],
       YY_SYMBOL_PRINT (yymsg, yysym);]b4_variant_if([], [
 
     // User destructor.
-    symbol_number_type yytype = yysym.type_get ();
-    switch (yytype)
-      {
-]b4_symbol_foreach([b4_symbol_destructor])dnl
-[       default:
-          break;
-      }])[
+    b4_symbol_actions([destructor], [yysym.type_get ()])])[
   }
 
 #if ]b4_api_PREFIX[DEBUG
@@ -612,12 +614,7 @@ m4_if(b4_prefix, [yy], [],
     yyo << (yytype < yyntokens_ ? "token" : "nterm")
         << ' ' << yytname_[yytype] << " ("]b4_locations_if([
         << yysym.location << ": "])[;
-    switch (yytype)
-      {
-]b4_symbol_foreach([b4_symbol_printer])dnl
-[       default:
-          break;
-      }
+    ]b4_symbol_actions([printer])[
     yyo << ')';
   }
 #endif
@@ -674,13 +671,13 @@ m4_if(b4_prefix, [yy], [],
 #endif // ]b4_api_PREFIX[DEBUG
 
   inline ]b4_parser_class_name[::state_type
-  ]b4_parser_class_name[::yy_lr_goto_state_ (state_type yystate, int yylhs)
+  ]b4_parser_class_name[::yy_lr_goto_state_ (state_type yystate, int yysym)
   {
-    int yyr = yypgoto_[yylhs - yyntokens_] + yystate;
+    int yyr = yypgoto_[yysym - yyntokens_] + yystate;
     if (0 <= yyr && yyr <= yylast_ && yycheck_[yyr] == yystate)
       return yytable_[yyr];
     else
-      return yydefgoto_[yylhs - yyntokens_];
+      return yydefgoto_[yysym - yyntokens_];
   }
 
   inline bool
@@ -703,6 +700,7 @@ m4_if(b4_prefix, [yy], [],
 
     // State.
     int yyn;
+    /// Length of the RHS of the rule being reduced.
     int yylen = 0;
 
     // Error handling.
@@ -715,9 +713,6 @@ m4_if(b4_prefix, [yy], [],
     /// The locations where the error started and ended.
     stack_symbol_type yyerror_range[3];]])[
 
-    /// $$ and @@$.
-    stack_symbol_type yylhs;
-
     /// The return value of parse ().
     int yyresult;
 
@@ -737,8 +732,8 @@ b4_dollar_popdef])[]dnl
        yynewstate, since the latter expects the semantical and the
        location values to have been already stored, initialize these
        stacks with a primary value.  */
-    yystack_ = stack_type (0);
-    yypush_ (YY_NULL, 0, yyla);
+    yystack_.clear ();
+    yypush_ (YY_NULLPTR, 0, yyla);
 
     // A new symbol was pushed on the stack.
   yynewstate:
@@ -818,52 +813,55 @@ b4_dollar_popdef])[]dnl
   `-----------------------------*/
   yyreduce:
     yylen = yyr2_[yyn];
-    yylhs.state = yy_lr_goto_state_(yystack_[yylen].state, yyr1_[yyn]);]b4_variant_if([
-    /* Variants are always initialized to an empty instance of the
-       correct type. The default $$=$1 action is NOT applied when using
-       variants.  */
-    b4_symbol_variant([[yyr1_@{yyn@}]], [yylhs.value], [build])],[
-    /* If YYLEN is nonzero, implement the default value of the action:
-       `$$ = $1'.  Otherwise, use the top of the stack.
+    {
+      stack_symbol_type yylhs;
+      yylhs.state = yy_lr_goto_state_(yystack_[yylen].state, yyr1_[yyn]);]b4_variant_if([
+      /* Variants are always initialized to an empty instance of the
+         correct type. The default '$$ = $1' action is NOT applied
+         when using variants.  */
+      b4_symbol_variant([[yyr1_@{yyn@}]], [yylhs.value], [build])], [
+      /* If YYLEN is nonzero, implement the default value of the
+         action: '$$ = $1'.  Otherwise, use the top of the stack.
 
-       Otherwise, the following line sets YYLHS.VALUE to garbage.
-       This behavior is undocumented and Bison
-       users should not rely upon it.  */
-    if (yylen)
-      yylhs.value = yystack_@{yylen - 1@}.value;
-    else
-      yylhs.value = yystack_@{0@}.value;])[
+         Otherwise, the following line sets YYLHS.VALUE to garbage.
+         This behavior is undocumented and Bison users should not rely
+         upon it.  */
+      if (yylen)
+        yylhs.value = yystack_@{yylen - 1@}.value;
+      else
+        yylhs.value = yystack_@{0@}.value;])[
 ]b4_locations_if([dnl
 [
-    // Compute the default @@$.
-    {
-      slice<stack_symbol_type, stack_type> slice (yystack_, yylen);
-      YYLLOC_DEFAULT (yylhs.location, slice, yylen);
-    }]])[
-
-    // Perform the reduction.
-    YY_REDUCE_PRINT (yyn);
-    try
+      // Compute the default @@$.
       {
-        switch (yyn)
-          {
+        slice<stack_symbol_type, stack_type> slice (yystack_, yylen);
+        YYLLOC_DEFAULT (yylhs.location, slice, yylen);
+      }]])[
+
+      // Perform the reduction.
+      YY_REDUCE_PRINT (yyn);
+      try
+        {
+          switch (yyn)
+            {
 ]b4_user_actions[
-          default:
-            break;
-          }
-      }
-    catch (const syntax_error& yyexc)
-      {
-        error (yyexc);
-        YYERROR;
-      }
-    YY_SYMBOL_PRINT ("-> $$ =", yylhs);
-    yypop_ (yylen);
-    yylen = 0;
-    YY_STACK_PRINT ();
+            default:
+              break;
+            }
+        }
+      catch (const syntax_error& yyexc)
+        {
+          error (yyexc);
+          YYERROR;
+        }
+      YY_SYMBOL_PRINT ("-> $$ =", yylhs);
+      yypop_ (yylen);
+      yylen = 0;
+      YY_STACK_PRINT ();
 
-    // Shift the result of the reduction.
-    yypush_ (YY_NULL, yylhs);
+      // Shift the result of the reduction.
+      yypush_ (YY_NULLPTR, yylhs);
+    }
     goto yynewstate;
 
   /*--------------------------------------.
@@ -910,10 +908,7 @@ b4_dollar_popdef])[]dnl
        code.  */
     if (false)
       goto yyerrorlab;]b4_locations_if([[
-    yyerror_range[1].location = yystack_[yylen - 1].location;]])b4_variant_if([[
-    /* $$ was initialized before running the user action.  */
-    YY_SYMBOL_PRINT ("Error: discarding", yylhs);
-    yylhs.~stack_symbol_type();]])[
+    yyerror_range[1].location = yystack_[yylen - 1].location;]])[
     /* Do not reclaim the symbols of the rule whose action triggered
        this YYERROR.  */
     yypop_ (yylen);
@@ -992,11 +987,11 @@ b4_dollar_popdef])[]dnl
         // Do not try to display the values of the reclaimed symbols,
         // as their printer might throw an exception.
         if (!yyempty)
-          yy_destroy_ (YY_NULL, yyla);
+          yy_destroy_ (YY_NULLPTR, yyla);
 
         while (1 < yystack_.size ())
           {
-            yy_destroy_ (YY_NULL, yystack_[0]);
+            yy_destroy_ (YY_NULLPTR, yystack_[0]);
             yypop_ ();
           }
         throw;
@@ -1078,7 +1073,7 @@ b4_error_verbose_if([state_type yystate, symbol_number_type yytoken],
           }
       }
 
-    char const* yyformat = YY_NULL;
+    char const* yyformat = YY_NULLPTR;
     switch (yycount)
       {
 #define YYCASE_(N, S)                         \

data/lalr1.java

@@ -20,7 +20,8 @@ m4_include(b4_pkgdatadir/[java.m4])
 b4_defines_if([b4_fatal([%s: %%defines does not make sense in Java],
               [b4_skeleton])])
 
-# We don't depend on %debug in Java, but pacify warnings about non-used flags.
+# We do not depend on %debug in Java, but pacify warnings about
+# non-used flags.
 b4_parse_trace_if([0], [0])
 
 m4_define([b4_symbol_no_destructor_assert],
@@ -30,6 +31,57 @@ m4_define([b4_symbol_no_destructor_assert],
                         [b4_symbol_action_location([$1], [destructor])])])])
 b4_symbol_foreach([b4_symbol_no_destructor_assert])
 
+# Setup some macros for api.push-pull.
+b4_percent_define_default([[api.push-pull]], [[pull]])
+b4_percent_define_check_values([[[[api.push-pull]],
+                                 [[pull]], [[push]], [[both]]]])
+
+# Define m4 conditional macros that encode the value
+# of the api.push-pull flag.
+b4_define_flag_if([pull]) m4_define([b4_pull_flag], [[1]])
+b4_define_flag_if([push]) m4_define([b4_push_flag], [[1]])
+m4_case(b4_percent_define_get([[api.push-pull]]),
+        [pull], [m4_define([b4_push_flag], [[0]])],
+        [push], [m4_define([b4_pull_flag], [[0]])])
+
+# Define a macro to be true when api.push-pull has the value "both".
+m4_define([b4_both_if],[b4_push_if([b4_pull_if([$1],[$2])],[$2])])
+
+# Handle BISON_USE_PUSH_FOR_PULL for the test suite.  So that push parsing
+# tests function as written, do not let BISON_USE_PUSH_FOR_PULL modify the
+# behavior of Bison at all when push parsing is already requested.
+b4_define_flag_if([use_push_for_pull])
+b4_use_push_for_pull_if([
+  b4_push_if([m4_define([b4_use_push_for_pull_flag], [[0]])],
+             [m4_define([b4_push_flag], [[1]])])])
+
+# Define a macro to encapsulate the parse state variables.
+# This allows them to be defined either in parse() when doing
+# pull parsing, or as class instance variable when doing push parsing.
+m4_define([b4_define_state],[[
+    /* Lookahead and lookahead in internal form.  */
+    int yychar = yyempty_;
+    int yytoken = 0;
+
+    /* State.  */
+    int yyn = 0;
+    int yylen = 0;
+    int yystate = 0;
+    YYStack yystack = new YYStack ();
+    int label = YYNEWSTATE;
+
+    /* Error handling.  */
+    int yynerrs_ = 0;
+    ]b4_locations_if([/* The location where the error started.  */
+    b4_location_type yyerrloc = null;
+
+    /* Location. */
+    b4_location_type yylloc = new b4_location_type (null, null);])[
+
+    /* Semantic value of the lookahead.  */
+    ]b4_yystype[ yylval = null;
+]])
+
 b4_output_begin([b4_parser_file_name])
 b4_copyright([Skeleton implementation for Bison LALR(1) parsers in Java],
              [2007-2013])
@@ -55,7 +107,9 @@ b4_percent_define_get3([implements], [ implements ])[
 {
   ]b4_identification[
 ]b4_error_verbose_if([[
-  /** True if verbose error messages are enabled.  */
+  /**
+   * True if verbose error messages are enabled.
+   */
   private boolean yyErrorVerbose = true;
 
   /**
@@ -76,18 +130,24 @@ b4_locations_if([[
    * A class defining a pair of positions.  Positions, defined by the
    * <code>]b4_position_type[</code> class, denote a point in the input.
    * Locations represent a part of the input through the beginning
-   * and ending positions.  */
+   * and ending positions.
+   */
   public class ]b4_location_type[ {
-    /** The first, inclusive, position in the range.  */
+    /**
+     * The first, inclusive, position in the range.
+     */
     public ]b4_position_type[ begin;
 
-    /** The first position beyond the range.  */
+    /**
+     * The first position beyond the range.
+     */
     public ]b4_position_type[ end;
 
     /**
      * Create a <code>]b4_location_type[</code> denoting an empty range located at
      * a given point.
-     * @@param loc The position at which the range is anchored.  */
+     * @@param loc The position at which the range is anchored.
+     */
     public ]b4_location_type[ (]b4_position_type[ loc) {
       this.begin = this.end = loc;
     }
@@ -95,7 +155,8 @@ b4_locations_if([[
     /**
      * Create a <code>]b4_location_type[</code> from the endpoints of the range.
      * @@param begin The first position included in the range.
-     * @@param end   The first position beyond the range.  */
+     * @@param end   The first position beyond the range.
+     */
     public ]b4_location_type[ (]b4_position_type[ begin, ]b4_position_type[ end) {
       this.begin = begin;
       this.end = end;
@@ -104,7 +165,8 @@ b4_locations_if([[
     /**
      * Print a representation of the location.  For this to be correct,
      * <code>]b4_position_type[</code> should override the <code>equals</code>
-     * method.  */
+     * method.
+     */
     public String toString () {
       if (begin.equals (end))
         return begin.toString ();
@@ -136,24 +198,28 @@ b4_locations_if([[
 
     ]b4_locations_if([[/**
      * Method to retrieve the beginning position of the last scanned token.
-     * @@return the position at which the last scanned token starts.  */
+     * @@return the position at which the last scanned token starts.
+     */
     ]b4_position_type[ getStartPos ();
 
     /**
      * Method to retrieve the ending position of the last scanned token.
-     * @@return the first position beyond the last scanned token.  */
+     * @@return the first position beyond the last scanned token.
+     */
     ]b4_position_type[ getEndPos ();]])[
 
     /**
      * Method to retrieve the semantic value of the last scanned token.
-     * @@return the semantic value of the last scanned token.  */
+     * @@return the semantic value of the last scanned token.
+     */
     ]b4_yystype[ getLVal ();
 
     /**
      * Entry point for the scanner.  Returns the token identifier corresponding
      * to the next token and prepares to return the semantic value
      * ]b4_locations_if([and beginning/ending positions ])[of the token.
-     * @@return the token identifier corresponding to the next token. */
+     * @@return the token identifier corresponding to the next token.
+     */
     int yylex () ]b4_maybe_throws([b4_lex_throws])[;
 
     /**
@@ -162,7 +228,8 @@ b4_locations_if([[
      *
      * ]b4_locations_if([[@@param loc The location of the element to which the
      *                error message is related]])[
-     * @@param msg The string for the error message.  */
+     * @@param msg The string for the error message.
+     */
      void yyerror (]b4_locations_if([b4_location_type[ loc, ]])[String msg);]
   }
 
@@ -170,7 +237,9 @@ b4_locations_if([[
 ]b4_percent_code_get([[lexer]])[
   }
 
-  ]])[/** The object doing lexical analysis for us.  */
+  ]])[/**
+   * The object doing lexical analysis for us.
+   */
   private Lexer yylexer;
   ]
   b4_parse_param_vars
@@ -336,46 +405,74 @@ b4_lexer_if([[
 
   /**
    * Returned by a Bison action in order to stop the parsing process and
-   * return success (<tt>true</tt>).  */
+   * return success (<tt>true</tt>).
+   */
   public static final int YYACCEPT = 0;
 
   /**
    * Returned by a Bison action in order to stop the parsing process and
-   * return failure (<tt>false</tt>).  */
+   * return failure (<tt>false</tt>).
+   */
   public static final int YYABORT = 1;
 
+]b4_push_if([
+  /**
+   * Returned by a Bison action in order to request a new token.
+   */
+  public static final int YYPUSH_MORE = 4;])[
+
   /**
    * Returned by a Bison action in order to start error recovery without
-   * printing an error message.  */
+   * printing an error message.
+   */
   public static final int YYERROR = 2;
 
-  // Internal return codes that are not supported for user semantic
-  // actions.
+  /**
+   * Internal return codes that are not supported for user semantic
+   * actions.
+   */
   private static final int YYERRLAB = 3;
   private static final int YYNEWSTATE = 4;
   private static final int YYDEFAULT = 5;
   private static final int YYREDUCE = 6;
   private static final int YYERRLAB1 = 7;
   private static final int YYRETURN = 8;
+]b4_push_if([[  private static final int YYGETTOKEN = 9; /* Signify that a new token is expected when doing push-parsing.  */]])[
 
   private int yyerrstatus_ = 0;
 
+]b4_push_if([dnl
+b4_define_state])[
   /**
    * Return whether error recovery is being done.  In this state, the parser
    * reads token until it reaches a known state, and then restarts normal
-   * operation.  */
+   * operation.
+   */
   public final boolean recovering ()
   {
     return yyerrstatus_ == 0;
   }
 
+  /** Compute post-reduction state.
+   * @@param yystate   the current state
+   * @@param yysym     the nonterminal to push on the stack
+   */
+  private int yy_lr_goto_state_ (int yystate, int yysym)
+  {
+    int yyr = yypgoto_[yysym - yyntokens_] + yystate;
+    if (0 <= yyr && yyr <= yylast_ && yycheck_[yyr] == yystate)
+      return yytable_[yyr];
+    else
+      return yydefgoto_[yysym - yyntokens_];
+  }
+
   private int yyaction (int yyn, YYStack yystack, int yylen) ]b4_maybe_throws([b4_throws])[
   {
     ]b4_yystype[ yyval;
     ]b4_locations_if([b4_location_type[ yyloc = yylloc (yystack, yylen);]])[
 
     /* If YYLEN is nonzero, implement the default value of the action:
-       `$$ = $1'.  Otherwise, use the top of the stack.
+       '$$ = $1'.  Otherwise, use the top of the stack.
 
        Otherwise, the following line sets YYVAL to garbage.
        This behavior is undocumented and Bison
@@ -399,14 +496,7 @@ b4_lexer_if([[
     yylen = 0;
 
     /* Shift the result of the reduction.  */
-    yyn = yyr1_[yyn];
-    int yystate = yypgoto_[yyn - yyntokens_] + yystack.stateAt (0);
-    if (0 <= yystate && yystate <= yylast_
-        && yycheck_[yystate] == yystack.stateAt (0))
-      yystate = yytable_[yystate];
-    else
-      yystate = yydefgoto_[yyn - yyntokens_];
-
+    int yystate = yy_lr_goto_state_ (yystack.stateAt (0), yyr1_[yyn]);
     yystack.push (yystate, yyval]b4_locations_if([, yyloc])[);
     return YYNEWSTATE;
   }
@@ -463,6 +553,7 @@ b4_lexer_if([[
               + (yyvaluep == null ? "(null)" : yyvaluep.toString ()) + ")");
   }
 
+]b4_push_if([],[[
   /**
    * Parse input from the scanner that was specified at object construction
    * time.  Return whether the end of the input was reached successfully.
@@ -470,46 +561,53 @@ b4_lexer_if([[
    * @@return <tt>true</tt> if the parsing succeeds.  Note that this does not
    *          imply that there were no syntax errors.
    */
-  public boolean parse () ]b4_maybe_throws([b4_list2([b4_lex_throws], [b4_throws])])[
+   public boolean parse () ]b4_maybe_throws([b4_list2([b4_lex_throws], [b4_throws])])[]])[
+]b4_push_if([
+  /**
+   * Push Parse input from external lexer
+   *
+   * @@param yylextoken current token
+   * @@param yylexval current lval
+]b4_locations_if([   * @@param yylexloc current position])[
+   *
+   * @@return <tt>YYACCEPT, YYABORT, YYPUSH_MORE</tt>
+   */
+  public int push_parse (int yylextoken, b4_yystype yylexval[]b4_locations_if([, b4_location_type yylexloc]))
+      b4_maybe_throws([b4_list2([b4_lex_throws], [b4_throws])])])[
   {
-    /// Lookahead and lookahead in internal form.
-    int yychar = yyempty_;
-    int yytoken = 0;
-
-    /* State.  */
-    int yyn = 0;
-    int yylen = 0;
-    int yystate = 0;
-
-    YYStack yystack = new YYStack ();
-
-    /* Error handling.  */
-    int yynerrs_ = 0;
-    ]b4_locations_if([/// The location where the error started.
-    ]b4_location_type[ yyerrloc = null;
-
-    /// ]b4_location_type[ of the lookahead.
-    ]b4_location_type[ yylloc = new ]b4_location_type[ (null, null);
-
-    /// @@$.
-    ]b4_location_type[ yyloc;])
-
-    /// Semantic value of the lookahead.
-    b4_yystype[ yylval = null;
-
+    ]b4_locations_if([/* @@$.  */
+    b4_location_type yyloc;])[
+]b4_push_if([],[[
+]b4_define_state[
     yycdebug ("Starting parse\n");
     yyerrstatus_ = 0;
 
+    /* Initialize the stack.  */
+    yystack.push (yystate, yylval ]b4_locations_if([, yylloc])[);
 ]m4_ifdef([b4_initial_action], [
 b4_dollar_pushdef([yylval], [], [yylloc])dnl
     /* User initialization code.  */
     b4_user_initial_action
-b4_dollar_popdef])[]dnl
+b4_dollar_popdef[]dnl
+])[
+]])[
+]b4_push_if([[
+    if (!this.push_parse_initialized)
+      {
+        push_parse_initialize ();
+]m4_ifdef([b4_initial_action], [
+b4_dollar_pushdef([yylval], [], [yylloc])dnl
+    /* User initialization code.  */
+    b4_user_initial_action
+b4_dollar_popdef[]dnl
+])[
+        yycdebug ("Starting parse\n");
+        yyerrstatus_ = 0;
+      } else
+        label = YYGETTOKEN;
 
-  [  /* Initialize the stack.  */
-    yystack.push (yystate, yylval]b4_locations_if([, yylloc])[);
-
-    int label = YYNEWSTATE;
+    boolean push_token_consumed = true;
+]])[
     for (;;)
       switch (label)
       {
@@ -522,7 +620,8 @@ b4_dollar_popdef])[]dnl
 
         /* Accept?  */
         if (yystate == yyfinal_)
-          return true;
+          ]b4_push_if([{label = YYACCEPT; break;}],
+                      [return true;])[
 
         /* Take a decision.  First try without lookahead.  */
         yyn = yypact_[yystate];
@@ -531,16 +630,27 @@ b4_dollar_popdef])[]dnl
             label = YYDEFAULT;
             break;
           }
+]b4_push_if([        /* Fall Through */
 
+      case YYGETTOKEN:])[
         /* Read a lookahead token.  */
         if (yychar == yyempty_)
           {
+]b4_push_if([[
+            if (!push_token_consumed)
+              return YYPUSH_MORE;
             yycdebug ("Reading a token: ");
-            yychar = yylexer.yylex ();]
-            b4_locations_if([[
-            yylloc = new ]b4_location_type[(yylexer.getStartPos (),
-                            yylexer.getEndPos ());]])
-            yylval = yylexer.getLVal ();[
+            yychar = yylextoken;
+            yylval = yylexval;]b4_locations_if([
+            yylloc = yylexloc;])[
+            push_token_consumed = false;]])[
+]b4_push_if([],[[
+            yycdebug ("Reading a token: ");
+            yychar = yylexer.yylex ();
+            yylval = yylexer.getLVal ();]b4_locations_if([
+            yylloc = new b4_location_type (yylexer.getStartPos (),
+                            yylexer.getEndPos ());])[
+]])[
           }
 
         /* Convert token to internal form.  */
@@ -637,10 +747,10 @@ b4_dollar_popdef])[]dnl
           {
           /* Return failure if at end of input.  */
           if (yychar == Lexer.EOF)
-            return false;
+            ]b4_push_if([{label = YYABORT; break;}],[return false;])[
           }
         else
-              yychar = yyempty_;
+            yychar = yyempty_;
           }
 
         /* Else will try to reuse lookahead token after shifting the error
@@ -648,9 +758,9 @@ b4_dollar_popdef])[]dnl
         label = YYERRLAB1;
         break;
 
-      /*---------------------------------------------------.
+      /*-------------------------------------------------.
       | errorlab -- error raised explicitly by YYERROR.  |
-      `---------------------------------------------------*/
+      `-------------------------------------------------*/
       case YYERROR:
 
         ]b4_locations_if([yyerrloc = yystack.locationAt (yylen - 1);])[
@@ -682,9 +792,10 @@ b4_dollar_popdef])[]dnl
                   }
               }
 
-            /* Pop the current state because it cannot handle the error token.  */
+            /* Pop the current state because it cannot handle the
+             * error token.  */
             if (yystack.height == 0)
-              return false;
+              ]b4_push_if([{label = YYABORT; break;}],[return false;])[
 
             ]b4_locations_if([yyerrloc = yystack.locationAt (0);])[
             yystack.pop ();
@@ -693,7 +804,11 @@ b4_dollar_popdef])[]dnl
               yystack.print (yyDebugStream);
           }
 
-        ]b4_locations_if([
+        if (label == YYABORT)
+            /* Leave the switch.  */
+            break;
+
+]b4_locations_if([
         /* Muck with the stack to setup for yylloc.  */
         yystack.push (0, null, yylloc);
         yystack.push (0, null, yyerrloc);
@@ -711,13 +826,91 @@ b4_dollar_popdef])[]dnl
 
         /* Accept.  */
       case YYACCEPT:
-        return true;
+        ]b4_push_if([this.push_parse_initialized = false; return YYACCEPT;],
+                    [return true;])[
 
         /* Abort.  */
       case YYABORT:
-        return false;
+        ]b4_push_if([this.push_parse_initialized = false; return YYABORT;],
+                    [return false;])[
       }
+}
+]b4_push_if([[
+  boolean push_parse_initialized = false;
+
+    /**
+     * (Re-)Initialize the state of the push parser.
+     */
+  public void push_parse_initialize()
+  {
+    /* Lookahead and lookahead in internal form.  */
+    this.yychar = yyempty_;
+    this.yytoken = 0;
+
+    /* State.  */
+    this.yyn = 0;
+    this.yylen = 0;
+    this.yystate = 0;
+    this.yystack = new YYStack ();
+    this.label = YYNEWSTATE;
+
+    /* Error handling.  */
+    this.yynerrs_ = 0;
+    ]b4_locations_if([/* The location where the error started.  */
+    this.yyerrloc = null;
+    this.yylloc = new b4_location_type (null, null);])[
+
+    /* Semantic value of the lookahead.  */
+    this.yylval = null;
+
+    yystack.push (this.yystate, this.yylval]b4_locations_if([, this.yylloc])[);
+
+    this.push_parse_initialized = true;
+
   }
+]b4_locations_if([
+  /**
+   * Push parse given input from an external lexer.
+   *
+   * @@param yylextoken current token
+   * @@param yylexval current lval
+   * @@param yyylexpos current position
+   *
+   * @@return <tt>YYACCEPT, YYABORT, YYPUSH_MORE</tt>
+   */
+  public int push_parse (int yylextoken, b4_yystype yylexval, b4_position_type yylexpos)
+      b4_maybe_throws([b4_list2([b4_lex_throws], [b4_throws])])
+  {
+    return push_parse (yylextoken, yylexval, new b4_location_type (yylexpos));
+  }
+])[]])
+
+b4_both_if([[
+  /**
+   * Parse input from the scanner that was specified at object construction
+   * time.  Return whether the end of the input was reached successfully.
+   * This version of parse () is defined only when api.push-push=both.
+   *
+   * @@return <tt>true</tt> if the parsing succeeds.  Note that this does not
+   *          imply that there were no syntax errors.
+   */
+   public boolean parse () ]b4_maybe_throws([b4_list2([b4_lex_throws], [b4_throws])])[
+   {
+      if (yylexer == null)
+        throw new NullPointerException("Null Lexer");
+      int status;
+      do {
+        int token = yylexer.yylex();
+        ]b4_yystype[ lval = yylexer.getLVal();
+]b4_locations_if([dnl
+        b4_location_type yyloc = new b4_location_type (yylexer.getStartPos (),
+                                              yylexer.getEndPos ());])[
+        ]b4_locations_if([status = push_parse(token,lval,yyloc);],[
+        status = push_parse(token,lval);])[
+      } while (status == YYPUSH_MORE);
+      return (status == YYACCEPT);
+  }
+]])[
 
   // Generate an error message.
   private String yysyntax_error (int yystate, int tok)
@@ -752,8 +945,8 @@ b4_dollar_popdef])[]dnl
         */
         if (tok != yyempty_)
           {
-            // FIXME: This method of building the message is not compatible
-            // with internationalization.
+            /* FIXME: This method of building the message is not compatible
+               with internationalization.  */
             StringBuffer res =
               new StringBuffer ("syntax error, unexpected ");
             res.append (yytnamerr_ (yytname_[tok]));
@@ -802,8 +995,9 @@ b4_dollar_popdef])[]dnl
   }
 
   /**
-   * Whether the given <code>yytable_</code> value indicates a syntax error.
-   * @@param yyvalue   the value to check
+   * Whether the given <code>yytable_</code>
+   * value indicates a syntax error.
+   * @@param yyvalue the value to check
    */
   private static boolean yy_table_value_is_error_ (int yyvalue)
   {
@@ -825,6 +1019,7 @@ b4_dollar_popdef])[]dnl
   ]b4_integral_parser_table_define([rline], [b4_rline],
   [[YYRLINE[YYN] -- Source line where rule number YYN was defined.]])[
 
+
   // Report on the debug stream that the rule yyrule is going to be reduced.
   private void yy_reduce_print (int yyrule, YYStack yystack)
   {

data/location.cc

@@ -25,10 +25,9 @@ m4_define([b4_position_define],
 [[  /// Abstract a position.
   class position
   {
-  public:
-]m4_ifdef([b4_location_constructors], [[
+  public:]m4_ifdef([b4_location_constructors], [[
     /// Construct a position.
-    explicit position (]b4_percent_define_get([[filename_type]])[* f = YY_NULL,
+    explicit position (]b4_percent_define_get([[filename_type]])[* f = YY_NULLPTR,
                        unsigned int l = ]b4_location_initial_line[u,
                        unsigned int c = ]b4_location_initial_column[u)
       : filename (f)
@@ -39,7 +38,7 @@ m4_define([b4_position_define],
 
 ]])[
     /// Initialization.
-    void initialize (]b4_percent_define_get([[filename_type]])[* fn = YY_NULL,
+    void initialize (]b4_percent_define_get([[filename_type]])[* fn = YY_NULLPTR,
                      unsigned int l = ]b4_location_initial_line[u,
                      unsigned int c = ]b4_location_initial_column[u)
     {
@@ -53,14 +52,17 @@ m4_define([b4_position_define],
     /// (line related) Advance to the COUNT next lines.
     void lines (int count = 1)
     {
-      column = ]b4_location_initial_column[u;
-      line += count;
+      if (count)
+        {
+          column = ]b4_location_initial_column[u;
+          line = add_ (line, count, ]b4_location_initial_line[);
+        }
     }
 
     /// (column related) Advance to the COUNT next columns.
     void columns (int count = 1)
     {
-      column = std::max (]b4_location_initial_column[u, column + count);
+      column = add_ (column, count, ]b4_location_initial_column[);
     }
     /** \} */
 
@@ -70,36 +72,44 @@ m4_define([b4_position_define],
     unsigned int line;
     /// Current column number.
     unsigned int column;
+
+  private:
+    /// Compute max(min, lhs+rhs) (provided min <= lhs).
+    static unsigned int add_ (unsigned int lhs, int rhs, unsigned int min)
+    {
+      return (0 < rhs || -static_cast<unsigned int>(rhs) < lhs
+              ? rhs + lhs
+              : min);
+    }
   };
 
   /// Add and assign a position.
   inline position&
-  operator+= (position& res, const int width)
+  operator+= (position& res, int width)
   {
     res.columns (width);
     return res;
   }
 
   /// Add two position objects.
-  inline const position
-  operator+ (const position& begin, const int width)
+  inline position
+  operator+ (position res, int width)
   {
-    position res = begin;
     return res += width;
   }
 
   /// Add and assign a position.
   inline position&
-  operator-= (position& res, const int width)
+  operator-= (position& res, int width)
   {
     return res += -width;
   }
 
   /// Add two position objects.
-  inline const position
-  operator- (const position& begin, const int width)
+  inline position
+  operator- (position res, int width)
   {
-    return begin + -width;
+    return res -= width;
   }
 ]b4_percent_define_flag_if([[define_location_comparison]], [[
   /// Compare two position objects.
@@ -168,7 +178,7 @@ m4_define([b4_location_define],
 
 ])[
     /// Initialization.
-    void initialize (]b4_percent_define_get([[filename_type]])[* f = YY_NULL,
+    void initialize (]b4_percent_define_get([[filename_type]])[* f = YY_NULLPTR,
                      unsigned int l = ]b4_location_initial_line[u,
                      unsigned int c = ]b4_location_initial_column[u)
     {
@@ -186,13 +196,13 @@ m4_define([b4_location_define],
     }
 
     /// Extend the current location to the COUNT next columns.
-    void columns (unsigned int count = 1)
+    void columns (int count = 1)
     {
       end += count;
     }
 
     /// Extend the current location to the COUNT next lines.
-    void lines (unsigned int count = 1)
+    void lines (int count = 1)
     {
       end.lines (count);
     }
@@ -207,26 +217,35 @@ m4_define([b4_location_define],
   };
 
   /// Join two location objects to create a location.
-  inline const location operator+ (const location& begin, const location& end)
+  inline location operator+ (location res, const location& end)
   {
-    location res = begin;
     res.end = end.end;
     return res;
   }
 
-  /// Add two location objects.
-  inline const location operator+ (const location& begin, unsigned int width)
+  /// Change end position in place.
+  inline location& operator+= (location& res, int width)
   {
-    location res = begin;
     res.columns (width);
     return res;
   }
 
-  /// Add and assign a location.
-  inline location& operator+= (location& res, unsigned int width)
+  /// Change end position.
+  inline location operator+ (location res, int width)
   {
-    res.columns (width);
-    return res;
+    return res += width;
+  }
+
+  /// Change end position in place.
+  inline location& operator-= (location& res, int width)
+  {
+    return res += -width;
+  }
+
+  /// Change end position.
+  inline location operator- (const location& begin, int width)
+  {
+    return begin + -width;
   }
 ]b4_percent_define_flag_if([[define_location_comparison]], [[
   /// Compare two location objects.

data/stack.hh

@@ -72,6 +72,12 @@ m4_define([b4_stack_define],
         seq_.pop_back ();
     }
 
+    void
+    clear ()
+    {
+      seq_.clear ();
+    }
+
     inline
     typename S::size_type
     size () const
@@ -94,6 +100,8 @@ m4_define([b4_stack_define],
     }
 
   private:
+    stack (const stack&);
+    stack& operator= (const stack&);
     /// The wrapped container.
     S seq_;
   };

data/variant.hh

@@ -26,7 +26,7 @@
 # YYTYPE.
 m4_define([b4_symbol_variant],
 [m4_pushdef([b4_dollar_dollar],
-            [$2.$3< $][3 >(m4_shift3($@))])dnl
+            [$2.$3< $][3 > (m4_shift3($@))])dnl
   switch ($1)
     {
 b4_type_foreach([b4_type_action_])[]dnl
@@ -63,7 +63,7 @@ m4_define([b4_char_sizeof],
 [b4_symbol_if([$1], [has_type],
 [
 m4_map([      b4_symbol_tag_comment], [$@])dnl
-      char _b4_char_sizeof_dummy@{sizeof([b4_symbol([$1], [type])])@};
+      char _b4_char_sizeof_dummy@{sizeof(b4_symbol([$1], [type]))@};
 ])])
 
 
@@ -95,22 +95,22 @@ m4_define([b4_variant_define],
 
     /// Empty construction.
     variant ()]b4_parse_assert_if([
-      : tname (YY_NULL)])[
+      : yytname_ (YY_NULLPTR)])[
     {}
 
     /// Construct and fill.
     template <typename T>
     variant (const T& t)]b4_parse_assert_if([
-      : tname (typeid (T).name ())])[
+      : yytname_ (typeid (T).name ())])[
     {
       YYASSERT (sizeof (T) <= S);
-      new (buffer.raw) T (t);
+      new (yyas_<T> ()) T (t);
     }
 
     /// Destruction, allowed only if empty.
     ~variant ()
     {]b4_parse_assert_if([
-      YYASSERT (!tname);
+      YYASSERT (!yytname_);
     ])[}
 
     /// Instantiate an empty \a T in here.
@@ -118,10 +118,10 @@ m4_define([b4_variant_define],
     T&
     build ()
     {]b4_parse_assert_if([
-      YYASSERT (!tname);
+      YYASSERT (!yytname_);
       YYASSERT (sizeof (T) <= S);
-      tname = typeid (T).name ();])[
-      return *new (buffer.raw) T;
+      yytname_ = typeid (T).name ();])[
+      return *new (yyas_<T> ()) T;
     }
 
     /// Instantiate a \a T in here from \a t.
@@ -129,10 +129,10 @@ m4_define([b4_variant_define],
     T&
     build (const T& t)
     {]b4_parse_assert_if([
-      YYASSERT (!tname);
+      YYASSERT (!yytname_);
       YYASSERT (sizeof (T) <= S);
-      tname = typeid (T).name ();])[
-      return *new (buffer.raw) T (t);
+      yytname_ = typeid (T).name ();])[
+      return *new (yyas_<T> ()) T (t);
     }
 
     /// Accessor to a built \a T.
@@ -140,9 +140,9 @@ m4_define([b4_variant_define],
     T&
     as ()
     {]b4_parse_assert_if([
-      YYASSERT (tname == typeid (T).name ());
+      YYASSERT (yytname_ == typeid (T).name ());
       YYASSERT (sizeof (T) <= S);])[
-      return reinterpret_cast<T&> (buffer.raw);
+      return *yyas_<T> ();
     }
 
     /// Const accessor to a built \a T (for %printer).
@@ -150,9 +150,9 @@ m4_define([b4_variant_define],
     const T&
     as () const
     {]b4_parse_assert_if([
-      YYASSERT (tname == typeid (T).name ());
+      YYASSERT (yytname_ == typeid (T).name ());
       YYASSERT (sizeof (T) <= S);])[
-      return reinterpret_cast<const T&> (buffer.raw);
+      return *yyas_<T> ();
     }
 
     /// Swap the content with \a other, of same type.
@@ -167,9 +167,9 @@ m4_define([b4_variant_define],
     void
     swap (self_type& other)
     {]b4_parse_assert_if([
-      YYASSERT (tname);
-      YYASSERT (tname == other.tname);])[
-      std::swap (as<T>(), other.as<T>());
+      YYASSERT (yytname_);
+      YYASSERT (yytname_ == other.yytname_);])[
+      std::swap (as<T> (), other.as<T> ());
     }
 
     /// Move the content of \a other to this.
@@ -178,11 +178,10 @@ m4_define([b4_variant_define],
     template <typename T>
     void
     move (self_type& other)
-    {]b4_parse_assert_if([
-      YYASSERT (!tname);])[
-      build<T>();
-      swap<T>(other);
-      other.destroy<T>();
+    {
+      build<T> ();
+      swap<T> (other);
+      other.destroy<T> ();
     }
 
     /// Copy the content of \a other to this.
@@ -199,7 +198,7 @@ m4_define([b4_variant_define],
     destroy ()
     {
       as<T> ().~T ();]b4_parse_assert_if([
-      tname = YY_NULL;])[
+      yytname_ = YY_NULLPTR;])[
     }
 
   private:
@@ -207,17 +206,34 @@ m4_define([b4_variant_define],
     self_type& operator=(const self_type&);
     variant (const self_type&);
 
-    /// A buffer large enough to store any of the semantic values.
-    /// Long double is chosen as it has the strongest alignment
-    /// constraints.
+    /// Accessor to raw memory as \a T.
+    template <typename T>
+    T*
+    yyas_ ()
+    {
+      void *yyp = yybuffer_.yyraw;
+      return static_cast<T*> (yyp);
+     }
+
+    /// Const accessor to raw memory as \a T.
+    template <typename T>
+    const T*
+    yyas_ () const
+    {
+      const void *yyp = yybuffer_.yyraw;
+      return static_cast<const T*> (yyp);
+     }
+
     union
     {
-      long double align_me;
-      char raw[S];
-    } buffer;]b4_parse_assert_if([
+      /// Strongest alignment constraints.
+      long double yyalign_me;
+      /// A buffer large enough to store any of the semantic values.
+      char yyraw[S];
+    } yybuffer_;]b4_parse_assert_if([
 
     /// Whether the content is built: if defined, the name of the stored type.
-    const char* tname;])[
+    const char *yytname_;])[
   };
 ]])
 
@@ -227,16 +243,16 @@ m4_define([b4_variant_define],
 ## -------------------------- ##
 
 
-# b4_semantic_type_declare
-# ------------------------
+# b4_value_type_declare
+# ---------------------
 # Declare semantic_type.
-m4_define([b4_semantic_type_declare],
-[    /// An auxiliary type to compute the largest semantic type.
+m4_define([b4_value_type_declare],
+[[    /// An auxiliary type to compute the largest semantic type.
     union union_type
     {]b4_type_foreach([b4_char_sizeof])[};
 
     /// Symbol semantic values.
-    typedef variant<sizeof(union_type)> semantic_type;dnl
+    typedef variant<sizeof(union_type)> semantic_type;][]dnl
 ])
 
 
@@ -246,7 +262,7 @@ m4_define([b4_semantic_type_declare],
 # ----------------------------
 m4_define([b4_symbol_value],
 [m4_ifval([$2],
-          [$1.as< $2 >()],
+          [$1.as< $2 > ()],
           [$1])])
 
 # b4_symbol_value_template(VAL, [TYPE])
@@ -254,7 +270,7 @@ m4_define([b4_symbol_value],
 # Same as b4_symbol_value, but used in a template method.
 m4_define([b4_symbol_value_template],
 [m4_ifval([$2],
-          [$1.template as< $2 >()],
+          [$1.template as< $2 > ()],
           [$1])])
 
 
@@ -304,14 +320,13 @@ b4_join(b4_symbol_if([$1], [has_type],
     return symbol_type (b4_join([token::b4_symbol([$1], [id])],
                                 b4_symbol_if([$1], [has_type], [v]),
                                 b4_locations_if([l])));
-
   }
 
 ])])])
 
 
 # b4_basic_symbol_constructor_declare
-# ----------------------------------
+# -----------------------------------
 # Generate a constructor declaration for basic_symbol from given type.
 m4_define([b4_basic_symbol_constructor_declare],
 [[

data/xslt/xml2dot.xsl

@@ -201,6 +201,8 @@
   <xsl:if test="$point = 0">
     <xsl:text> .</xsl:text>
   </xsl:if>
+
+  <!-- RHS -->
   <xsl:for-each select="rhs/symbol|rhs/empty">
     <xsl:apply-templates select="."/>
     <xsl:if test="$point = position()">
@@ -214,7 +216,9 @@
   <xsl:value-of select="."/>
 </xsl:template>
 
-<xsl:template match="empty"/>
+<xsl:template match="empty">
+  <xsl:text> %empty</xsl:text>
+</xsl:template>
 
 <xsl:template match="lookaheads">
   <xsl:text>  [</xsl:text>

data/xslt/xml2text.xsl

@@ -350,12 +350,7 @@
     <xsl:if test="position() = $point + 1">
       <xsl:text> .</xsl:text>
     </xsl:if>
-    <xsl:if test="$itemset = 'true' and name(.) != 'empty'">
-      <xsl:apply-templates select="."/>
-    </xsl:if>
-    <xsl:if test="$itemset != 'true'">
-      <xsl:apply-templates select="."/>
-    </xsl:if>
+    <xsl:apply-templates select="."/>
     <xsl:if test="position() = last() and position() = $point">
       <xsl:text> .</xsl:text>
     </xsl:if>
@@ -373,7 +368,7 @@
 </xsl:template>
 
 <xsl:template match="empty">
-  <xsl:text> /* empty */</xsl:text>
+  <xsl:text> %empty</xsl:text>
 </xsl:template>
 
 <xsl:template match="lookaheads">

data/xslt/xml2xhtml.xsl

@@ -532,12 +532,7 @@
       <xsl:text> </xsl:text>
       <span class="point">.</span>
     </xsl:if>
-    <xsl:if test="$itemset = 'true' and name(.) != 'empty'">
-      <xsl:apply-templates select="."/>
-    </xsl:if>
-    <xsl:if test="$itemset != 'true'">
-      <xsl:apply-templates select="."/>
-    </xsl:if>
+    <xsl:apply-templates select="."/>
     <xsl:if test="position() = last() and position() = $point">
       <xsl:text> </xsl:text>
       <span class="point">.</span>
@@ -563,7 +558,7 @@
 </xsl:template>
 
 <xsl:template match="empty">
-  <xsl:text> &#949;</xsl:text>
+  <xsl:text> %empty</xsl:text>
 </xsl:template>
 
 <xsl:template match="lookaheads">

data/yacc.c

@@ -143,7 +143,6 @@ m4_define([b4_rhs_value],
           [b4_symbol_value([yyvsp@{b4_subtract([$2], [$1])@}], [$3])])
 
 
-
 ## ----------- ##
 ## Locations.  ##
 ## ----------- ##
@@ -176,36 +175,19 @@ m4_define([b4_declare_scanner_communication_variables], [[
 int yychar;
 
 ]b4_pure_if([[
-#if defined __GNUC__ && 407 <= __GNUC__ * 100 + __GNUC_MINOR__
-/* Suppress an incorrect diagnostic about yylval being uninitialized.  */
-# define YY_IGNORE_MAYBE_UNINITIALIZED_BEGIN \
-    _Pragma ("GCC diagnostic push") \
-    _Pragma ("GCC diagnostic ignored \"-Wuninitialized\"")\
-    _Pragma ("GCC diagnostic ignored \"-Wmaybe-uninitialized\"")
-# define YY_IGNORE_MAYBE_UNINITIALIZED_END \
-    _Pragma ("GCC diagnostic pop")
-#else
+/* The semantic value of the lookahead symbol.  */
 /* Default value used for initialization, for pacifying older GCCs
    or non-GCC compilers.  */
-static YYSTYPE yyval_default;
-# define YY_INITIAL_VALUE(Value) = Value
-#endif]b4_locations_if([[
-static YYLTYPE yyloc_default][]b4_yyloc_default[;]])])[
-#ifndef YY_IGNORE_MAYBE_UNINITIALIZED_BEGIN
-# define YY_IGNORE_MAYBE_UNINITIALIZED_BEGIN
-# define YY_IGNORE_MAYBE_UNINITIALIZED_END
-#endif
-#ifndef YY_INITIAL_VALUE
-# define YY_INITIAL_VALUE(Value) /* Nothing. */
-#endif
-
-/* The semantic value of the lookahead symbol.  */
-YYSTYPE yylval YY_INITIAL_VALUE(yyval_default);]b4_locations_if([[
+YY_INITIAL_VALUE (static YYSTYPE yyval_default;)
+YYSTYPE yylval YY_INITIAL_VALUE (= yyval_default);]b4_locations_if([[
 
 /* Location data for the lookahead symbol.  */
-YYLTYPE yylloc]b4_pure_if([ = yyloc_default], [b4_yyloc_default])[;
-]])b4_pure_if([], [[
-
+static YYLTYPE yyloc_default]b4_yyloc_default[;
+YYLTYPE yylloc = yyloc_default;]])],
+[[/* The semantic value of the lookahead symbol.  */
+YYSTYPE yylval;]b4_locations_if([[
+/* Location data for the lookahead symbol.  */
+YYLTYPE yylloc]b4_yyloc_default[;]])[
 /* Number of syntax errors so far.  */
 int yynerrs;]])])
 
@@ -223,9 +205,9 @@ m4_define([b4_declare_parser_state_variables], [b4_pure_if([[
     int yyerrstatus;
 
     /* The stacks and their tools:
-       `yyss': related to states.
-       `yyvs': related to semantic values.]b4_locations_if([[
-       `yyls': related to locations.]])[
+       'yyss': related to states.
+       'yyvs': related to semantic values.]b4_locations_if([[
+       'yyls': related to locations.]])[
 
        Refer to the stacks through separate pointers, to allow yyoverflow
        to reallocate them elsewhere.  */
@@ -431,12 +413,7 @@ typedef short int yytype_int16;
 # endif
 #endif
 
-/* Suppress unused-variable warnings by "using" E.  */
-#ifdef __GNUC__
-# define YYUSE(E) ((void) (E))
-#else
-# define YYUSE(E) /* empty */
-#endif
+]b4_attribute_define[
 
 #if ]b4_lac_if([[1]], [[! defined yyoverflow || YYERROR_VERBOSE]])[
 
@@ -468,7 +445,7 @@ b4_push_if([], [b4_lac_if([], [[
 # endif]])])[
 
 # ifdef YYSTACK_ALLOC
-   /* Pacify GCC's `empty if-body' warning.  */
+   /* Pacify GCC's 'empty if-body' warning.  */
 #  define YYSTACK_FREE(Ptr) do { /* empty */; } while (0)
 #  ifndef YYSTACK_ALLOC_MAXIMUM
     /* The OS might guarantee only one guard page at the bottom of the stack,
@@ -1131,11 +1108,11 @@ yysyntax_error (YYSIZE_T *yymsg_alloc, char **yymsg,
                 ]b4_lac_if([[yytype_int16 *yyesa, yytype_int16 **yyes,
                 YYSIZE_T *yyes_capacity, ]])[yytype_int16 *yyssp, int yytoken)
 {
-  YYSIZE_T yysize0 = yytnamerr (YY_NULL, yytname[yytoken]);
+  YYSIZE_T yysize0 = yytnamerr (YY_NULLPTR, yytname[yytoken]);
   YYSIZE_T yysize = yysize0;
   enum { YYERROR_VERBOSE_ARGS_MAXIMUM = 5 };
   /* Internationalized format string. */
-  const char *yyformat = YY_NULL;
+  const char *yyformat = YY_NULLPTR;
   /* Arguments of yyformat. */
   char const *yyarg[YYERROR_VERBOSE_ARGS_MAXIMUM];
   /* Number of reported tokens (one for the "unexpected", one per
@@ -1210,7 +1187,7 @@ yysyntax_error (YYSIZE_T *yymsg_alloc, char **yymsg,
                   }
                 yyarg[yycount++] = yytname[yyx];
                 {
-                  YYSIZE_T yysize1 = yysize + yytnamerr (YY_NULL, yytname[yyx]);
+                  YYSIZE_T yysize1 = yysize + yytnamerr (YY_NULLPTR, yytname[yyx]);
                   if (! (yysize <= yysize1
                          && yysize1 <= YYSTACK_ALLOC_MAXIMUM))
                     return 2;
@@ -1294,7 +1271,7 @@ static char yypstate_allocated = 0;]])b4_pull_if([
 
 b4_function_define([[yyparse]], [[int]], b4_parse_param)[
 {
-  return yypull_parse (YY_NULL]m4_ifset([b4_parse_param],
+  return yypull_parse (YY_NULLPTR]m4_ifset([b4_parse_param],
                                   [[, ]b4_args(b4_parse_param)])[);
 }
 
@@ -1336,10 +1313,10 @@ b4_function_define([[yyparse]], [[int]], b4_parse_param)[
 {
   yypstate *yyps;]b4_pure_if([], [[
   if (yypstate_allocated)
-    return YY_NULL;]])[
+    return YY_NULLPTR;]])[
   yyps = (yypstate *) malloc (sizeof *yyps);
   if (!yyps)
-    return YY_NULL;
+    return YY_NULLPTR;
   yyps->yynew = 1;]b4_pure_if([], [[
   yypstate_allocated = 1;]])[
   return yyps;
@@ -1654,7 +1631,7 @@ yyreduce:
   yylen = yyr2[yyn];
 
   /* If YYLEN is nonzero, implement the default value of the action:
-     `$$ = $1'.
+     '$$ = $1'.
 
      Otherwise, the following line sets YYVAL to garbage.
      This behavior is undocumented and Bison
@@ -1702,7 +1679,7 @@ yyreduce:
   *++yyvsp = yyval;]b4_locations_if([
   *++yylsp = yyloc;])[
 
-  /* Now `shift' the result of the reduction.  Determine what state
+  /* Now 'shift' the result of the reduction.  Determine what state
      that goes to, based on the state we popped back to and the rule
      number reduced by.  */
 

doc/figs/example.txt

@@ -0,0 +1,2 @@
+This file is a stub, not used by the documentation.  If you feel like
+contributing ASCII art for example.gv, please step forward!

doc/local.mk

@@ -23,9 +23,10 @@ doc_bison_TEXINFOS =                            \
 # Cannot express dependencies directly on file names because of Automake.
 # Obfuscate with a variable.
 doc_bison = doc/bison
-$(doc_bison).dvi: $(FIGS_DOT:.dot=.eps)
-$(doc_bison).pdf: $(FIGS_DOT:.dot=.pdf)
-$(doc_bison).html: $(FIGS_DOT:.dot=.png)
+$(doc_bison).dvi: $(FIGS_GV:.gv=.eps)
+$(doc_bison).info: $(FIGS_GV:.gv=.txt)
+$(doc_bison).pdf: $(FIGS_GV:.gv=.pdf)
+$(doc_bison).html: $(FIGS_GV:.gv=.png)
 
 TEXI2DVI = texi2dvi --build-dir=doc/bison.t2d -I doc
 CLEANDIRS = doc/bison.t2d
@@ -37,7 +38,7 @@ MOSTLYCLEANFILES += $(top_srcdir)/doc/*.t
 CROSS_OPTIONS_PL = $(top_srcdir)/build-aux/cross-options.pl
 CROSS_OPTIONS_TEXI = $(top_srcdir)/doc/cross-options.texi
 $(CROSS_OPTIONS_TEXI): doc/bison.help $(CROSS_OPTIONS_PL)
-# Create $@~ which is the previous contents.  Don't use `mv' here so
+# Create $@~ which is the previous contents.  Don't use 'mv' here so
 # that even if we are interrupted, the file is still available for
 # diff in the next run.  Note that $@ might not exist yet.
 	$(AM_V_GEN){ test ! -f $@ || cat $@; } >$@~
@@ -117,32 +118,34 @@ $(top_srcdir)/doc/bison.1: doc/bison.help doc/bison.x $(top_srcdir)/configure
 	fi
 	$(AM_V_at)rm -f $@*.t
 
+if ENABLE_YACC
 nodist_man_MANS = doc/yacc.1
+endif
 
 ## ----------------------------- ##
 ## Graphviz examples generation. ##
 ## ----------------------------- ##
 
 CLEANDIRS += doc/figs
-FIGS_DOT =                                                      \
-  doc/figs/example.dot                                          \
-  doc/figs/example-reduce.dot doc/figs/example-shift.dot
-EXTRA_DIST +=                                                           \
-  $(FIGS_DOT)                                                           \
-  $(FIGS_DOT:.dot=.eps) $(FIGS_DOT:.dot=.pdf) $(FIGS_DOT:.dot=.png)
-SUFFIXES += .dot .eps .pdf .png
+FIGS_GV =                                               \
+  doc/figs/example.gv                                   \
+  doc/figs/example-reduce.gv doc/figs/example-shift.gv
+EXTRA_DIST +=                                                   \
+  $(FIGS_GV) $(FIGS_GV:.gv=.txt)                                \
+  $(FIGS_GV:.gv=.eps) $(FIGS_GV:.gv=.pdf) $(FIGS_GV:.gv=.png)
+SUFFIXES += .gv .eps .pdf .png
 
-.dot.eps:
+.gv.eps:
 	$(AM_V_GEN) $(MKDIR_P) `echo "./$@" | sed -e 's,/[^/]*$$,,'`
 	$(AM_V_at) $(DOT) -Gmargin=0 -Teps $< >$@.tmp
 	$(AM_V_at) mv $@.tmp $@
 
-.dot.pdf:
+.gv.pdf:
 	$(AM_V_GEN) $(MKDIR_P) `echo "./$@" | sed -e 's,/[^/]*$$,,'`
 	$(AM_V_at) $(DOT) -Gmargin=0 -Tpdf $< >$@.tmp
 	$(AM_V_at) mv $@.tmp $@
 
-.dot.png:
+.gv.png:
 	$(AM_V_GEN) $(MKDIR_P) `echo "./$@" | sed -e 's,/[^/]*$$,,'`
 	$(AM_V_at) $(DOT) -Gmargin=0 -Tpng $< >$@.tmp
 	$(AM_V_at) mv $@.tmp $@

etc/bench.pl.in

@@ -204,9 +204,9 @@ Format the list of directives for Bison for bench named C<$bench>.
 sub directives($@)
 {
   my ($bench, @directive) = @_;
-  my $res = "/* Directives for bench `$bench'. */\n";
+  my $res = "/* Directives for bench '$bench'. */\n";
   $res .= join ("\n", @directive) . "\n";
-  $res .= "/* End of directives for bench `$bench'. */\n";
+  $res .= "/* End of directives for bench '$bench'. */\n";
   return $res;
 }
 

examples/calc++/local.mk

@@ -19,7 +19,7 @@
 
 # Don't depend on $(BISON) otherwise we would rebuild these files
 # in srcdir, including during distcheck, which is forbidden.
-examples/calc++/calc++-parser.stamp: $(BISON_IN)
+%D%/calc++-parser.stamp: $(BISON_IN)
 SUFFIXES += .yy .stamp
 .yy.stamp:
 	$(AM_V_YACC)rm -f $@
@@ -27,14 +27,14 @@ SUFFIXES += .yy .stamp
 	$(AM_V_at)$(YACCCOMPILE) -o $*.cc $<
 	$(AM_V_at)mv -f $@.tmp $@
 
-$(calc_sources_generated): examples/calc++/calc++-parser.stamp
-	@test -f $@ || rm -f examples/calc++/calc++-parser.stamp
-	@test -f $@ || $(MAKE) $(AM_MAKEFLAGS) examples/calc++/calc++-parser.stamp
+$(calc_sources_generated): %D%/calc++-parser.stamp
+	@test -f $@ || rm -f %D%/calc++-parser.stamp
+	@test -f $@ || $(MAKE) $(AM_MAKEFLAGS) %D%/calc++-parser.stamp
 CLEANFILES +=                                   \
   $(calc_sources_generated)                     \
-  examples/calc++/calc++-parser.output          \
-  examples/calc++/calc++-parser.stamp           \
-  examples/calc++/calc++-scanner.cc
+  %D%/calc++-parser.output                      \
+  %D%/calc++-parser.stamp                       \
+  %D%/calc++-scanner.cc
 
 
 ## -------------------- ##
@@ -42,34 +42,35 @@ CLEANFILES +=                                   \
 ## -------------------- ##
 
 # Avoid using BUILT_SOURCES which is too global.
-$(examples_calc___calc___OBJECTS): $(calc_sources_generated)
+$(%C%_calc___OBJECTS): $(calc_sources_generated)
 
-calc_sources_extracted =			\
-  examples/calc++/calc++-driver.cc		\
-  examples/calc++/calc++-driver.hh		\
-  examples/calc++/calc++-scanner.ll		\
-  examples/calc++/calc++.cc
-calc_extracted =				\
-  $(calc_sources_extracted)			\
-  examples/calc++/calc++-parser.yy
+calc_sources_extracted =                        \
+  %D%/calc++-driver.cc                          \
+  %D%/calc++-driver.hh                          \
+  %D%/calc++-scanner.ll                         \
+  %D%/calc++.cc
+calc_extracted =                                \
+  $(calc_sources_extracted)                     \
+  %D%/calc++-parser.yy
 extracted += $(calc_extracted)
-calc_sources_generated =			\
-  examples/calc++/calc++-parser.cc		\
-  examples/calc++/calc++-parser.hh		\
-  examples/calc++/location.hh			\
-  examples/calc++/position.hh			\
-  examples/calc++/stack.hh
-calc_sources =					\
-  $(calc_sources_extracted)			\
+calc_sources_generated =                        \
+  %D%/calc++-parser.cc                          \
+  %D%/calc++-parser.hh                          \
+  %D%/location.hh                               \
+  %D%/position.hh                               \
+  %D%/stack.hh
+calc_sources =                                  \
+  $(calc_sources_extracted)                     \
   $(calc_sources_generated)
 
-if BISON_CXX_WORKS
-check_PROGRAMS += examples/calc++/calc++
-nodist_examples_calc___calc___SOURCES =		\
+if FLEX_CXX_WORKS
+check_PROGRAMS += %D%/calc++
+nodist_%C%_calc___SOURCES =                     \
   $(calc_sources)
 
-examples_calc___calc___CPPFLAGS = -I$(top_builddir)/examples/calc++
-examples_calc___calc___CXXFLAGS =			\
-  $(AM_CXXFLAGS) $(WARN_NO_NULL_CONVERSION_CXXFLAGS)
-dist_TESTS += examples/calc++/calc++.test
+%C%_calc___CPPFLAGS = -I$(top_builddir)/%D%
+%C%_calc___CXXFLAGS = $(AM_CXXFLAGS) $(FLEX_SCANNER_CXXFLAGS)
+dist_TESTS += %D%/calc++.test
+else
+EXTRA_DIST += %D%/calc++.test
 endif

examples/local.mk

@@ -13,11 +13,10 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-dist_noinst_SCRIPTS = examples/extexi examples/test
-TEST_LOG_COMPILER = $(top_srcdir)/examples/test
+dist_noinst_SCRIPTS = %D%/extexi %D%/test
+TEST_LOG_COMPILER = $(top_srcdir)/%D%/test
 
 AM_CXXFLAGS =							\
-  $(NO_STRICT_ALIAS_CXXFLAGS)					\
   $(WARN_CXXFLAGS) $(WARN_CXXFLAGS_TEST) $(WERROR_CXXFLAGS)
 
 ## ------------ ##
@@ -25,20 +24,20 @@ AM_CXXFLAGS =							\
 ## ------------ ##
 
 doc = $(top_srcdir)/doc/bison.texi
-extexi = $(top_srcdir)/examples/extexi
-extract = VERSION="$(VERSION)" $(PERL) -f $(extexi) $(doc) --
+extexi = $(top_srcdir)/%D%/extexi
+extract = VERSION="$(VERSION)" $(PERL) $(extexi) $(doc) --
 extracted =
-CLEANFILES += $(extracted) examples/extracted.stamp
-examples/extracted.stamp: $(doc) $(extexi)
+CLEANFILES += $(extracted) %D%/extracted.stamp
+%D%/extracted.stamp: $(doc) $(extexi)
 	$(AM_V_GEN)rm -f $@ $@.tmp
 	$(AM_V_at)touch $@.tmp
 	$(AM_V_at)$(extract) $(extracted)
 	$(AM_V_at)mv $@.tmp $@
 
-$(extracted): examples/extracted.stamp
-	@test -f $@ || rm -f examples/extracted.stamp
-	@test -f $@ || $(MAKE) $(AM_MAKEFLAGS) examples/extracted.stamp
+$(extracted): %D%/extracted.stamp
+	@test -f $@ || rm -f %D%/extracted.stamp
+	@test -f $@ || $(MAKE) $(AM_MAKEFLAGS) %D%/extracted.stamp
 
-include examples/calc++/local.mk
-include examples/mfcalc/local.mk
-include examples/rpcalc/local.mk
+include %D%/calc++/local.mk
+include %D%/mfcalc/local.mk
+include %D%/rpcalc/local.mk

examples/mfcalc/local.mk

@@ -18,19 +18,15 @@
 ## -------------------- ##
 
 BUILT_SOURCES += $(mfcalc_sources)
-CLEANFILES +=  examples/mfcalc/mfcalc.[ch] examples/mfcalc/mfcalc.output
+CLEANFILES +=  %D%/mfcalc.[ch] %D%/mfcalc.output
 
-mfcalc_extracted =				\
-  examples/mfcalc/calc.h			\
-  examples/mfcalc/mfcalc.y
-mfcalc_sources =				\
-  $(mfcalc_extracted)
+mfcalc_extracted = %D%/calc.h %D%/mfcalc.y
+mfcalc_sources = $(mfcalc_extracted)
 extracted += $(mfcalc_extracted)
 
-check_PROGRAMS += examples/mfcalc/mfcalc
-examples_mfcalc_mfcalc_LDADD = -lm
-nodist_examples_mfcalc_mfcalc_SOURCES =		\
-  $(mfcalc_sources)
+check_PROGRAMS += %D%/mfcalc
+%C%_mfcalc_LDADD = -lm
+nodist_%C%_mfcalc_SOURCES = $(mfcalc_sources)
 
-examples_mfcalc_mfcalc_CPPFLAGS = -I$(top_builddir)/examples/mfcalc
-dist_TESTS += examples/mfcalc/mfcalc.test
+%C%_mfcalc_CPPFLAGS = -I$(top_builddir)/%D%
+dist_TESTS += %D%/mfcalc.test

examples/rpcalc/.gitignore

@@ -1,4 +1,5 @@
 /calc.h
+/rpcalc
 /rpcalc.c
 /rpcalc.h
 /rpcalc.output

examples/rpcalc/local.mk

@@ -18,18 +18,15 @@
 ## -------------------- ##
 
 BUILT_SOURCES += $(rpcalc_sources)
-CLEANFILES +=  examples/rpcalc/rpcalc.[ch] examples/rpcalc/rpcalc.output
+CLEANFILES +=  %D%/rpcalc.[ch] %D%/rpcalc.output
 
-rpcalc_extracted =				\
-  examples/rpcalc/rpcalc.y
-rpcalc_sources =				\
-  $(rpcalc_extracted)
+rpcalc_extracted = %D%/rpcalc.y
+rpcalc_sources = $(rpcalc_extracted)
 extracted += $(rpcalc_extracted)
 
-check_PROGRAMS += examples/rpcalc/rpcalc
-examples_rpcalc_rpcalc_LDADD = -lm
-nodist_examples_rpcalc_rpcalc_SOURCES =		\
-  $(rpcalc_sources)
+check_PROGRAMS += %D%/rpcalc
+%C%_rpcalc_LDADD = -lm
+nodist_%C%_rpcalc_SOURCES = $(rpcalc_sources)
 
-examples_rpcalc_rpcalc_CPPFLAGS = -I$(top_builddir)/examples/rpcalc
-dist_TESTS += examples/rpcalc/rpcalc.test
+%C%_rpcalc_CPPFLAGS = -I$(top_builddir)/%D%
+dist_TESTS += %D%/rpcalc.test

examples/variant.yy

@@ -16,7 +16,7 @@
 */
 
 %debug
-%skeleton "lalr1.cc"
+%language "c++"
 %defines
 %define api.token.constructor
 %define api.value.type variant
@@ -48,11 +48,17 @@ typedef std::list<std::string> strings_type;
   namespace std
   {
     std::ostream&
-    operator<< (std::ostream& o, const strings_type& s)
+    operator<< (std::ostream& o, const strings_type& ss)
     {
-      std::copy (s.begin (), s.end (),
-                 std::ostream_iterator<strings_type::value_type> (o, "\n"));
-      return o;
+      o << "(" << &ss << ") {";
+      const char *sep = "";
+      for (strings_type::const_iterator i = ss.begin(), end = ss.end();
+           i != end; ++i)
+        {
+          o << sep << *i;
+          sep = ", ";
+        }
+      return o << "}";
     }
   }
 

lib/.gitignore

@@ -272,3 +272,5 @@
 /sig-handler.c
 /unistd.c
 /wctype-h.c
+/lstat.c
+/unlink.c

lib/libiberty.h

@@ -17,7 +17,7 @@
 
 
 /* Bison depends on libiberty's implementation of bitsets, which
-   requires a `libiberty.h' file.  This file provides the minimum
+   requires a 'libiberty.h' file.  This file provides the minimum
    services.  */
 
 #ifndef BISON_LIBIBERTY_H_

lib/local.mk

@@ -51,6 +51,8 @@ lib_libbison_a_SOURCES +=                       \
   lib/get-errno.c
 
 # The Yacc compatibility library.
-lib_LIBRARIES = $(YACC_LIBRARY)
+if ENABLE_YACC
+lib_LIBRARIES = lib/liby.a
 EXTRA_LIBRARIES = lib/liby.a
 lib_liby_a_SOURCES = lib/main.c lib/yyerror.c
+endif

lib/timevar.h

@@ -36,7 +36,7 @@
        Timing variables may be pushed onto the stack; elapsed time is
        attributed to the topmost timing variable on the stack.  When
        another variable is pushed on, the previous topmost variable is
-       `paused' until the pushed variable is popped back off.
+       'paused' until the pushed variable is popped back off.
 
      - As a standalone timer, using timevar_start and timevar_stop.
        All time elapsed between the two calls is attributed to the

m4/.gitignore

@@ -180,3 +180,6 @@
 /obstack-printf.m4
 /extern-inline.m4
 /non-recursive-gnulib-prefix-hack.m4
+/absolute-header.m4
+/lstat.m4
+/unlink.m4

src/AnnotationList.c

@@ -541,9 +541,13 @@ AnnotationList__compute_from_inadequacies (
               {
                 InadequacyList__prependTo (conflict_node,
                                            &inadequacy_lists[s->number]);
-                aver (AnnotationList__insertInto (
-                        annotation_node, &annotation_lists[s->number],
-                        s->nitems));
+                {
+                  bool b =
+                    AnnotationList__insertInto (annotation_node,
+                                                &annotation_lists[s->number],
+                                                s->nitems);
+                  aver (b);
+                }
                 /* This aver makes sure the
                    AnnotationList__computeDominantContribution check above
                    does discard annotations in the simplest case of a S/R

src/Sbitset.c

@@ -60,7 +60,7 @@ Sbitset__isEmpty (Sbitset self, Sbitset__Index nbits)
 }
 
 void
-Sbitset__fprint(Sbitset self, Sbitset__Index nbits, FILE *file)
+Sbitset__fprint (Sbitset self, Sbitset__Index nbits, FILE *file)
 {
   Sbitset__Index i;
   Sbitset itr;

src/Sbitset.h

@@ -44,31 +44,31 @@ void Sbitset__delete (Sbitset self);
 
 bool Sbitset__isEmpty (Sbitset self, Sbitset__Index nbits);
 
-void Sbitset__fprint(Sbitset self, Sbitset__Index nbits, FILE *file);
+void Sbitset__fprint (Sbitset self, Sbitset__Index nbits, FILE *file);
 
 # define Sbitset__set(SELF, INDEX)                                      \
   do {                                                                  \
     *Sbitset__byteAddress ((SELF), (INDEX)) =                           \
       *Sbitset__byteAddress ((SELF), (INDEX)) | Sbitset__bit_mask (INDEX); \
-  } while(0)
+  } while (0)
 
 # define Sbitset__reset(SELF, INDEX)                                    \
   do {                                                                  \
     *Sbitset__byteAddress ((SELF), (INDEX)) =                           \
       *Sbitset__byteAddress ((SELF), (INDEX)) & ~Sbitset__bit_mask (INDEX); \
-  } while(0)
+  } while (0)
 
 /* NBITS is the size of the bitset.  More than NBITS bits might be reset.  */
 # define Sbitset__zero(SELF, NBITS)             \
   do {                                          \
     memset (SELF, 0, Sbitset__nbytes (NBITS));  \
-  } while(0)
+  } while (0)
 
 /* NBITS is the size of the bitset.  More than NBITS bits might be set.  */
 # define Sbitset__ones(SELF, NBITS)                     \
   do {                                                  \
     memset (SELF, UCHAR_MAX, Sbitset__nbytes (NBITS));  \
-  } while(0)
+  } while (0)
 
 /* NBITS is the size of every bitset.  More than NBITS bits might be set.  */
 # define Sbitset__or(SELF, OTHER1, OTHER2, NBITS)                       \
@@ -79,7 +79,7 @@ void Sbitset__fprint(Sbitset self, Sbitset__Index nbits, FILE *file);
     Sbitset end_self = ptr_self + Sbitset__nbytes (NBITS);              \
     for (; ptr_self < end_self; ++ptr_self, ++ptr_other1, ++ptr_other2) \
       *ptr_self = *ptr_other1 | *ptr_other2;                            \
-  } while(0)
+  } while (0)
 
 # define SBITSET__FOR_EACH(SELF, NBITS, ITER, INDEX)                    \
   for ((ITER) = (SELF); (ITER) < (SELF) + Sbitset__nbytes (NBITS); ++(ITER)) \

src/complain.c

@@ -22,6 +22,7 @@
 #include <config.h>
 #include "system.h"
 
+#include <argmatch.h>
 #include <stdarg.h>
 #include <progname.h>
 
@@ -30,42 +31,223 @@
 #include "getargs.h"
 #include "quote.h"
 
-warnings warnings_flag =
-  Wconflicts_sr | Wconflicts_rr | Wdeprecated  | Wother;
-
-warnings errors_flag;
-
 err_status complaint_status = status_none;
+
+bool warnings_are_errors = false;
+
+/** Whether -Werror/-Wno-error was applied to a warning.  */
+typedef enum
+  {
+    errority_unset = 0,     /** No explict status.  */
+    errority_disabled = 1,  /** Explictly disabled with -Wno-error=foo.  */
+    errority_enabled = 2    /** Explictly enabled with -Werror=foo. */
+  } errority;
+
+/** For each warning type, its errority.  */
+static errority errority_flag[warnings_size];
+
+/** Diagnostics severity.  */
+typedef enum
+  {
+    severity_disabled = 0, /**< Explicitly disabled via -Wno-foo.  */
+    severity_unset = 1,    /**< Unspecified status.  */
+    severity_warning = 2,  /**< A warning.  */
+    severity_error = 3,    /**< An error (continue, but die soon).  */
+    severity_fatal = 4     /**< Fatal error (die now).  */
+  } severity;
+
+
+/** For each warning type, its severity.  */
+static severity warnings_flag[warnings_size];
+
 static unsigned *indent_ptr = 0;
 
-void
-warnings_print_categories (warnings warn_flags)
-{
-  if (! (warn_flags & silent))
-    {
-      char const *warn_names[] =
-        {
-          "midrule-values",
-          "yacc",
-          "conflicts-sr",
-          "conflicts-rr",
-          "deprecated",
-          "other"
-        };
+/*------------------------.
+| --warnings's handling.  |
+`------------------------*/
 
-      bool any = false;
-      int i;
-      for (i = 0; i < ARRAY_CARDINALITY (warn_names); ++i)
-        if (warn_flags & 1 << i)
-          {
-            bool err = warn_flags & errors_flag;
-            fprintf (stderr, "%s-W", any ? ", " : " [");
-            fprintf (stderr, "%s%s", err ? "error=" : "" , warn_names[i]);
-            any = true;
-          }
-      if (any)
-        fprintf (stderr, "]");
+static const char * const warnings_args[] =
+{
+  "none",
+  "midrule-values",
+  "yacc",
+  "conflicts-sr",
+  "conflicts-rr",
+  "deprecated",
+  "empty-rule",
+  "precedence",
+  "other",
+  "all",
+  "error",
+  "everything",
+  0
+};
+
+static const int warnings_types[] =
+{
+  Wnone,
+  Wmidrule_values,
+  Wyacc,
+  Wconflicts_sr,
+  Wconflicts_rr,
+  Wdeprecated,
+  Wempty_rule,
+  Wprecedence,
+  Wother,
+  Wall,
+  Werror,
+  Weverything
+};
+
+ARGMATCH_VERIFY (warnings_args, warnings_types);
+
+void
+warning_argmatch (char const *arg, size_t no, size_t err)
+{
+  int value = XARGMATCH ("--warning", arg + no + err,
+                         warnings_args, warnings_types);
+
+  /* -Wnone == -Wno-everything, and -Wno-none == -Weverything.  */
+  if (!value)
+    {
+      value = Weverything;
+      no = !no;
     }
+
+  size_t b;
+  for (b = 0; b < warnings_size; ++b)
+    if (value & 1 << b)
+      {
+        if (err && no)
+          /* -Wno-error=foo.  */
+          errority_flag[b] = errority_disabled;
+        else if (err && !no)
+          {
+            /* -Werror=foo: enables -Wfoo. */
+            errority_flag[b] = errority_enabled;
+            warnings_flag[b] = severity_warning;
+          }
+        else if (no)
+          /* -Wno-foo.  */
+          warnings_flag[b] = severity_disabled;
+        else
+          /* -Wfoo. */
+          warnings_flag[b] = severity_warning;
+      }
+}
+
+/** Decode a comma-separated list of arguments from -W.
+ *
+ *  \param args     comma separated list of effective subarguments to decode.
+ *                  If 0, then activate all the flags.
+ */
+
+void
+warnings_argmatch (char *args)
+{
+  if (args)
+    for (args = strtok (args, ","); args; args = strtok (NULL, ","))
+      if (STREQ (args, "error"))
+        warnings_are_errors = true;
+      else if (STREQ (args, "no-error"))
+        warnings_are_errors = false;
+      else
+        {
+          /* The length of the possible 'no-' prefix: 3, or 0.  */
+          size_t no = STRPREFIX_LIT ("no-", args) ? 3 : 0;
+          /* The length of the possible 'error=' (possibly after
+             'no-') prefix: 6, or 0. */
+          size_t err = STRPREFIX_LIT ("error=", args + no) ? 6 : 0;
+
+          warning_argmatch (args, no, err);
+        }
+  else
+    warning_argmatch ("all", 0, 0);
+}
+
+
+/*-----------.
+| complain.  |
+`-----------*/
+
+void
+complain_init (void)
+{
+  warnings warnings_default =
+    Wconflicts_sr | Wconflicts_rr | Wdeprecated | Wother;
+
+  size_t b;
+  for (b = 0; b < warnings_size; ++b)
+    {
+      warnings_flag[b] = (1 << b & warnings_default
+                          ? severity_warning
+                          : severity_unset);
+      errority_flag[b] = errority_unset;
+    }
+}
+
+
+/* A diagnostic with FLAGS is about to be issued.  With what severity?
+   (severity_fatal, severity_error, severity_disabled, or
+   severity_warning.) */
+
+static severity
+warning_severity (warnings flags)
+{
+  if (flags & fatal)
+    /* Diagnostics about fatal errors.  */
+    return severity_fatal;
+  else if (flags & complaint)
+    /* Diagnostics about errors.  */
+    return severity_error;
+  else
+    {
+      /* Diagnostics about warnings.  */
+      severity res = severity_disabled;
+      size_t b;
+      for (b = 0; b < warnings_size; ++b)
+        if (flags & 1 << b)
+          {
+            res = res < warnings_flag[b] ? warnings_flag[b] : res;
+            /* If the diagnostic is enabled, and -Werror is enabled,
+               and -Wno-error=foo was not explicitly requested, this
+               is an error. */
+            if (res == severity_warning
+                && (errority_flag[b] == errority_enabled
+                    || (warnings_are_errors
+                        && errority_flag[b] != errority_disabled)))
+              res = severity_error;
+          }
+      return res;
+    }
+}
+
+bool
+warning_is_unset (warnings flags)
+{
+  size_t b;
+  for (b = 0; b < warnings_size; ++b)
+    if (flags & 1 << b && warnings_flag[b] != severity_unset)
+      return false;
+  return true;
+}
+
+/** Display a "[-Wyacc]" like message on \a f.  */
+
+static void
+warnings_print_categories (warnings warn_flags, FILE *f)
+{
+  /* Display only the first match, the second is "-Wall".  */
+  size_t i;
+  for (i = 0; warnings_args[i]; ++i)
+    if (warn_flags & warnings_types[i])
+      {
+        severity s = warning_severity (warnings_types[i]);
+        fprintf (f, " [-W%s%s]",
+                 s == severity_error ? "error=" : "",
+                 warnings_args[i]);
+        return;
+      }
 }
 
 /** Report an error message.
@@ -88,7 +270,7 @@ error_message (const location *loc, warnings flags, const char *prefix,
   unsigned pos = 0;
 
   if (loc)
-    pos += location_print (stderr, *loc);
+    pos += location_print (*loc, stderr);
   else
     pos += fprintf (stderr, "%s", current_file ? current_file : program_name);
   pos += fprintf (stderr, ": ");
@@ -108,7 +290,8 @@ error_message (const location *loc, warnings flags, const char *prefix,
     fprintf (stderr, "%s: ", prefix);
 
   vfprintf (stderr, message, args);
-  warnings_print_categories (flags);
+  if (! (flags & silent))
+    warnings_print_categories (flags, stderr);
   {
     size_t l = strlen (message);
     if (l < 2 || message[l - 2] != ':' || message[l - 1] != ' ')
@@ -116,29 +299,34 @@ error_message (const location *loc, warnings flags, const char *prefix,
         putc ('\n', stderr);
         fflush (stderr);
         if (loc && feature_flag & feature_caret && !(flags & no_caret))
-          location_caret (stderr, *loc);
+          location_caret (*loc, stderr);
       }
   }
   fflush (stderr);
 }
 
-/** Raise a complaint. That can be a fatal error, a complaint or just a
+/** Raise a complaint. That can be a fatal error, an error or just a
     warning.  */
-static inline void
+
+static void
 complains (const location *loc, warnings flags, const char *message,
            va_list args)
 {
-  const char* prefix =
-    flags & fatal ? _("fatal error")
-    : flags & (errors_flag | complaint) ? _("error")
-    : _("warning");
-
+  severity s = warning_severity (flags);
   if ((flags & complaint) && complaint_status < status_complaint)
     complaint_status = status_complaint;
-  else if ((flags & (warnings_flag & errors_flag)) && ! complaint_status)
-    complaint_status = status_warning_as_error;
-  if (flags & (warnings_flag | fatal | complaint))
-    error_message (loc, flags, prefix, message, args);
+
+  if (severity_warning <= s)
+    {
+      const char* prefix =
+        s == severity_fatal ? _("fatal error")
+        : s == severity_error ? _("error")
+        : _("warning");
+      if (severity_error <= s && ! complaint_status)
+        complaint_status = status_warning_as_error;
+      error_message (loc, flags, prefix, message, args);
+    }
+
   if (flags & fatal)
     exit (EXIT_FAILURE);
 }
@@ -189,7 +377,6 @@ complain_args (location const *loc, warnings w, unsigned *indent,
     complain (loc, fatal, "too many arguments for complains");
     break;
   }
-
 }
 
 void
@@ -204,3 +391,13 @@ deprecated_directive (location const *loc, char const *old, char const *upd)
               _("deprecated directive: %s, use %s"),
               quote (old), quote_n (1, upd));
 }
+
+void
+duplicate_directive (char const *directive,
+                     location first, location second)
+{
+  unsigned i = 0;
+  complain (&second, complaint, _("only one %s allowed per rule"), directive);
+  i += SUB_INDENT;
+  complain_indent (&first, complaint, &i, _("previous declaration"));
+}

src/complain.h

@@ -28,15 +28,67 @@
 | --warnings.  |
 `-------------*/
 
+/** The bits assigned to each warning type.  */
 typedef enum
   {
-    Wnone             = 0,       /**< Issue no warnings.  */
-    Wmidrule_values   = 1 << 0,  /**< Unset or unused midrule values.  */
-    Wyacc             = 1 << 1,  /**< POSIXME.  */
-    Wconflicts_sr     = 1 << 2,  /**< S/R conflicts.  */
-    Wconflicts_rr     = 1 << 3,  /**< R/R conflicts.  */
-    Wdeprecated       = 1 << 4,  /**< Obsolete constructs.  */
-    Wother            = 1 << 5,  /**< All other warnings.  */
+    warning_midrule_values, /**< Unset or unused midrule values.  */
+    warning_yacc,           /**< POSIXME.  */
+    warning_conflicts_sr,   /**< S/R conflicts.  */
+    warning_conflicts_rr,   /**< R/R conflicts.  */
+    warning_empty_rule,     /**< Implicitly empty rules.  */
+    warning_deprecated,     /**< Obsolete constructs.  */
+    warning_precedence,     /**< Useless precedence and associativity.  */
+    warning_other,          /**< All other warnings.  */
+
+    warnings_size           /**< The number of warnings.  Must be last.  */
+  } warning_bit;
+
+/** Whether -Werror was set. */
+extern bool warnings_are_errors;
+
+/** Decode a single argument from -W.
+ *
+ *  \param arg      the subarguments to decode.
+ *                  If null, then activate all the flags.
+ *  \param no       length of the potential "no-" prefix.
+ *                  Can be 0 or 3. If 3, negate the action of the subargument.
+ *  \param err      length of a potential "error=".
+ *                  Can be 0 or 6. If 6, treat the subargument as a CATEGORY.
+ *
+ *  If VALUE != 0 then KEY sets flags and no-KEY clears them.
+ *  If VALUE == 0 then KEY clears all flags from \c all and no-KEY sets all
+ *  flags from \c all.  Thus no-none = all and no-all = none.
+ */
+void warning_argmatch (char const *arg, size_t no, size_t err);
+
+/** Decode a comma-separated list of arguments from -W.
+ *
+ *  \param args     comma separated list of effective subarguments to decode.
+ *                  If 0, then activate all the flags.
+ */
+void warnings_argmatch (char *args);
+
+
+/*-----------.
+| complain.  |
+`-----------*/
+
+/** Initialize this module.  */
+void complain_init (void);
+
+typedef enum
+  {
+    /**< Issue no warnings.  */
+    Wnone             = 0,
+
+    Wmidrule_values   = 1 << warning_midrule_values,
+    Wyacc             = 1 << warning_yacc,
+    Wconflicts_sr     = 1 << warning_conflicts_sr,
+    Wconflicts_rr     = 1 << warning_conflicts_rr,
+    Wdeprecated       = 1 << warning_deprecated,
+    Wempty_rule       = 1 << warning_empty_rule,
+    Wprecedence       = 1 << warning_precedence,
+    Wother            = 1 << warning_other,
 
     Werror            = 1 << 10, /** This bit is no longer used. */
 
@@ -46,17 +98,13 @@ typedef enum
     no_caret          = 1 << 14, /**< Do not display caret location.  */
 
     /**< All above warnings.  */
-    Wall              = ~complaint & ~fatal & ~silent
+    Weverything       = ~complaint & ~fatal & ~silent,
+    Wall              = Weverything & ~Wyacc
   } warnings;
 
-/** What warnings are issued.  */
-extern warnings warnings_flag;
-
-/** What warnings are made errors.  */
-extern warnings errors_flag;
-
-/** Display a "[-Wyacc]" like message on stderr.  */
-void warnings_print_categories (warnings warn_flags);
+/** Whether the warnings of \a flags are all unset.
+    (Never enabled, never disabled). */
+bool warning_is_unset (warnings flags);
 
 /** Make a complaint, with maybe a location.  */
 void complain (location const *loc, warnings flags, char const *message, ...)
@@ -76,14 +124,18 @@ void complain_indent (location const *loc, warnings flags, unsigned *indent,
 void deprecated_directive (location const *loc,
                            char const *obsolete, char const *updated);
 
-/** Warnings treated as errors shouldn't stop the execution as regular errors
-    should (because due to their nature, it is safe to go on). Thus, there are
-    three possible execution statuses.  */
+/** Report a repeated directive for a rule.  */
+void duplicate_directive (char const *directive,
+                          location first, location second);
+
+/** Warnings treated as errors shouldn't stop the execution as regular
+    errors should (because due to their nature, it is safe to go
+    on). Thus, there are three possible execution statuses.  */
 typedef enum
   {
-    status_none,
-    status_warning_as_error,
-    status_complaint
+    status_none,             /**< No diagnostic issued so far.  */
+    status_warning_as_error, /**< A warning was issued (but no error).  */
+    status_complaint         /**< An error was issued.  */
   } err_status;
 
 /** Whether an error was reported.  */

src/conflicts.c

@@ -403,7 +403,7 @@ conflicts_solve (void)
       set_conflicts (states[i], errors);
 
       /* For uniformity of the code, make sure all the states have a valid
-         `errs' member.  */
+         'errs' member.  */
       if (!states[i]->errs)
         states[i]->errs = errs_new (0, 0);
     }

src/files.c

@@ -34,7 +34,7 @@
 #include "getargs.h"
 #include "gram.h"
 
-/* Initializing some values below (such SPEC_NAME_PREFIX to `yy') is
+/* Initializing some values below (such SPEC_NAME_PREFIX to 'yy') is
    tempting, but don't do that: for the time being our handling of the
    %directive vs --option leaves precedence to the options by deciding
    that if a %directive sets a variable which is really set (i.e., not
@@ -51,27 +51,36 @@ char *spec_defines_file = NULL;  /* for --defines. */
 char *parser_file_name;
 
 /* All computed output file names.  */
-static char **file_names = NULL;
-static int file_names_count = 0;
+typedef struct generated_file
+{
+  /** File name.  */
+  char *name;
+  /** Whether is a generated source file (e.g., *.c, *.java...), as
+      opposed to the report file (e.g., *.output).  When late errors
+      are detected, generated source files are removed.  */
+  bool is_source;
+} generated_file;
+static generated_file *generated_files = NULL;
+static int generated_files_size = 0;
 
 uniqstr grammar_file = NULL;
 uniqstr current_file = NULL;
 
 /* If --output=dir/foo.c was specified,
-   DIR_PREFIX is `dir/' and ALL_BUT_EXT and ALL_BUT_TAB_EXT are `dir/foo'.
+   DIR_PREFIX is 'dir/' and ALL_BUT_EXT and ALL_BUT_TAB_EXT are 'dir/foo'.
 
-   If --output=dir/foo.tab.c was specified, DIR_PREFIX is `dir/',
-   ALL_BUT_EXT is `dir/foo.tab', and ALL_BUT_TAB_EXT is `dir/foo'.
+   If --output=dir/foo.tab.c was specified, DIR_PREFIX is 'dir/',
+   ALL_BUT_EXT is 'dir/foo.tab', and ALL_BUT_TAB_EXT is 'dir/foo'.
 
    If --output was not specified but --file-prefix=dir/foo was specified,
-   ALL_BUT_EXT = `foo.tab' and ALL_BUT_TAB_EXT = `foo'.
+   ALL_BUT_EXT = 'foo.tab' and ALL_BUT_TAB_EXT = 'foo'.
 
    If neither --output nor --file was specified but the input grammar
-   is name dir/foo.y, ALL_BUT_EXT and ALL_BUT_TAB_EXT are `foo'.
+   is name dir/foo.y, ALL_BUT_EXT and ALL_BUT_TAB_EXT are 'foo'.
 
    If neither --output nor --file was specified, DIR_PREFIX is the
    empty string (meaning the current directory); otherwise it is
-   `dir/'.  */
+   'dir/'.  */
 
 char *all_but_ext;
 static char *all_but_tab_ext;
@@ -79,7 +88,7 @@ char *dir_prefix;
 
 /* C source file extension (the parser source).  */
 static char *src_extension = NULL;
-/* Header file extension (if option ``-d'' is specified).  */
+/* Header file extension (if option '`-d'' is specified).  */
 static char *header_extension = NULL;
 
 /*-----------------------------------------------------------------.
@@ -191,7 +200,7 @@ compute_exts_from_src (const char *ext)
    *EXT points to the last period in the basename, or NULL if none.
 
    If there is no *EXT, *TAB is NULL.  Otherwise, *TAB points to
-   `.tab' or `_tab' if present right before *EXT, or is NULL. *TAB
+   '.tab' or '_tab' if present right before *EXT, or is NULL. *TAB
    cannot be equal to *BASE.
 
    None are allocated, they are simply pointers to parts of FILE_NAME.
@@ -222,7 +231,7 @@ file_name_split (const char *file_name,
   *ext = strrchr (*base, '.');
   *tab = NULL;
 
-  /* If there is an extension, check if there is a `.tab' part right
+  /* If there is an extension, check if there is a '.tab' part right
      before.  */
   if (*ext)
     {
@@ -270,7 +279,7 @@ compute_file_name_parts (void)
 
       if (spec_file_prefix)
         {
-          /* If --file-prefix=foo was specified, ALL_BUT_TAB_EXT = `foo'.  */
+          /* If --file-prefix=foo was specified, ALL_BUT_TAB_EXT = 'foo'.  */
           dir_prefix =
             xstrndup (spec_file_prefix,
                       last_component (spec_file_prefix) - spec_file_prefix);
@@ -278,14 +287,14 @@ compute_file_name_parts (void)
         }
       else if (yacc_flag)
         {
-          /* If --yacc, then the output is `y.tab.c'.  */
+          /* If --yacc, then the output is 'y.tab.c'.  */
           dir_prefix = xstrdup ("");
           all_but_tab_ext = xstrdup ("y");
         }
       else
         {
           /* Otherwise, ALL_BUT_TAB_EXT is computed from the input
-             grammar: `foo/bar.yy' => `bar'.  */
+             grammar: 'foo/bar.yy' => 'bar'.  */
           dir_prefix = xstrdup ("");
           all_but_tab_ext =
             xstrndup (base, (strlen (base) - (ext ? strlen (ext) : 0)));
@@ -332,21 +341,21 @@ compute_output_file_names (void)
     {
       if (! spec_graph_file)
         spec_graph_file = concat2 (all_but_tab_ext, ".dot");
-      output_file_name_check (&spec_graph_file);
+      output_file_name_check (&spec_graph_file, false);
     }
 
   if (xml_flag)
     {
       if (! spec_xml_file)
         spec_xml_file = concat2 (all_but_tab_ext, ".xml");
-      output_file_name_check (&spec_xml_file);
+      output_file_name_check (&spec_xml_file, false);
     }
 
   if (report_flag)
     {
       if (!spec_verbose_file)
         spec_verbose_file = concat2 (all_but_tab_ext, OUTPUT_EXT);
-      output_file_name_check (&spec_verbose_file);
+      output_file_name_check (&spec_verbose_file, false);
     }
 
   free (all_but_tab_ext);
@@ -355,7 +364,7 @@ compute_output_file_names (void)
 }
 
 void
-output_file_name_check (char **file_name)
+output_file_name_check (char **file_name, bool source)
 {
   bool conflict = false;
   if (STREQ (*file_name, grammar_file))
@@ -367,11 +376,11 @@ output_file_name_check (char **file_name)
   else
     {
       int i;
-      for (i = 0; i < file_names_count; i++)
-        if (STREQ (file_names[i], *file_name))
+      for (i = 0; i < generated_files_size; i++)
+        if (STREQ (generated_files[i].name, *file_name))
           {
             complain (NULL, Wother, _("conflicting outputs to file %s"),
-                      quote (*file_name));
+                      quote (generated_files[i].name));
             conflict = true;
           }
     }
@@ -382,12 +391,23 @@ output_file_name_check (char **file_name)
     }
   else
     {
-      file_names = xnrealloc (file_names, ++file_names_count,
-                              sizeof *file_names);
-      file_names[file_names_count-1] = xstrdup (*file_name);
+      generated_files = xnrealloc (generated_files, ++generated_files_size,
+                                   sizeof *generated_files);
+      generated_files[generated_files_size-1].name = xstrdup (*file_name);
+      generated_files[generated_files_size-1].is_source = source;
     }
 }
 
+void
+unlink_generated_sources (void)
+{
+  int i;
+  for (i = 0; i < generated_files_size; i++)
+    if (generated_files[i].is_source)
+      /* Ignore errors.  The file might not even exist.  */
+      unlink (generated_files[i].name);
+}
+
 void
 output_file_names_free (void)
 {
@@ -400,8 +420,8 @@ output_file_names_free (void)
   free (dir_prefix);
   {
     int i;
-    for (i = 0; i < file_names_count; i++)
-      free (file_names[i]);
+    for (i = 0; i < generated_files_size; i++)
+      free (generated_files[i].name);
   }
-  free (file_names);
+  free (generated_files);
 }

src/files.h

@@ -63,7 +63,15 @@ extern char *all_but_ext;
 
 void compute_output_file_names (void);
 void output_file_names_free (void);
-void output_file_name_check (char **file_name);
+
+/** Record that we generate file \a file_name.
+ *  \param source whether this is a source file (*c, *.java...)
+ *                as opposed to a report (*.output, *.dot...).
+ */
+void output_file_name_check (char **file_name, bool source);
+
+/** Remove all the generated source files. */
+void unlink_generated_sources (void);
 
 FILE *xfopen (const char *name, char const *mode);
 void xfclose (FILE *ptr);

src/getargs.c

@@ -61,7 +61,6 @@ int skeleton_prio = default_prio;
 const char *skeleton = NULL;
 int language_prio = default_prio;
 struct bison_language const *language = &valid_languages[0];
-const char *include = NULL;
 
 /** Decode an option's key.
  *
@@ -74,8 +73,6 @@ const char *include = NULL;
  *                  If null, then activate all the flags.
  *  \param no       length of the potential "no-" prefix.
  *                  Can be 0 or 3. If 3, negate the action of the subargument.
- *  \param err      length of a potential "error=".
- *                  Can be 0 or 6. If 6, treat the subargument as a CATEGORY
  *
  *  If VALUE != 0 then KEY sets flags and no-KEY clears them.
  *  If VALUE == 0 then KEY clears all flags from \c all and no-KEY sets all
@@ -84,36 +81,23 @@ const char *include = NULL;
 static void
 flag_argmatch (const char *option,
                const char * const keys[], const int values[],
-               int all, int *flags, char *arg, size_t no, size_t err)
+               int all, int *flags, char *arg, size_t no)
 {
-  int value = 0;
-  if (!err || arg[no + err++] != '\0')
-    value = XARGMATCH (option, arg + no + err, keys, values);
+  int value = XARGMATCH (option, arg + no, keys, values);
 
-  if (value)
+  /* -rnone == -rno-all, and -rno-none == -rall.  */
+  if (!value)
     {
-      if (no)
-        *flags &= ~value;
-      else
-        {
-          if (err)
-            warnings_flag |= value;
-          *flags |= value;
-        }
+      value = all;
+      no = !no;
     }
+
+  if (no)
+    *flags &= ~value;
   else
-    {
-      /* With a simpler 'if (no)' version, -Werror means -Werror=all
-         (or rather, -Werror=no-none, but that syntax is invalid).
-         The difference is:
-         - Werror activates all errors, but not the warnings
-         - Werror=all activates errors, and all warnings */
-      if (no ? !err : err)
-        *flags |= all;
-      else
-        *flags &= ~all;
-    }
+    *flags |= value;
 }
+
 /** Decode an option's set of keys.
  *
  *  \param option   option being decoded.
@@ -133,16 +117,14 @@ flags_argmatch (const char *option,
     for (args = strtok (args, ","); args; args = strtok (NULL, ","))
       {
         size_t no = STRPREFIX_LIT ("no-", args) ? 3 : 0;
-        size_t err = STRPREFIX_LIT ("error", args + no) ? 5 : 0;
-
         flag_argmatch (option, keys,
-                       values, all, err ? &errors_flag : flags,
-                       args, no, err);
+                       values, all, flags, args, no);
       }
   else
     *flags |= all;
 }
 
+
 /** Decode a set of sub arguments.
  *
  *  \param FlagName  the flag familly to update.
@@ -196,8 +178,6 @@ ARGMATCH_VERIFY (report_args, report_types);
 
 static const char * const trace_args[] =
 {
-  /* In a series of synonyms, present the most meaningful first, so
-     that argmatch_valid be more readable.  */
   "none       - no traces",
   "scan       - grammar scanner traces",
   "parse      - grammar parser traces",
@@ -238,41 +218,6 @@ static const int trace_types[] =
 ARGMATCH_VERIFY (trace_args, trace_types);
 
 
-/*------------------------.
-| --warnings's handling.  |
-`------------------------*/
-
-static const char * const warnings_args[] =
-{
-  /* In a series of synonyms, present the most meaningful first, so
-     that argmatch_valid be more readable.  */
-  "none            - no warnings",
-  "midrule-values  - unset or unused midrule values",
-  "yacc            - incompatibilities with POSIX Yacc",
-  "conflicts-sr    - S/R conflicts",
-  "conflicts-rr    - R/R conflicts",
-  "deprecated      - obsolete constructs",
-  "other           - all other warnings",
-  "all             - all of the above",
-  "error           - warnings are errors",
-  0
-};
-
-static const int warnings_types[] =
-{
-  Wnone,
-  Wmidrule_values,
-  Wyacc,
-  Wconflicts_sr,
-  Wconflicts_rr,
-  Wdeprecated,
-  Wother,
-  Wall,
-  Werror
-};
-
-ARGMATCH_VERIFY (warnings_args, warnings_types);
-
 /*-----------------------.
 | --feature's handling.  |
 `-----------------------*/
@@ -304,7 +249,7 @@ static void
 usage (int status)
 {
   if (status != 0)
-    fprintf (stderr, _("Try `%s --help' for more information.\n"),
+    fprintf (stderr, _("Try '%s --help' for more information.\n"),
              program_name);
   else
     {
@@ -346,7 +291,7 @@ Parser:\n\
   -L, --language=LANGUAGE          specify the output programming language\n\
   -S, --skeleton=FILE              specify the skeleton to use\n\
   -t, --debug                      instrument the parser for tracing\n\
-                                   same as `-Dparse.trace'\n\
+                                   same as '-Dparse.trace'\n\
       --locations                  enable location support\n\
   -D, --define=NAME[=VALUE]        similar to '%define NAME \"VALUE\"'\n\
   -F, --force-define=NAME[=VALUE]  override '%define NAME \"VALUE\"'\n\
@@ -365,7 +310,7 @@ Output:\n\
   -d                         likewise but cannot specify FILE (for POSIX Yacc)\n\
   -r, --report=THINGS        also produce details on the automaton\n\
       --report-file=FILE     write report to FILE\n\
-  -v, --verbose              same as `--report=state'\n\
+  -v, --verbose              same as '--report=state'\n\
   -b, --file-prefix=PREFIX   specify a PREFIX for output files\n\
   -o, --output=FILE          leave output to FILE\n\
   -g, --graph[=FILE]         also output a graph of the automaton\n\
@@ -376,35 +321,37 @@ Output:\n\
 
       fputs (_("\
 Warning categories include:\n\
-  `midrule-values'    unset or unused midrule values\n\
-  `yacc'              incompatibilities with POSIX Yacc\n\
-  `conflicts-sr'      S/R conflicts (enabled by default)\n\
-  `conflicts-rr'      R/R conflicts (enabled by default)\n\
-  `deprecated'        obsolete constructs\n\
-  `other'             all other warnings (enabled by default)\n\
-  `all'               all the warnings\n\
-  `no-CATEGORY'       turn off warnings in CATEGORY\n\
-  `none'              turn off all the warnings\n\
-  `error[=CATEGORY]'  treat warnings as errors\n\
+  'midrule-values'    unset or unused midrule values\n\
+  'yacc'              incompatibilities with POSIX Yacc\n\
+  'conflicts-sr'      S/R conflicts (enabled by default)\n\
+  'conflicts-rr'      R/R conflicts (enabled by default)\n\
+  'deprecated'        obsolete constructs\n\
+  'empty-rule'        empty rules without %empty\n\
+  'precedence'        useless precedence and associativity\n\
+  'other'             all other warnings (enabled by default)\n\
+  'all'               all the warnings except 'yacc'\n\
+  'no-CATEGORY'       turn off warnings in CATEGORY\n\
+  'none'              turn off all the warnings\n\
+  'error[=CATEGORY]'  treat warnings as errors\n\
 "), stdout);
       putc ('\n', stdout);
 
       fputs (_("\
 THINGS is a list of comma separated words that can include:\n\
-  `state'        describe the states\n\
-  `itemset'      complete the core item sets with their closure\n\
-  `lookahead'    explicitly associate lookahead tokens to items\n\
-  `solved'       describe shift/reduce conflicts solving\n\
-  `all'          include all the above information\n\
-  `none'         disable the report\n\
+  'state'        describe the states\n\
+  'itemset'      complete the core item sets with their closure\n\
+  'lookahead'    explicitly associate lookahead tokens to items\n\
+  'solved'       describe shift/reduce conflicts solving\n\
+  'all'          include all the above information\n\
+  'none'         disable the report\n\
 "), stdout);
       putc ('\n', stdout);
 
       fputs (_("\
 FEATURE is a list of comma separated words that can include:\n\
-  `caret'        show errors with carets\n\
-  `all'          all of the above\n\
-  `none'         disable all of the above\n\
+  'caret'        show errors with carets\n\
+  'all'          all of the above\n\
+  'none'         disable all of the above\n\
   "), stdout);
 
       putc ('\n', stdout);
@@ -517,12 +464,10 @@ static char const short_options[] =
   "b:"
   "d"
   "f::"
-  "e"
   "g::"
   "h"
   "k"
   "l"
-  "n"
   "o:"
   "p:"
   "r:"
@@ -552,7 +497,6 @@ static struct option const long_options[] =
 
   /* Parser. */
   { "name-prefix",   required_argument,   0,   'p' },
-  { "include",       required_argument,   0,   'I' },
 
   /* Output. */
   { "file-prefix", required_argument,   0,   'b' },
@@ -581,7 +525,6 @@ static struct option const long_options[] =
   { "force-define",   required_argument,         0,   'F' },
   { "locations",      no_argument,               0, LOCATIONS_OPTION },
   { "no-lines",       no_argument,               0,   'l' },
-  { "raw",            no_argument,               0,     0 },
   { "skeleton",       required_argument,         0,   'S' },
   { "language",       required_argument,         0,   'L' },
   { "token-table",    no_argument,               0,   'k' },
@@ -590,7 +533,7 @@ static struct option const long_options[] =
 };
 
 /* Under DOS, there is no difference on the case.  This can be
-   troublesome when looking for `.tab' etc.  */
+   troublesome when looking for '.tab' etc.  */
 #ifdef MSDOS
 # define AS_FILE_NAME(File) (strlwr (File), (File))
 #else
@@ -626,24 +569,36 @@ getargs (int argc, char *argv[])
         /* Certain long options cause getopt_long to return 0.  */
         break;
 
-      case 'D': /* -DNAME[=VALUE]. */
-      case 'F': /* -FNAME[=VALUE]. */
+      case 'D': /* -DNAME[=(VALUE|"VALUE"|{VALUE})]. */
+      case 'F': /* -FNAME[=(VALUE|"VALUE"|{VALUE})]. */
         {
-          char* name = optarg;
-          char* value = strchr (optarg, '=');
+          char *name = optarg;
+          char *value = strchr (optarg, '=');
+          muscle_kind kind = muscle_keyword;
           if (value)
-            *value++ = 0;
+            {
+              char *end = value + strlen (value) - 1;
+              *value++ = 0;
+              if (*value == '{' && *end == '}')
+                {
+                  kind = muscle_code;
+                  ++value;
+                  *end = 0;
+                }
+              else if (*value == '"' && *end == '"')
+                {
+                  kind = muscle_string;
+                  ++value;
+                  *end = 0;
+                }
+            }
           muscle_percent_define_insert (name, command_line_location (),
-                                        value ? value : "",
+                                        kind, value ? value : "",
                                         c == 'D' ? MUSCLE_PERCENT_DEFINE_D
                                                  : MUSCLE_PERCENT_DEFINE_F);
         }
         break;
 
-      case 'I':
-        include = AS_FILE_NAME (optarg);
-        break;
-
       case 'L':
         language_argmatch (optarg, command_line_prio,
                            command_line_location ());
@@ -667,7 +622,7 @@ getargs (int argc, char *argv[])
         break;
 
       case 'W':
-        FLAGS_ARGMATCH (warnings, optarg, Wall);
+        warnings_argmatch (optarg);
         break;
 
       case 'b':
@@ -718,7 +673,8 @@ getargs (int argc, char *argv[])
 
       case 't':
         muscle_percent_define_insert ("parse.trace",
-                                      command_line_location (), "",
+                                      command_line_location (),
+                                      muscle_keyword, "",
                                       MUSCLE_PERCENT_DEFINE_D);
         break;
 
@@ -736,8 +692,7 @@ getargs (int argc, char *argv[])
         break;
 
       case 'y':
-        warnings_flag |= Wyacc;
-        errors_flag |= Wyacc;
+        warning_argmatch ("error=yacc", 0, 6);
         yacc_flag = true;
         break;
 

src/getargs.h

@@ -121,6 +121,7 @@ enum feature
 /** What additional features to use.  */
 extern int feature_flag;
 
+
 /** Process the command line arguments.
  *
  *  \param argc   size of \a argv

src/gram.c

@@ -93,16 +93,14 @@ rule_rhs_length (rule const *r)
 void
 rule_rhs_print (rule const *r, FILE *out)
 {
-  if (*r->rhs >= 0)
+  if (0 <= *r->rhs)
     {
       item_number *rp;
       for (rp = r->rhs; *rp >= 0; rp++)
         fprintf (out, " %s", symbols[*rp]->tag);
     }
   else
-    {
-      fprintf (out, " /* %s */", _("empty"));
-    }
+    fputs (" %empty", out);
 }
 
 static void
@@ -125,13 +123,6 @@ rule_rhs_print_xml (rule const *r, FILE *out, int level)
     }
 }
 
-static void
-rule_print (rule const *r, FILE *out)
-{
-  fprintf (out, "%s:", r->lhs->tag);
-  rule_rhs_print (r, out);
-}
-
 void
 ritem_print (FILE *out)
 {
@@ -289,8 +280,8 @@ grammar_dump (FILE *out, const char *title)
     rule_number r;
     for (r = 0; r < nrules + nuseless_productions; r++)
       {
-        fprintf (out, "%-5d  ", r);
-        rule_print (&rules[r], out);
+        fprintf (out, "%-5d  %s:", r, rules[r].lhs->tag);
+        rule_rhs_print (&rules[r], out);
         fprintf (out, "\n");
       }
   }
@@ -300,24 +291,10 @@ grammar_dump (FILE *out, const char *title)
 void
 grammar_rules_useless_report (const char *message)
 {
-  warnings w = Wother;
-  if (warnings_flag & w)
-    {
-      rule_number r;
-      for (r = 0; r < nrules ; ++r)
-        if (!rules[r].useful)
-          {
-            if (feature_flag & feature_caret)
-              complain (&rules[r].location, w, "%s", message);
-            else
-              {
-                complain (&rules[r].location, w | silent, "%s: ", message);
-                rule_print (&rules[r], stderr);
-                warnings_print_categories (w);
-                fprintf (stderr, "\n");
-              }
-          }
-    }
+  rule_number r;
+  for (r = 0; r < nrules ; ++r)
+    if (!rules[r].useful)
+      complain (&rules[r].location, Wother, "%s", message);
 }
 
 void

src/gram.h

@@ -35,7 +35,7 @@
 
    The rules receive rule numbers 1 to NRULES in the order they are
    written.  More precisely Bison augments the grammar with the
-   initial rule, `$accept: START-SYMBOL $end', which is numbered 1,
+   initial rule, '$accept: START-SYMBOL $end', which is numbered 1,
    all the user rules are 2, 3 etc.  Each time a rule number is
    presented to the user, we subtract 1, so *displayed* rule numbers
    are 0, 1, 2...
@@ -61,7 +61,7 @@
    RULES[R].prec -- the symbol providing the precedence level of R.
 
    RULES[R].precsym -- the symbol attached (via %prec) to give its
-   precedence to R.  Of course, if set, it is equal to `prec', but we
+   precedence to R.  Of course, if set, it is equal to 'prec', but we
    need to distinguish one from the other when reducing: a symbol used
    in a %prec is not useless.
 
@@ -205,11 +205,11 @@ extern rule *rules;
 /* A function that selects a rule.  */
 typedef bool (*rule_filter) (rule const *);
 
-/* Return true IFF the rule has a `number' smaller than NRULES.  That is, it is
+/* Return true IFF the rule has a 'number' smaller than NRULES.  That is, it is
    useful in the grammar.  */
 bool rule_useful_in_grammar_p (rule const *r);
 
-/* Return true IFF the rule has a `number' higher than NRULES.  That is, it is
+/* Return true IFF the rule has a 'number' higher than NRULES.  That is, it is
    useless in the grammar.  */
 bool rule_useless_in_grammar_p (rule const *r);
 
@@ -262,8 +262,8 @@ void grammar_rules_print_xml (FILE *out, int level);
 void grammar_dump (FILE *out, const char *title);
 
 /* Report on STDERR the rules that are not flagged USEFUL, using the
-   MESSAGE (which can be `rule useless in grammar' when invoked after grammar
-   reduction, or `rule useless in parser due to conflicts' after conflicts
+   MESSAGE (which can be 'rule useless in grammar' when invoked after grammar
+   reduction, or 'rule useless in parser due to conflicts' after conflicts
    were taken into account).  */
 void grammar_rules_useless_report (const char *message);
 

src/lalr.c

@@ -67,17 +67,13 @@ static goto_number **includes;
 static goto_list **lookback;
 
 
-
-
 void
 set_goto_map (void)
 {
   state_number s;
-  goto_number *temp_map;
+  goto_number *temp_map = xnmalloc (nvars + 1, sizeof *temp_map);
 
   goto_map = xcalloc (nvars + 1, sizeof *goto_map);
-  temp_map = xnmalloc (nvars + 1, sizeof *temp_map);
-
   ngotos = 0;
   for (s = 0; s < nstates; ++s)
     {
@@ -132,16 +128,13 @@ set_goto_map (void)
 goto_number
 map_goto (state_number s0, symbol_number sym)
 {
-  goto_number high;
-  goto_number low;
-  goto_number middle;
-  state_number s;
-
-  low = goto_map[sym - ntokens];
-  high = goto_map[sym - ntokens + 1] - 1;
+  goto_number low = goto_map[sym - ntokens];
+  goto_number high = goto_map[sym - ntokens + 1] - 1;
 
   for (;;)
     {
+      goto_number middle;
+      state_number s;
       aver (low <= high);
       middle = (low + high) / 2;
       s = from_state[middle];
@@ -342,7 +335,7 @@ state_lookahead_tokens_count (state *s, bool default_reduction_only_for_accept)
   /* We need a lookahead either to distinguish different reductions
      (i.e., there are two or more), or to distinguish a reduction from a
      shift.  Otherwise, it is straightforward, and the state is
-     `consistent'.  However, do not treat a state with any reductions as
+     'consistent'.  However, do not treat a state with any reductions as
      consistent unless it is the accepting state (because there is never
      a lookahead token that makes sense there, and so no lookahead token
      should be read) if the user has otherwise disabled default
@@ -412,7 +405,6 @@ static void
 lookahead_tokens_print (FILE *out)
 {
   state_number i;
-  int j, k;
   fprintf (out, "Lookahead tokens: BEGIN\n");
   for (i = 0; i < nstates; ++i)
     {
@@ -421,21 +413,25 @@ lookahead_tokens_print (FILE *out)
       int n_lookahead_tokens = 0;
 
       if (reds->lookahead_tokens)
-        for (k = 0; k < reds->num; ++k)
-          if (reds->lookahead_tokens[k])
-            ++n_lookahead_tokens;
+        {
+          int j;
+          for (j = 0; j < reds->num; ++j)
+            if (reds->lookahead_tokens[j])
+              ++n_lookahead_tokens;
+        }
 
       fprintf (out, "State %d: %d lookahead tokens\n",
                i, n_lookahead_tokens);
 
       if (reds->lookahead_tokens)
-        for (j = 0; j < reds->num; ++j)
-          BITSET_FOR_EACH (iter, reds->lookahead_tokens[j], k, 0)
-          {
-            fprintf (out, "   on %d (%s) -> rule %d\n",
-                     k, symbols[k]->tag,
-                     reds->rules[j]->number);
-          };
+        {
+          int j, k;
+          for (j = 0; j < reds->num; ++j)
+            BITSET_FOR_EACH (iter, reds->lookahead_tokens[j], k, 0)
+              fprintf (out, "   on %d (%s) -> rule %d\n",
+                       k, symbols[k]->tag,
+                       reds->rules[j]->number);
+        }
     }
   fprintf (out, "Lookahead tokens: END\n");
 }

src/local.mk

@@ -111,7 +111,9 @@ BUILT_SOURCES +=                                \
 ## yacc.  ##
 ## ------ ##
 
-bin_SCRIPTS = $(YACC_SCRIPT)
+if ENABLE_YACC
+bin_SCRIPTS = src/yacc
+endif
 EXTRA_SCRIPTS = src/yacc
 MOSTLYCLEANFILES += src/yacc
 

src/location.c

@@ -96,10 +96,8 @@ location_compute (location *loc, boundary *cur, char const *token, size_t size)
 }
 
 
-/* Output to OUT the location LOC.
-   Warning: it uses quotearg's slot 3.  */
 unsigned
-location_print (FILE *out, location loc)
+location_print (location loc, FILE *out)
 {
   unsigned res = 0;
   int end_col = 0 != loc.end.column ? loc.end.column - 1 : 0;
@@ -161,7 +159,7 @@ cleanup_caret ()
 }
 
 void
-location_caret (FILE *out, location loc)
+location_caret (location loc, FILE *out)
 {
   /* FIXME: find a way to support multifile locations, and only open once each
      file. That would make the procedure future-proof.  */
@@ -190,7 +188,7 @@ location_caret (FILE *out, location loc)
   /* Read the actual line.  Don't update the offset, so that we keep a pointer
      to the start of the line.  */
   {
-    char c = getc (caret_info.source);
+    int c = getc (caret_info.source);
     if (c != EOF)
       {
         /* Quote the file, indent by a single column.  */
@@ -221,7 +219,7 @@ void
 boundary_set_from_string (boundary *bound, char *loc_str)
 {
   /* Must search in reverse since the file name field may
-   * contain `.' or `:'.  */
+   * contain '.' or ':'.  */
   char *delim = strrchr (loc_str, '.');
   aver (delim);
   *delim = '\0';

src/location.h

@@ -20,6 +20,10 @@
 #ifndef LOCATION_H_
 # define LOCATION_H_
 
+# include <stdbool.h>
+# include <stdio.h>
+# include <string.h> /* strcmp */
+
 # include "uniqstr.h"
 
 /* A boundary between two characters.  */
@@ -98,16 +102,17 @@ extern location const empty_location;
 void location_compute (location *loc,
                        boundary *cur, char const *token, size_t size);
 
-/* Print location to file. Return number of actually printed
-   characters.  */
-unsigned location_print (FILE *out, location loc);
+/* Print location to file.
+   Return number of actually printed characters.
+   Warning: uses quotearg's slot 3. */
+unsigned location_print (location loc, FILE *out);
 
 /* Free any allocated ressources and close any open file handles that are
    left-over by the usage of location_caret.  */
 void cleanup_caret (void);
 
 /* Output to OUT the line and caret corresponding to location LOC.  */
-void location_caret (FILE *out, location loc);
+void location_caret (location loc, FILE *out);
 
 /* Return -1, 0, 1, depending whether a is before, equal, or
    after b.  */
@@ -120,7 +125,7 @@ location_cmp (location a, location b)
   return res;
 }
 
-/* LOC_STR must be formatted as `file:line.column', it will be modified.  */
+/* LOC_STR must be formatted as 'file:line.column', it will be modified.  */
 void boundary_set_from_string (boundary *bound, char *loc_str);
 
 #endif /* ! defined LOCATION_H_ */

src/main.c

@@ -76,6 +76,7 @@ main (int argc, char *argv[])
 
   uniqstrs_new ();
   muscle_init ();
+  complain_init ();
 
   getargs (argc, argv);
 
@@ -146,8 +147,6 @@ main (int argc, char *argv[])
 
   print_precedence_warnings ();
 
-  print_assoc_warnings ();
-
   /* Output file names. */
   compute_output_file_names ();
 

src/muscle-tab.c

@@ -28,6 +28,31 @@
 #include "muscle-tab.h"
 #include "quote.h"
 
+muscle_kind
+muscle_kind_new (char const *k)
+{
+  if (STREQ (k, "code"))
+    return muscle_code;
+  else if (STREQ (k, "keyword"))
+    return muscle_keyword;
+  else if (STREQ (k, "string"))
+    return muscle_string;
+  aver (0);
+}
+
+char const *
+muscle_kind_string (muscle_kind k)
+{
+  switch (k)
+    {
+    case muscle_code:    return "code";
+    case muscle_keyword: return "keyword";
+    case muscle_string:  return "string";
+    }
+  aver (0);
+}
+
+
 /* A key-value pair, along with storage that can be reclaimed when
    this pair is no longer needed.  */
 typedef struct
@@ -35,8 +60,21 @@ typedef struct
   char const *key;
   char const *value;
   char *storage;
+  muscle_kind kind;
 } muscle_entry;
 
+
+/* The name of muscle for the %define variable VAR (corresponding to
+   FIELD, if defined).  */
+static uniqstr
+muscle_name (char const *var, char const *field)
+{
+  if (field)
+    return UNIQSTR_CONCAT ("percent_define_", field, "(", var, ")");
+  else
+    return UNIQSTR_CONCAT ("percent_define(", var, ")");
+}
+
 /* An obstack used to create some entries.  */
 struct obstack muscle_obstack;
 
@@ -60,10 +98,18 @@ hash_muscle (const void *x, size_t tablesize)
   return hash_string (m->key, tablesize);
 }
 
-/*-----------------------------------------------------------------.
-| Create the MUSCLE_TABLE, and initialize it with default values.  |
-| Also set up the MUSCLE_OBSTACK.                                  |
-`-----------------------------------------------------------------*/
+/* Create a fresh muscle name KEY, and insert in the hash table.  */
+static void *
+muscle_entry_new (char const *key)
+{
+  muscle_entry *res = xmalloc (sizeof *res);
+  res->key = key;
+  res->value = NULL;
+  res->storage = NULL;
+  if (!hash_insert (muscle_table, res))
+    xalloc_die ();
+  return res;
+}
 
 static void
 muscle_entry_free (void *entry)
@@ -87,10 +133,6 @@ muscle_init (void)
 }
 
 
-/*------------------------------------------------------------.
-| Free all the memory consumed by the muscle machinery only.  |
-`------------------------------------------------------------*/
-
 void
 muscle_free (void)
 {
@@ -98,71 +140,64 @@ muscle_free (void)
   obstack_free (&muscle_obstack, NULL);
 }
 
+/* Look for the muscle named KEY.  Return NULL if does not exist.  */
+static
+muscle_entry *
+muscle_lookup (char const *key)
+{
+  muscle_entry probe;
+  probe.key = key;
+  return hash_lookup (muscle_table, &probe);
+}
 
 
-/*------------------------------------------------------------.
-| Insert (KEY, VALUE).  If KEY already existed, overwrite the |
-| previous value.                                             |
-`------------------------------------------------------------*/
-
 void
 muscle_insert (char const *key, char const *value)
 {
-  muscle_entry probe;
-  muscle_entry *entry;
-
-  probe.key = key;
-  entry = hash_lookup (muscle_table, &probe);
-
-  if (!entry)
-    {
-      /* First insertion in the hash. */
-      entry = xmalloc (sizeof *entry);
-      entry->key = key;
-      if (!hash_insert (muscle_table, entry))
-        xalloc_die ();
-    }
-  else
+  muscle_entry *entry = muscle_lookup (key);
+  if (entry)
     free (entry->storage);
+  else
+    /* First insertion in the hash. */
+    entry = muscle_entry_new (key);
   entry->value = value;
   entry->storage = NULL;
 }
 
 
-/*-------------------------------------------------------------------.
-| Append VALUE to the current value of KEY.  If KEY did not already  |
-| exist, create it.  Use MUSCLE_OBSTACK.  De-allocate the previously |
-| associated value.  Copy VALUE and SEPARATOR.                       |
-`-------------------------------------------------------------------*/
+/* Append VALUE to the current value of KEY.  If KEY did not already
+   exist, create it.  Use MUSCLE_OBSTACK.  De-allocate the previously
+   associated value.  Copy VALUE and SEPARATOR.  If VALUE does not end
+   with TERMINATOR, append one.  */
 
-void
-muscle_grow (const char *key, const char *val, const char *separator)
+static void
+muscle_grow (const char *key, const char *val,
+             const char *separator, const char *terminator)
 {
-  muscle_entry probe;
-  muscle_entry *entry = NULL;
+  muscle_entry *entry = muscle_lookup (key);
+  size_t vals = strlen (val);
+  size_t terms = strlen (terminator);
 
-  probe.key = key;
-  entry = hash_lookup (muscle_table, &probe);
-
-  if (!entry)
+  if (entry)
     {
-      /* First insertion in the hash. */
-      entry = xmalloc (sizeof *entry);
-      entry->key = key;
-      if (!hash_insert (muscle_table, entry))
-        xalloc_die ();
-      entry->value = entry->storage = xstrdup (val);
+      obstack_sgrow (&muscle_obstack, entry->value);
+      obstack_sgrow (&muscle_obstack, separator);
+      free (entry->storage);
     }
   else
-    {
-      /* Grow the current value. */
-      char *new_val;
-      obstack_printf (&muscle_obstack, "%s%s%s", entry->value, separator, val);
-      free (entry->storage);
-      new_val = obstack_finish0 (&muscle_obstack);
-      entry->value = entry->storage = xstrdup (new_val);
-      obstack_free (&muscle_obstack, new_val);
-    }
+    entry = muscle_entry_new (key);
+
+  obstack_sgrow (&muscle_obstack, val);
+
+  if (terms <= vals
+      && STRNEQ (val + vals - terms, terminator))
+    obstack_sgrow (&muscle_obstack, terminator);
+
+  {
+    char *new_val = obstack_finish0 (&muscle_obstack);
+    entry->value = entry->storage = xstrdup (new_val);
+    obstack_free (&muscle_obstack, new_val);
+  }
 }
 
 /*------------------------------------------------------------------.
@@ -179,7 +214,7 @@ muscle_syncline_grow (char const *key, location loc)
                  quotearg_style (c_quoting_style, loc.start.file));
   obstack_sgrow (&muscle_obstack, ")[");
   extension = obstack_finish0 (&muscle_obstack);
-  muscle_grow (key, extension, "");
+  muscle_grow (key, extension, "", "");
   obstack_free (&muscle_obstack, extension);
 }
 
@@ -193,12 +228,13 @@ void
 muscle_code_grow (const char *key, const char *val, location loc)
 {
   muscle_syncline_grow (key, loc);
-  muscle_grow (key, val, "\n");
+  muscle_grow (key, val, "\n", "\n");
 }
 
 
-void muscle_pair_list_grow (const char *muscle,
-                            const char *a1, const char *a2)
+void
+muscle_pair_list_grow (const char *muscle,
+                       const char *a1, const char *a2)
 {
   char *pair;
   obstack_sgrow (&muscle_obstack, "[");
@@ -207,54 +243,33 @@ void muscle_pair_list_grow (const char *muscle,
   obstack_quote (&muscle_obstack, a2);
   obstack_sgrow (&muscle_obstack, "]");
   pair = obstack_finish0 (&muscle_obstack);
-  muscle_grow (muscle, pair, ",\n");
+  muscle_grow (muscle, pair, ",\n", "");
   obstack_free (&muscle_obstack, pair);
 }
 
 
-/*----------------------------------------------------------------------------.
-| Find the value of muscle KEY.  Unlike MUSCLE_FIND, this is always reliable  |
-| to determine whether KEY has a value.                                       |
-`----------------------------------------------------------------------------*/
-
 char const *
 muscle_find_const (char const *key)
 {
-  muscle_entry probe;
-  muscle_entry *result = NULL;
-
-  probe.key = key;
-  result = hash_lookup (muscle_table, &probe);
-  if (result)
-    return result->value;
-  return NULL;
+  muscle_entry *entry = muscle_lookup (key);
+  return entry ? entry->value : NULL;
 }
 
 
-/*----------------------------------------------------------------------------.
-| Find the value of muscle KEY.  Abort if muscle_insert was invoked more      |
-| recently than muscle_grow for KEY since muscle_find can't return a          |
-| char const *.                                                               |
-`----------------------------------------------------------------------------*/
-
 char *
 muscle_find (char const *key)
 {
-  muscle_entry probe;
-  muscle_entry *result = NULL;
-
-  probe.key = key;
-  result = hash_lookup (muscle_table, &probe);
-  if (result)
+  muscle_entry *entry = muscle_lookup (key);
+  if (entry)
     {
-      aver (result->value == result->storage);
-      return result->storage;
+      aver (entry->value == entry->storage);
+      return entry->storage;
     }
   return NULL;
 }
 
 
-/* In the format `file_name:line.column', append BOUND to MUSCLE.  Use
+/* In the format 'file_name:line.column', append BOUND to MUSCLE.  Use
    digraphs for special characters in the file name.  */
 
 static void
@@ -265,12 +280,12 @@ muscle_boundary_grow (char const *key, boundary bound)
   obstack_escape (&muscle_obstack, bound.file);
   obstack_printf (&muscle_obstack, ":%d.%d]]", bound.line, bound.column);
   extension = obstack_finish0 (&muscle_obstack);
-  muscle_grow (key, extension, "");
+  muscle_grow (key, extension, "", "");
   obstack_free (&muscle_obstack, extension);
 }
 
 
-/* In the format `[[file_name:line.column]], [[file_name:line.column]]',
+/* In the format '[[file_name:line.column]], [[file_name:line.column]]',
    append LOC to MUSCLE.  Use digraphs for special characters in each
    file name.  */
 
@@ -278,14 +293,15 @@ static void
 muscle_location_grow (char const *key, location loc)
 {
   muscle_boundary_grow (key, loc.start);
-  muscle_grow (key, "", ", ");
+  muscle_grow (key, "", ", ", "");
   muscle_boundary_grow (key, loc.end);
 }
 
 #define COMMON_DECODE(Value)                                    \
   case '$':                                                     \
-    aver (*++(Value) == ']');                                   \
-    aver (*++(Value) == '[');                                   \
+    ++(Value); aver (*(Value) == '[');                          \
+    ++(Value); aver (*(Value) == ']');                          \
+    ++(Value); aver (*(Value) == '[');                          \
     obstack_sgrow (&muscle_obstack, "$");                       \
     break;                                                      \
   case '@':                                                     \
@@ -329,13 +345,12 @@ string_decode (char const *key)
 
 /* Reverse of muscle_location_grow.  */
 static location
-location_decode (char const *key)
+location_decode (char const *value)
 {
   location loc;
-  char const *value = muscle_find_const (key);
   aver (value);
   aver (*value == '[');
-  aver (*++value == '[');
+  ++value; aver (*value == '[');
   while (*++value)
     switch (*value)
       {
@@ -346,16 +361,16 @@ location_decode (char const *key)
         case ']':
           {
             char *boundary_str;
-            aver (*++value == ']');
+            ++value; aver (*value == ']');
             boundary_str = obstack_finish0 (&muscle_obstack);
             switch (*++value)
               {
                 case ',':
                   boundary_set_from_string (&loc.start, boundary_str);
                   obstack_free (&muscle_obstack, boundary_str);
-                  aver (*++value == ' ');
-                  aver (*++value == '[');
-                  aver (*++value == '[');
+                  ++value; aver (*value == ' ');
+                  ++value; aver (*value == '[');
+                  ++value; aver (*value == '[');
                   break;
                 case '\0':
                   boundary_set_from_string (&loc.end, boundary_str);
@@ -377,11 +392,11 @@ void
 muscle_user_name_list_grow (char const *key, char const *user_name,
                             location loc)
 {
-  muscle_grow (key, "[[[[", ",");
-  muscle_grow (key, user_name, "");
-  muscle_grow (key, "]], ", "");
+  muscle_grow (key, "[[[[", ",", "");
+  muscle_grow (key, user_name, "", "");
+  muscle_grow (key, "]], ", "", "");
   muscle_location_grow (key, loc);
-  muscle_grow (key, "]]", "");
+  muscle_grow (key, "]]", "", "");
 }
 
 
@@ -475,16 +490,17 @@ muscle_percent_variable_update (char const *variable, location variable_loc,
 
 void
 muscle_percent_define_insert (char const *var, location variable_loc,
+                              muscle_kind kind,
                               char const *value,
                               muscle_percent_define_how how)
 {
   /* Backward compatibility.  */
   char *variable = muscle_percent_variable_update (var, variable_loc, &value);
-  char const *name = UNIQSTR_CONCAT ("percent_define(", variable, ")");
-  char const *loc_name = UNIQSTR_CONCAT ("percent_define_loc(", variable, ")");
-  char const *syncline_name =
-    UNIQSTR_CONCAT ("percent_define_syncline(", variable, ")");
-  char const *how_name = UNIQSTR_CONCAT ("percent_define_how(", variable, ")");
+  uniqstr name = muscle_name (variable, NULL);
+  uniqstr loc_name = muscle_name (variable, "loc");
+  uniqstr syncline_name = muscle_name (variable, "syncline");
+  uniqstr how_name = muscle_name (variable, "how");
+  uniqstr kind_name = muscle_name (variable, "kind");
 
   /* Command-line options are processed before the grammar file.  */
   if (how == MUSCLE_PERCENT_DEFINE_GRAMMAR_FILE
@@ -510,6 +526,7 @@ muscle_percent_define_insert (char const *var, location variable_loc,
   muscle_user_name_list_grow ("percent_define_user_variables", variable,
                               variable_loc);
   MUSCLE_INSERT_INT (how_name, how);
+  MUSCLE_INSERT_STRING (kind_name, muscle_kind_string (kind));
  end:
   free (variable);
 }
@@ -520,85 +537,120 @@ void
 muscle_percent_define_ensure (char const *variable, location loc,
                               bool value)
 {
+  uniqstr name = muscle_name (variable, NULL);
   char const *val = value ? "" : "false";
-  char const *name = UNIQSTR_CONCAT ("percent_define(", variable, ")");
 
-  /* %pure-parser is deprecated in favor of `%define api.pure', so use
-     `%define api.pure' in a backward-compatible manner here.  First,
-     don't complain if %pure-parser is specified multiple times.  */
-  if (!muscle_find_const (name))
-    muscle_percent_define_insert (variable, loc, val,
-                                  MUSCLE_PERCENT_DEFINE_GRAMMAR_FILE);
-  /* In all cases, use api.pure now so that the backend doesn't complain if
-     the skeleton ignores api.pure, but do warn now if there's a previous
-     conflicting definition from an actual %define.  */
-  if (muscle_percent_define_flag_if (variable) != value)
-    muscle_percent_define_insert (variable, loc, val,
+  /* Don't complain is VARIABLE is already defined, but be sure to set
+     its value to VAL.  */
+  if (!muscle_find_const (name)
+      || muscle_percent_define_flag_if (variable) != value)
+    muscle_percent_define_insert (variable, loc, muscle_keyword, val,
                                   MUSCLE_PERCENT_DEFINE_GRAMMAR_FILE);
 }
 
+/* Mark %define VARIABLE as used.  */
+static void
+muscle_percent_define_use (char const *variable)
+{
+  muscle_insert (muscle_name (variable, "bison_variables"), "");
+}
+
+/* The value of %define variable VARIABLE (corresponding to FIELD, if
+   defined).  Do not register as used, but diagnose unset variables.  */
+
+static
+char const *
+muscle_percent_define_get_raw (char const *variable, char const *field)
+{
+  uniqstr name = muscle_name (variable, field);
+  char const *res = muscle_find_const (name);
+  if (!res)
+    complain (NULL, fatal, _("%s: undefined %%define variable %s"),
+              "muscle_percent_define_get_raw", quote (variable));
+  return res;
+}
+
 char *
 muscle_percent_define_get (char const *variable)
 {
-  char const *name = UNIQSTR_CONCAT ("percent_define(", variable, ")");
-  char const *usage_name =
-    UNIQSTR_CONCAT ("percent_define_bison_variables(", variable, ")");
+  uniqstr name = muscle_name (variable, NULL);
   char *value = string_decode (name);
   if (!value)
     value = xstrdup ("");
-
-  muscle_insert (usage_name, "");
+  muscle_percent_define_use (variable);
   return value;
 }
 
+/* The kind of VARIABLE.  An error if undefined.  */
+static muscle_kind
+muscle_percent_define_get_kind (char const *variable)
+{
+  return muscle_kind_new (muscle_percent_define_get_raw (variable, "kind"));
+}
+
+/* Check the kind of VARIABLE.  An error if undefined.  */
+static void
+muscle_percent_define_check_kind (char const *variable, muscle_kind kind)
+{
+  if (muscle_percent_define_get_kind (variable) != kind)
+    {
+      location loc = muscle_percent_define_get_loc (variable);
+      switch (kind)
+        {
+        case muscle_code:
+          complain (&loc, Wdeprecated,
+                    "%%define variable '%s' requires '{...}' values",
+                    variable);
+          break;
+        case muscle_keyword:
+          complain (&loc, Wdeprecated,
+                    "%%define variable '%s' requires keyword values",
+                    variable);
+          break;
+        case muscle_string:
+          complain (&loc, Wdeprecated,
+                    "%%define variable '%s' requires '\"...\"' values",
+                    variable);
+          break;
+        }
+    }
+}
+
+
 location
 muscle_percent_define_get_loc (char const *variable)
 {
-  char const *loc_name = UNIQSTR_CONCAT ("percent_define_loc(", variable, ")");
-  if (!muscle_find_const (loc_name))
-    complain (NULL, fatal, _("%s: undefined %%define variable %s"),
-              "muscle_percent_define_get_loc", quote (variable));
-  return location_decode (loc_name);
+  return location_decode (muscle_percent_define_get_raw (variable, "loc"));
 }
 
 char const *
 muscle_percent_define_get_syncline (char const *variable)
 {
-  char const *syncline_name =
-    UNIQSTR_CONCAT ("percent_define_syncline(", variable, ")");
-  char const *syncline = muscle_find_const (syncline_name);
-  if (!syncline)
-    complain (NULL, fatal, _("%s: undefined %%define variable %s"),
-              "muscle_percent_define_get_syncline", quote (variable));
-  return syncline;
+  return muscle_percent_define_get_raw (variable, "syncline");
 }
 
 bool
 muscle_percent_define_ifdef (char const *variable)
 {
-  char const *name = UNIQSTR_CONCAT ("percent_define(", variable, ")");
-  char const *usage_name =
-    UNIQSTR_CONCAT ("percent_define_bison_variables(", variable, ")");
-  char const *value = muscle_find_const (name);
-  if (value)
+  if (muscle_find_const (muscle_name (variable, NULL)))
     {
-      muscle_insert (usage_name, "");
+      muscle_percent_define_use (variable);
       return true;
     }
-
-  return false;
+  else
+    return false;
 }
 
 bool
 muscle_percent_define_flag_if (char const *variable)
 {
-  char const *invalid_boolean_name =
-    UNIQSTR_CONCAT ("percent_define_invalid_boolean(", variable, ")");
+  uniqstr invalid_boolean_name = muscle_name (variable, "invalid_boolean");
   bool result = false;
 
   if (muscle_percent_define_ifdef (variable))
     {
       char *value = muscle_percent_define_get (variable);
+      muscle_percent_define_check_kind (variable, muscle_keyword);
       if (value[0] == '\0' || STREQ (value, "true"))
         result = true;
       else if (STREQ (value, "false"))
@@ -623,20 +675,21 @@ muscle_percent_define_flag_if (char const *variable)
 void
 muscle_percent_define_default (char const *variable, char const *value)
 {
-  char const *name = UNIQSTR_CONCAT ("percent_define(", variable, ")");
-  char const *loc_name = UNIQSTR_CONCAT ("percent_define_loc(", variable, ")");
-  char const *syncline_name =
-    UNIQSTR_CONCAT ("percent_define_syncline(", variable, ")");
+  uniqstr name = muscle_name (variable, NULL);
   if (!muscle_find_const (name))
     {
-      location loc;
       MUSCLE_INSERT_STRING (name, value);
-      loc.start.file = loc.end.file = "<default value>";
-      loc.start.line = loc.end.line = -1;
-      loc.start.column = loc.end.column = -1;
-      muscle_insert (loc_name, "");
-      muscle_location_grow (loc_name, loc);
-      muscle_insert (syncline_name, "");
+      MUSCLE_INSERT_STRING (muscle_name (variable, "kind"), "keyword");
+      {
+        uniqstr loc_name = muscle_name (variable, "loc");
+        location loc;
+        loc.start.file = loc.end.file = "<default value>";
+        loc.start.line = loc.end.line = -1;
+        loc.start.column = loc.end.column = -1;
+        muscle_insert (loc_name, "");
+        muscle_location_grow (loc_name, loc);
+      }
+      muscle_insert (muscle_name (variable, "syncline"), "");
     }
 }
 
@@ -646,8 +699,9 @@ muscle_percent_define_check_values (char const * const *values)
   for (; *values; ++values)
     {
       char const * const *variablep = values;
-      char const *name = UNIQSTR_CONCAT ("percent_define(", *variablep, ")");
+      uniqstr name = muscle_name (*variablep, NULL);
       char *value = string_decode (name);
+      muscle_percent_define_check_kind (*variablep, muscle_keyword);
       if (value)
         {
           for (++values; *values; ++values)
@@ -664,7 +718,7 @@ muscle_percent_define_check_values (char const * const *values)
                                quote (*variablep), quote_n (1, value));
               i += SUB_INDENT;
               for (values = variablep + 1; *values; ++values)
-                complain_indent (&loc, complaint | no_caret, &i,
+                complain_indent (&loc, complaint | no_caret | silent, &i,
                                  _("accepted value: %s"), quote (*values));
             }
           else
@@ -711,11 +765,6 @@ muscle_m4_output_processor (void *entry, void *out)
 }
 
 
-/*----------------------------------------------------------------.
-| Output the definition of all the current muscles into a list of |
-| m4_defines.                                                     |
-`----------------------------------------------------------------*/
-
 void
 muscles_m4_output (FILE *out)
 {

src/muscle-tab.h

@@ -24,10 +24,41 @@
 
 # include "location.h"
 
+/* The kind of value associated to this muscle, depending on the
+   syntax of the value: keyword (no delimiter, e.g., true), string
+   (double quotes, e.g., "foo.h"), or code (braces, e.g., {int}).  */
+typedef enum
+{
+  muscle_code,
+  muscle_keyword,
+  muscle_string
+} muscle_kind;
+
+/* Conversion from string.  */
+muscle_kind muscle_kind_new (char const *k);
+
+/* Conversion to string.  */
+char const *muscle_kind_string (muscle_kind k);
+
+
+/* Create the MUSCLE_TABLE, and initialize it with default values.
+   Also set up the MUSCLE_OBSTACK.  */
 void muscle_init (void);
+
+/* Insert (KEY, VALUE).  If KEY already existed, overwrite the
+   previous value.  Otherwise create as a muscle_string type.  */
 void muscle_insert (char const *key, char const *value);
+
+/* Find the value of muscle KEY.  Unlike MUSCLE_FIND, this is always
+   reliable to determine whether KEY has a value.  */
 char const *muscle_find_const (char const *key);
+
+/* Find the value of muscle KEY.  Abort if muscle_insert was invoked
+   more recently than muscle_grow for KEY since muscle_find can't
+   return a char const *.  */
 char *muscle_find (char const *key);
+
+/* Free all the memory consumed by the muscle machinery only.  */
 void muscle_free (void);
 
 
@@ -47,14 +78,14 @@ extern struct obstack muscle_obstack;
   } while (0)
 
 # define MUSCLE_INSERT_INT(Key, Value)          \
-  MUSCLE_INSERTF(Key, "%d", Value)
+  MUSCLE_INSERTF (Key, "%d", Value)
 
 # define MUSCLE_INSERT_LONG_INT(Key, Value)     \
-  MUSCLE_INSERTF(Key, "%ld", Value)
+  MUSCLE_INSERTF (Key, "%ld", Value)
 
 /* Key -> Value, but don't apply escaping to Value. */
 # define MUSCLE_INSERT_STRING_RAW(Key, Value)   \
-  MUSCLE_INSERTF(Key, "%s", Value)
+  MUSCLE_INSERTF (Key, "%s", Value)
 
 /* Key -> Value, applying M4 escaping to Value. */
 # define MUSCLE_INSERT_STRING(Key, Value)                       \
@@ -63,23 +94,14 @@ extern struct obstack muscle_obstack;
     muscle_insert (Key, obstack_finish0 (&muscle_obstack));     \
   } while (0)
 
+/* Key -> Value, applying C escaping to Value (and then M4). */
 # define MUSCLE_INSERT_C_STRING(Key, Value)                     \
-  do {                                                          \
-    obstack_escape (&muscle_obstack,                            \
-                    quotearg_style (c_quoting_style, Value));   \
-    muscle_insert (Key, obstack_finish0 (&muscle_obstack));     \
-  } while (0)
-
-/* Append VALUE to the current value of KEY.  If KEY did not already
-   exist, create it.  Use MUSCLE_OBSTACK.  De-allocate the previously
-   associated value.  Copy VALUE and SEPARATOR.  */
-
-void muscle_grow (const char *key, const char *value, const char *separator);
+  MUSCLE_INSERT_STRING (Key, quotearg_style (c_quoting_style, Value))
 
 
 /* Append VALUE to the current value of KEY, using muscle_grow.  But
-   in addition, issue a synchronization line for the location LOC.  */
-
+   in addition, issue a synchronization line for the location LOC.
+   Be sure to append on a new line.  */
 void muscle_code_grow (const char *key, const char *value, location loc);
 
 
@@ -92,14 +114,15 @@ void muscle_pair_list_grow (const char *muscle,
 
 /* Grow KEY for the occurrence of the name USER_NAME at LOC appropriately for
    use with b4_check_user_names in ../data/bison.m4.  USER_NAME is not escaped
-   with digraphs, so it must not contain `[' or `]'.  */
+   with digraphs, so it must not contain '[' or ']'.  */
 void muscle_user_name_list_grow (char const *key, char const *user_name,
                                  location loc);
 
 /* Indicates whether a variable's value was specified with -D/--define, with
    -F/--force-define, or in the grammar file.  */
 typedef enum {
-  MUSCLE_PERCENT_DEFINE_D = 0, MUSCLE_PERCENT_DEFINE_F,
+  MUSCLE_PERCENT_DEFINE_D = 0,
+  MUSCLE_PERCENT_DEFINE_F,
   MUSCLE_PERCENT_DEFINE_GRAMMAR_FILE
 } muscle_percent_define_how;
 
@@ -113,6 +136,7 @@ typedef enum {
    this as a user occurrence of VARIABLE by invoking
    muscle_user_name_list_grow.  */
 void muscle_percent_define_insert (char const *variable, location variable_loc,
+                                   muscle_kind kind,
                                    char const *value,
                                    muscle_percent_define_how how);
 
@@ -186,6 +210,8 @@ void muscle_percent_define_check_values (char const * const *values);
 void muscle_percent_code_grow (char const *qualifier, location qualifier_loc,
                                char const *code, location code_loc);
 
+/* Output the definition of all the current muscles into a list of
+   m4_defines.  */
 void muscles_m4_output (FILE *out);
 
 #endif /* not MUSCLE_TAB_H_ */

src/output.c

@@ -90,20 +90,19 @@ Name (char const *name,                                                 \
                                                                         \
   lmin = min;                                                           \
   lmax = max;                                                           \
-  /* Build `NAME_min' and `NAME_max' in the obstack. */                 \
+  /* Build 'NAME_min' and 'NAME_max' in the obstack. */                 \
   obstack_printf (&format_obstack, "%s_min", name);                     \
   MUSCLE_INSERT_LONG_INT (obstack_finish0 (&format_obstack), lmin);     \
   obstack_printf (&format_obstack, "%s_max", name);                     \
   MUSCLE_INSERT_LONG_INT (obstack_finish0 (&format_obstack), lmax);     \
 }
 
-GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_unsigned_int_table, unsigned int)
-GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_int_table, int)
-GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_base_table, base_number)
-GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_rule_number_table, rule_number)
-GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_symbol_number_table, symbol_number)
-GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_state_number_table, state_number)
-
+GENERATE_MUSCLE_INSERT_TABLE (muscle_insert_unsigned_int_table, unsigned int)
+GENERATE_MUSCLE_INSERT_TABLE (muscle_insert_int_table, int)
+GENERATE_MUSCLE_INSERT_TABLE (muscle_insert_base_table, base_number)
+GENERATE_MUSCLE_INSERT_TABLE (muscle_insert_rule_number_table, rule_number)
+GENERATE_MUSCLE_INSERT_TABLE (muscle_insert_symbol_number_table, symbol_number)
+GENERATE_MUSCLE_INSERT_TABLE (muscle_insert_state_number_table, state_number)
 
 /*----------------------------------------------------------------.
 | Print to OUT a representation of CP quoted and escaped for M4.  |
@@ -227,7 +226,7 @@ prepare_rules (void)
       /* LHS of the rule R. */
       r1[r] = rules[r].lhs->number;
       /* Length of rule R's RHS. */
-      r2[r] = rule_rhs_length(&rules[r]);
+      r2[r] = rule_rhs_length (&rules[r]);
       /* Line where rule was defined. */
       rline[r] = rules[r].location.start.line;
       /* Dynamic precedence (GLR).  */
@@ -417,31 +416,31 @@ prepare_symbol_definitions (void)
 
       /* Whether the symbol has an identifier.  */
       value = symbol_id_get (sym);
-      SET_KEY("has_id");
+      SET_KEY ("has_id");
       MUSCLE_INSERT_INT (key, !!value);
 
       /* Its identifier.  */
-      SET_KEY("id");
+      SET_KEY ("id");
       MUSCLE_INSERT_STRING (key, value ? value : "");
 
       /* Its tag.  Typically for documentation purpose.  */
-      SET_KEY("tag");
+      SET_KEY ("tag");
       MUSCLE_INSERT_STRING (key, sym->tag);
 
-      SET_KEY("user_number");
+      SET_KEY ("user_number");
       MUSCLE_INSERT_INT (key, sym->user_token_number);
 
-      SET_KEY("is_token");
+      SET_KEY ("is_token");
       MUSCLE_INSERT_INT (key,
                          i < ntokens && sym != errtoken && sym != undeftoken);
 
-      SET_KEY("number");
+      SET_KEY ("number");
       MUSCLE_INSERT_INT (key, sym->number);
 
-      SET_KEY("has_type");
+      SET_KEY ("has_type");
       MUSCLE_INSERT_INT (key, !!sym->type_name);
 
-      SET_KEY("type");
+      SET_KEY ("type");
       MUSCLE_INSERT_STRING (key, sym->type_name ? sym->type_name : "");
 
       {
@@ -451,18 +450,18 @@ prepare_symbol_definitions (void)
             /* "printer", not "%printer".  */
             char const *pname = code_props_type_string (j) + 1;
             code_props const *p = symbol_code_props_get (sym, j);
-            SET_KEY2("has", pname);
+            SET_KEY2 ("has", pname);
             MUSCLE_INSERT_INT (key, !!p->code);
 
             if (p->code)
               {
-                SET_KEY2(pname, "file");
+                SET_KEY2 (pname, "file");
                 MUSCLE_INSERT_STRING (key, p->location.start.file);
 
-                SET_KEY2(pname, "line");
+                SET_KEY2 (pname, "line");
                 MUSCLE_INSERT_INT (key, p->location.start.line);
 
-                SET_KEY(pname);
+                SET_KEY (pname);
                 MUSCLE_INSERT_STRING_RAW (key, p->code);
               }
           }
@@ -705,6 +704,11 @@ output (void)
   /* Process the selected skeleton file.  */
   output_skeleton ();
 
+  /* If late errors were generated, destroy the generated source
+     files. */
+  if (complaint_status)
+    unlink_generated_sources ();
+
   obstack_free (&format_obstack, NULL);
 }
 

src/parse-gram.h

@@ -1,4 +1,4 @@
-/* A Bison parser, made by GNU Bison 2.7.1021-bb417-dirty.  */
+/* A Bison parser, made by GNU Bison 3.0.  */
 
 /* Bison interface for Yacc-like parsers in C
 
@@ -48,10 +48,12 @@
 extern int gram_debug;
 #endif
 /* "%code requires" blocks.  */
-#line 223 "src/parse-gram.y" /* yacc.c:1932  */
+#line 21 "src/parse-gram.y" /* yacc.c:1909  */
+
+  #include "symlist.h"
+  #include "symtab.h"
+#line 221 "src/parse-gram.y" /* yacc.c:1909  */
 
-# ifndef PARAM_TYPE
-#  define PARAM_TYPE
   typedef enum
   {
     param_none   = 0,
@@ -59,10 +61,10 @@ extern int gram_debug;
     param_parse  = 1 << 1,
     param_both   = param_lex | param_parse
   } param_type;
-# endif
+#line 645 "src/parse-gram.y" /* yacc.c:1909  */
+#include "muscle-tab.h"
 
-
-#line 66 "src/parse-gram.h" /* yacc.c:1932  */
+#line 68 "src/parse-gram.h" /* yacc.c:1909  */
 
 /* Token type.  */
 #ifndef GRAM_TOKENTYPE
@@ -71,143 +73,97 @@ extern int gram_debug;
   {
     GRAM_EOF = 0,
     STRING = 258,
-    INT = 259,
-    PERCENT_TOKEN = 260,
-    PERCENT_NTERM = 261,
-    PERCENT_TYPE = 262,
-    PERCENT_DESTRUCTOR = 263,
-    PERCENT_PRINTER = 264,
-    PERCENT_LEFT = 265,
-    PERCENT_RIGHT = 266,
-    PERCENT_NONASSOC = 267,
-    PERCENT_PRECEDENCE = 268,
-    PERCENT_PREC = 269,
-    PERCENT_DPREC = 270,
-    PERCENT_MERGE = 271,
-    PERCENT_CODE = 272,
-    PERCENT_DEFAULT_PREC = 273,
-    PERCENT_DEFINE = 274,
-    PERCENT_DEFINES = 275,
-    PERCENT_ERROR_VERBOSE = 276,
-    PERCENT_EXPECT = 277,
-    PERCENT_EXPECT_RR = 278,
-    PERCENT_FLAG = 279,
-    PERCENT_FILE_PREFIX = 280,
-    PERCENT_GLR_PARSER = 281,
-    PERCENT_INITIAL_ACTION = 282,
-    PERCENT_LANGUAGE = 283,
-    PERCENT_NAME_PREFIX = 284,
-    PERCENT_NO_DEFAULT_PREC = 285,
-    PERCENT_NO_LINES = 286,
-    PERCENT_NONDETERMINISTIC_PARSER = 287,
-    PERCENT_OUTPUT = 288,
-    PERCENT_REQUIRE = 289,
-    PERCENT_SKELETON = 290,
-    PERCENT_START = 291,
-    PERCENT_TOKEN_TABLE = 292,
-    PERCENT_VERBOSE = 293,
-    PERCENT_YACC = 294,
-    BRACED_CODE = 295,
-    BRACED_PREDICATE = 296,
-    BRACKETED_ID = 297,
-    CHAR = 298,
-    EPILOGUE = 299,
-    EQUAL = 300,
-    ID = 301,
-    ID_COLON = 302,
-    PERCENT_PERCENT = 303,
-    PIPE = 304,
-    PROLOGUE = 305,
-    SEMICOLON = 306,
-    TAG = 307,
-    TAG_ANY = 308,
-    TAG_NONE = 309,
+    PERCENT_TOKEN = 259,
+    PERCENT_NTERM = 260,
+    PERCENT_TYPE = 261,
+    PERCENT_DESTRUCTOR = 262,
+    PERCENT_PRINTER = 263,
+    PERCENT_LEFT = 264,
+    PERCENT_RIGHT = 265,
+    PERCENT_NONASSOC = 266,
+    PERCENT_PRECEDENCE = 267,
+    PERCENT_PREC = 268,
+    PERCENT_DPREC = 269,
+    PERCENT_MERGE = 270,
+    PERCENT_CODE = 271,
+    PERCENT_DEFAULT_PREC = 272,
+    PERCENT_DEFINE = 273,
+    PERCENT_DEFINES = 274,
+    PERCENT_ERROR_VERBOSE = 275,
+    PERCENT_EXPECT = 276,
+    PERCENT_EXPECT_RR = 277,
+    PERCENT_FLAG = 278,
+    PERCENT_FILE_PREFIX = 279,
+    PERCENT_GLR_PARSER = 280,
+    PERCENT_INITIAL_ACTION = 281,
+    PERCENT_LANGUAGE = 282,
+    PERCENT_NAME_PREFIX = 283,
+    PERCENT_NO_DEFAULT_PREC = 284,
+    PERCENT_NO_LINES = 285,
+    PERCENT_NONDETERMINISTIC_PARSER = 286,
+    PERCENT_OUTPUT = 287,
+    PERCENT_REQUIRE = 288,
+    PERCENT_SKELETON = 289,
+    PERCENT_START = 290,
+    PERCENT_TOKEN_TABLE = 291,
+    PERCENT_VERBOSE = 292,
+    PERCENT_YACC = 293,
+    BRACED_CODE = 294,
+    BRACED_PREDICATE = 295,
+    BRACKETED_ID = 296,
+    CHAR = 297,
+    EPILOGUE = 298,
+    EQUAL = 299,
+    ID = 300,
+    ID_COLON = 301,
+    PERCENT_PERCENT = 302,
+    PIPE = 303,
+    PROLOGUE = 304,
+    SEMICOLON = 305,
+    TAG = 306,
+    TAG_ANY = 307,
+    TAG_NONE = 308,
+    INT = 309,
     PERCENT_PARAM = 310,
-    PERCENT_UNION = 311
+    PERCENT_UNION = 311,
+    PERCENT_EMPTY = 312
   };
 #endif
-/* Tokens.  */
-#define GRAM_EOF 0
-#define STRING 258
-#define INT 259
-#define PERCENT_TOKEN 260
-#define PERCENT_NTERM 261
-#define PERCENT_TYPE 262
-#define PERCENT_DESTRUCTOR 263
-#define PERCENT_PRINTER 264
-#define PERCENT_LEFT 265
-#define PERCENT_RIGHT 266
-#define PERCENT_NONASSOC 267
-#define PERCENT_PRECEDENCE 268
-#define PERCENT_PREC 269
-#define PERCENT_DPREC 270
-#define PERCENT_MERGE 271
-#define PERCENT_CODE 272
-#define PERCENT_DEFAULT_PREC 273
-#define PERCENT_DEFINE 274
-#define PERCENT_DEFINES 275
-#define PERCENT_ERROR_VERBOSE 276
-#define PERCENT_EXPECT 277
-#define PERCENT_EXPECT_RR 278
-#define PERCENT_FLAG 279
-#define PERCENT_FILE_PREFIX 280
-#define PERCENT_GLR_PARSER 281
-#define PERCENT_INITIAL_ACTION 282
-#define PERCENT_LANGUAGE 283
-#define PERCENT_NAME_PREFIX 284
-#define PERCENT_NO_DEFAULT_PREC 285
-#define PERCENT_NO_LINES 286
-#define PERCENT_NONDETERMINISTIC_PARSER 287
-#define PERCENT_OUTPUT 288
-#define PERCENT_REQUIRE 289
-#define PERCENT_SKELETON 290
-#define PERCENT_START 291
-#define PERCENT_TOKEN_TABLE 292
-#define PERCENT_VERBOSE 293
-#define PERCENT_YACC 294
-#define BRACED_CODE 295
-#define BRACED_PREDICATE 296
-#define BRACKETED_ID 297
-#define CHAR 298
-#define EPILOGUE 299
-#define EQUAL 300
-#define ID 301
-#define ID_COLON 302
-#define PERCENT_PERCENT 303
-#define PIPE 304
-#define PROLOGUE 305
-#define SEMICOLON 306
-#define TAG 307
-#define TAG_ANY 308
-#define TAG_NONE 309
-#define PERCENT_PARAM 310
-#define PERCENT_UNION 311
 
 /* Value type.  */
 #if ! defined GRAM_STYPE && ! defined GRAM_STYPE_IS_DECLARED
 typedef union GRAM_STYPE GRAM_STYPE;
 union GRAM_STYPE
 {
-#line 109 "src/parse-gram.y" /* yacc.c:1932  */
-
-  assoc assoc;
-  char *code;
-  char const *chars;
-  int integer;
-  named_ref *named_ref;
-  symbol *symbol;
-  symbol_list *list;
-  uniqstr uniqstr;
-  unsigned char character;
-
-#line 247 "src/parse-gram.y" /* yacc.c:1932  */
-
-  param_type param;
-
-#line 423 "src/parse-gram.y" /* yacc.c:1932  */
+#line 182 "src/parse-gram.y" /* yacc.c:1909  */
+unsigned char character;
+#line 186 "src/parse-gram.y" /* yacc.c:1909  */
+char *code;
+#line 191 "src/parse-gram.y" /* yacc.c:1909  */
+uniqstr uniqstr;
+#line 199 "src/parse-gram.y" /* yacc.c:1909  */
+int integer;
+#line 203 "src/parse-gram.y" /* yacc.c:1909  */
+symbol *symbol;
+#line 208 "src/parse-gram.y" /* yacc.c:1909  */
+assoc assoc;
+#line 211 "src/parse-gram.y" /* yacc.c:1909  */
+symbol_list *list;
+#line 214 "src/parse-gram.y" /* yacc.c:1909  */
+named_ref *named_ref;
+#line 241 "src/parse-gram.y" /* yacc.c:1909  */
+param_type param;
+#line 409 "src/parse-gram.y" /* yacc.c:1909  */
 code_props_type code_type;
+#line 647 "src/parse-gram.y" /* yacc.c:1909  */
 
-#line 211 "src/parse-gram.h" /* yacc.c:1932  */
+  struct
+  {
+    char const *chars;
+    muscle_kind kind;
+  } value;
+
+#line 167 "src/parse-gram.h" /* yacc.c:1909  */
 };
 # define GRAM_STYPE_IS_TRIVIAL 1
 # define GRAM_STYPE_IS_DECLARED 1

src/parse-gram.y

@@ -1,4 +1,4 @@
-%{/* Bison Grammar Parser                             -*- C -*-
+/* Bison Grammar Parser                             -*- C -*-
 
    Copyright (C) 2002-2013 Free Software Foundation, Inc.
 
@@ -17,45 +17,35 @@
    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
+%code requires
+{
+  #include "symlist.h"
+  #include "symtab.h"
+}
+
+%code top
+{
+  /* On column 0 to please syntax-check.  */
 #include <config.h>
-#include "system.h"
-
-#include "c-ctype.h"
-#include "complain.h"
-#include "conflicts.h"
-#include "files.h"
-#include "getargs.h"
-#include "gram.h"
-#include "muscle-tab.h"
-#include "named-ref.h"
-#include "quotearg.h"
-#include "reader.h"
-#include "symlist.h"
-#include "symtab.h"
-#include "scan-gram.h"
-#include "scan-code.h"
-#include "xmemdup0.h"
-
-#define YYLLOC_DEFAULT(Current, Rhs, N)  (Current) = lloc_default (Rhs, N)
-static YYLTYPE lloc_default (YYLTYPE const *, int);
-
-#define YY_LOCATION_PRINT(File, Loc) \
-          location_print (File, Loc)
-
-static void version_check (location const *loc, char const *version);
-
-/* Request detailed syntax error messages, and pass them to GRAM_ERROR.
-   FIXME: depends on the undocumented availability of YYLLOC.  */
-#undef  yyerror
-#define yyerror(Msg) \
-        gram_error (&yylloc, Msg)
-static void gram_error (location const *, char const *);
-
-static char const *char_name (char);
-%}
+}
 
 %code
 {
+  #include "system.h"
+
+  #include "c-ctype.h"
+  #include "complain.h"
+  #include "conflicts.h"
+  #include "files.h"
+  #include "getargs.h"
+  #include "gram.h"
+  #include "named-ref.h"
+  #include "quotearg.h"
+  #include "reader.h"
+  #include "scan-gram.h"
+  #include "scan-code.h"
+  #include "xmemdup0.h"
+
   static int current_prec = 0;
   static location current_lhs_location;
   static named_ref *current_lhs_named_ref;
@@ -66,20 +56,37 @@ static char const *char_name (char);
   /** Set the new current left-hand side symbol, possibly common
    * to several right-hand side parts of rule.
    */
-  static
-  void
-  current_lhs(symbol *sym, location loc, named_ref *ref)
-  {
-    current_lhs_symbol = sym;
-    current_lhs_location = loc;
-    /* In order to simplify memory management, named references for lhs
-       are always assigned by deep copy into the current symbol_list
-       node.  This is because a single named-ref in the grammar may
-       result in several uses when the user factors lhs between several
-       rules using "|".  Therefore free the parser's original copy.  */
-    free (current_lhs_named_ref);
-    current_lhs_named_ref = ref;
-  }
+  static void current_lhs (symbol *sym, location loc, named_ref *ref);
+
+  #define YYLLOC_DEFAULT(Current, Rhs, N)         \
+    (Current) = lloc_default (Rhs, N)
+  static YYLTYPE lloc_default (YYLTYPE const *, int);
+
+  #define YY_LOCATION_PRINT(File, Loc)            \
+    location_print (Loc, File)
+
+  /* Strip initial '{' and final '}' (must be first and last characters).
+     Return the result.  */
+  static char *strip_braces (char *code);
+
+  /* Convert CODE by calling code_props_plain_init if PLAIN, otherwise
+     code_props_symbol_action_init.  Call
+     gram_scanner_last_string_free to release the latest string from
+     the scanner (should be CODE). */
+  static char const *translate_code (char *code, location loc, bool plain);
+
+  /* Convert CODE by calling code_props_plain_init after having
+     stripped the first and last characters (expected to be '{', and
+     '}').  Call gram_scanner_last_string_free to release the latest
+     string from the scanner (should be CODE). */
+  static char const *translate_code_braceless (char *code, location loc);
+
+  static void version_check (location const *loc, char const *version);
+
+  static void gram_error (location const *, char const *);
+
+  /* A string that describes a char (e.g., 'a' -> "'a'").  */
+  static char const *char_name (char);
 
   #define YYTYPE_INT16 int_fast16_t
   #define YYTYPE_INT8 int_fast8_t
@@ -87,8 +94,8 @@ static char const *char_name (char);
   #define YYTYPE_UINT8 uint_fast8_t
 }
 
-%define api.prefix "gram_"
-%define api.pure
+%define api.prefix {gram_}
+%define api.pure full
 %define locations
 %define parse.error verbose
 %define parse.lac full
@@ -105,23 +112,9 @@ static char const *char_name (char);
   boundary_set (&@$.end, current_file, 1, 1);
 }
 
-%union
-{
-  assoc assoc;
-  char *code;
-  char const *chars;
-  int integer;
-  named_ref *named_ref;
-  symbol *symbol;
-  symbol_list *list;
-  uniqstr uniqstr;
-  unsigned char character;
-};
-
 /* Define the tokens together with their human representation.  */
 %token GRAM_EOF 0 "end of file"
 %token STRING     "string"
-%token INT        "integer"
 
 %token PERCENT_TOKEN       "%token"
 %token PERCENT_NTERM       "%nterm"
@@ -186,18 +179,16 @@ static char const *char_name (char);
 %token TAG_ANY         "<*>"
 %token TAG_NONE        "<>"
 
+%union {unsigned char character;}
 %type <character> CHAR
 %printer { fputs (char_name ($$), yyo); } CHAR
 
-/* braceless is not to be used for rule or symbol actions, as it
-   calls code_props_plain_init.  */
-%type <chars> STRING "%{...%}" EPILOGUE braceless content.opt
-%type <code> "{...}" "%?{...}"
-%printer { fputs (quotearg_style (c_quoting_style, $$), yyo); }
-         STRING
-%printer { fprintf (yyo, "{\n%s\n}", $$); }
-         braceless content.opt "{...}" "%{...%}" EPILOGUE
+%union {char *code;};
+%type <code> "{...}" "%?{...}" "%{...%}" EPILOGUE STRING
+%printer { fputs (quotearg_style (c_quoting_style, $$), yyo); } STRING
+%printer { fprintf (yyo, "{\n%s\n}", $$); } <code>
 
+%union {uniqstr uniqstr;}
 %type <uniqstr> BRACKETED_ID ID ID_COLON PERCENT_FLAG TAG tag variable
 %printer { fputs ($$, yyo); } <uniqstr>
 %printer { fprintf (yyo, "[%s]", $$); } BRACKETED_ID
@@ -205,15 +196,22 @@ static char const *char_name (char);
 %printer { fprintf (yyo, "%%%s", $$); } PERCENT_FLAG
 %printer { fprintf (yyo, "<%s>", $$); } TAG tag
 
-%type <integer> INT
+%union {int integer;};
+%token <integer> INT "integer"
 %printer { fprintf (yyo, "%d", $$); } <integer>
 
+%union {symbol *symbol;}
 %type <symbol> id id_colon string_as_id symbol symbol.prec
 %printer { fprintf (yyo, "%s", $$->tag); } <symbol>
 %printer { fprintf (yyo, "%s:", $$->tag); } id_colon
 
+%union {assoc assoc;};
 %type <assoc> precedence_declarator
+
+%union {symbol_list *list;}
 %type <list>  symbols.1 symbols.prec generic_symlist generic_symlist_item
+
+%union {named_ref *named_ref;}
 %type <named_ref> named_ref.opt
 
 /*---------.
@@ -221,8 +219,6 @@ static char const *char_name (char);
 `---------*/
 %code requires
 {
-# ifndef PARAM_TYPE
-#  define PARAM_TYPE
   typedef enum
   {
     param_none   = 0,
@@ -230,7 +226,6 @@ static char const *char_name (char);
     param_parse  = 1 << 1,
     param_both   = param_lex | param_parse
   } param_type;
-# endif
 };
 %code
 {
@@ -243,20 +238,17 @@ static char const *char_name (char);
   static void add_param (param_type type, char *decl, location loc);
   static param_type current_param = param_none;
 };
-%union
-{
-  param_type param;
-}
+%union {param_type param;}
 %token <param> PERCENT_PARAM "%param";
 %printer
 {
   switch ($$)
     {
 #define CASE(In, Out)                                           \
-      case param_ ## In: fputs ("%" #Out, stderr); break
-      CASE(lex,   lex-param);
-      CASE(parse, parse-param);
-      CASE(both,  param);
+      case param_ ## In: fputs ("%" #Out, yyo); break
+      CASE (lex,   lex-param);
+      CASE (parse, parse-param);
+      CASE (both,  param);
 #undef CASE
       case param_none: aver (false); break;
     }
@@ -278,7 +270,7 @@ input:
         `------------------------------------*/
 
 prologue_declarations:
-  /* Nothing */
+  %empty
 | prologue_declarations prologue_declaration
 ;
 
@@ -286,21 +278,17 @@ prologue_declaration:
   grammar_declaration
 | "%{...%}"
     {
-      code_props plain_code;
-      code_props_plain_init (&plain_code, $1, @1);
-      code_props_translate_code (&plain_code);
-      gram_scanner_last_string_free ();
       muscle_code_grow (union_seen ? "post_prologue" : "pre_prologue",
-                        plain_code.code, @1);
+                        translate_code ($1, @1, true), @1);
       code_scanner_last_string_free ();
     }
 | "%<flag>"
     {
       muscle_percent_define_ensure ($1, @1, true);
     }
-| "%define" variable content.opt
+| "%define" variable value
     {
-      muscle_percent_define_insert ($2, @2, $3,
+      muscle_percent_define_insert ($2, @2, $3.kind, $3.chars,
                                     MUSCLE_PERCENT_DEFINE_GRAMMAR_FILE);
     }
 | "%defines"                       { defines_flag = true; }
@@ -311,7 +299,8 @@ prologue_declaration:
     }
 | "%error-verbose"
     {
-      muscle_percent_define_insert ("parse.error", @1, "verbose",
+      muscle_percent_define_insert ("parse.error", @1, muscle_keyword,
+                                    "verbose",
                                     MUSCLE_PERCENT_DEFINE_GRAMMAR_FILE);
     }
 | "%expect" INT                    { expected_sr_conflicts = $2; }
@@ -324,11 +313,7 @@ prologue_declaration:
     }
 | "%initial-action" "{...}"
     {
-      code_props action;
-      code_props_symbol_action_init (&action, $2, @2);
-      code_props_translate_code (&action);
-      gram_scanner_last_string_free ();
-      muscle_code_grow ("initial_action", action.code, @2);
+      muscle_code_grow ("initial_action", translate_code ($2, @2, false), @2);
       code_scanner_last_string_free ();
     }
 | "%language" STRING            { language_argmatch ($2, grammar_prio, @1); }
@@ -405,16 +390,17 @@ grammar_declaration:
     {
       default_prec = false;
     }
-| "%code" braceless
+| "%code" "{...}"
     {
       /* Do not invoke muscle_percent_code_grow here since it invokes
          muscle_user_name_list_grow.  */
-      muscle_code_grow ("percent_code()", $2, @2);
+      muscle_code_grow ("percent_code()",
+                        translate_code_braceless ($2, @2), @2);
       code_scanner_last_string_free ();
     }
-| "%code" ID braceless
+| "%code" ID "{...}"
     {
-      muscle_percent_code_grow ($2, @2, $3, @3);
+      muscle_percent_code_grow ($2, @2, translate_code_braceless ($3, @3), @3);
       code_scanner_last_string_free ();
     }
 ;
@@ -434,15 +420,15 @@ code_props_type:
 %token PERCENT_UNION "%union";
 
 union_name:
-  /* Nothing. */ {}
-| ID             { muscle_code_grow ("union_name", $1, @1); }
+  %empty {}
+| ID     { muscle_code_grow ("union_name", $1, @1); }
 ;
 
 grammar_declaration:
-  "%union" union_name braceless
+  "%union" union_name "{...}"
     {
       union_seen = true;
-      muscle_code_grow ("stype", $3, @3);
+      muscle_code_grow ("union_members", translate_code_braceless ($3, @3), @3);
       code_scanner_last_string_free ();
     }
 ;
@@ -494,8 +480,8 @@ precedence_declarator:
 ;
 
 tag.opt:
-  /* Nothing. */ { current_type = NULL; }
-| TAG            { current_type = $1; tag_seen = true; }
+  %empty { current_type = NULL; }
+| TAG    { current_type = $1; tag_seen = true; }
 ;
 
 /* Just like symbols.1 but accept INT for the sake of POSIX.  */
@@ -507,8 +493,17 @@ symbols.prec:
 ;
 
 symbol.prec:
-  symbol     { $$ = $1; }
-| symbol INT { $$ = $1; symbol_user_token_number_set ($1, $2, @2); }
+  symbol
+    {
+      $$ = $1;
+      symbol_class_set ($1, token_sym, @1, false);
+    }
+| symbol INT
+    {
+      $$ = $1;
+      symbol_user_token_number_set ($1, $2, @2);
+      symbol_class_set ($1, token_sym, @1, false);
+    }
 ;
 
 /* One or more symbols to be %typed. */
@@ -609,8 +604,9 @@ rhses.1:
 | rhses.1 ";"
 ;
 
+%token PERCENT_EMPTY "%empty";
 rhs:
-  /* Nothing.  */
+  %empty
     { grammar_current_rule_begin (current_lhs_symbol, current_lhs_location,
                                   current_lhs_named_ref); }
 | rhs symbol named_ref.opt
@@ -619,6 +615,8 @@ rhs:
     { grammar_current_rule_action_append ($2, @2, $3, false); }
 | rhs "%?{...}"
     { grammar_current_rule_action_append ($2, @2, NULL, true); }
+| rhs "%empty"
+    { grammar_current_rule_empty_set (@2); }
 | rhs "%prec" symbol
     { grammar_current_rule_prec_set ($3, @3); }
 | rhs "%dprec" INT
@@ -628,44 +626,47 @@ rhs:
 ;
 
 named_ref.opt:
-  /* Nothing. */ { $$ = 0; }
-|
-  BRACKETED_ID   { $$ = named_ref_new($1, @1); }
+  %empty         { $$ = 0; }
+| BRACKETED_ID   { $$ = named_ref_new ($1, @1); }
 ;
 
-/*---------------------------.
-| variable and content.opt.  |
-`---------------------------*/
+/*---------------------.
+| variable and value.  |
+`---------------------*/
 
 /* The STRING form of variable is deprecated and is not M4-friendly.
-   For example, M4 fails for `%define "[" "value"'.  */
+   For example, M4 fails for '%define "[" "value"'.  */
 variable:
   ID
 | STRING { $$ = uniqstr_new ($1); }
 ;
 
 /* Some content or empty by default. */
-content.opt:
-  /* Nothing. */   { $$ = ""; }
-| ID { $$ = $1; }
-| STRING
-;
-
-
-/*------------.
-| braceless.  |
-`------------*/
-
-braceless:
-  "{...}"
+%code requires {#include "muscle-tab.h"};
+%union
+{
+  struct
+  {
+    char const *chars;
+    muscle_kind kind;
+  } value;
+};
+%type <value> value;
+%printer
+{
+  switch ($$.kind)
     {
-      code_props plain_code;
-      $1[strlen ($1) - 1] = '\n';
-      code_props_plain_init (&plain_code, $1+1, @1);
-      code_props_translate_code (&plain_code);
-      gram_scanner_last_string_free ();
-      $$ = plain_code.code;
+    case muscle_code:    fprintf (yyo,  "{%s}",  $$.chars); break;
+    case muscle_keyword: fprintf (yyo,   "%s",   $$.chars); break;
+    case muscle_string:  fprintf (yyo, "\"%s\"", $$.chars); break;
     }
+} <value>;
+
+value:
+  %empty  { $$.kind = muscle_keyword; $$.chars = ""; }
+| ID      { $$.kind = muscle_keyword; $$.chars = $1; }
+| STRING  { $$.kind = muscle_string;  $$.chars = $1; }
+| "{...}" { $$.kind = muscle_code;    $$.chars = strip_braces ($1); }
 ;
 
 
@@ -707,14 +708,10 @@ string_as_id:
 ;
 
 epilogue.opt:
-  /* Nothing.  */
+  %empty
 | "%%" EPILOGUE
     {
-      code_props plain_code;
-      code_props_plain_init (&plain_code, $2, @2);
-      code_props_translate_code (&plain_code);
-      gram_scanner_last_string_free ();
-      muscle_code_grow ("epilogue", plain_code.code, @2);
+      muscle_code_grow ("epilogue", translate_code ($2, @2, true), @2);
       code_scanner_last_string_free ();
     }
 ;
@@ -750,6 +747,33 @@ lloc_default (YYLTYPE const *rhs, int n)
   return loc;
 }
 
+static
+char *strip_braces (char *code)
+{
+  code[strlen (code) - 1] = 0;
+  return code + 1;
+}
+
+static
+char const *
+translate_code (char *code, location loc, bool plain)
+{
+  code_props plain_code;
+  if (plain)
+    code_props_plain_init (&plain_code, code, loc);
+  else
+    code_props_symbol_action_init (&plain_code, code, loc);
+  code_props_translate_code (&plain_code);
+  gram_scanner_last_string_free ();
+  return plain_code.code;
+}
+
+static
+char const *
+translate_code_braceless (char *code, location loc)
+{
+  return translate_code (strip_braces (code), loc, true);
+}
 
 static void
 add_param (param_type type, char *decl, location loc)
@@ -832,3 +856,18 @@ char_name (char c)
       return quotearg_style (escape_quoting_style, buf);
     }
 }
+
+static
+void
+current_lhs (symbol *sym, location loc, named_ref *ref)
+{
+  current_lhs_symbol = sym;
+  current_lhs_location = loc;
+  /* In order to simplify memory management, named references for lhs
+     are always assigned by deep copy into the current symbol_list
+     node.  This is because a single named-ref in the grammar may
+     result in several uses when the user factors lhs between several
+     rules using "|".  Therefore free the parser's original copy.  */
+  free (current_lhs_named_ref);
+  current_lhs_named_ref = ref;
+}

src/print-xml.c

@@ -45,7 +45,8 @@ struct escape_buf
   char *ptr;
   size_t size;
 };
-static struct escape_buf escape_bufs[3];
+enum { num_escape_bufs = 3 };
+static struct escape_buf escape_bufs[num_escape_bufs];
 
 
 /*--------------------------------.
@@ -64,40 +65,39 @@ print_core (FILE *out, int level, state *s)
   sitems = itemset;
   snritems = nitemset;
 
-  if (!snritems) {
-    xml_puts (out, level, "<itemset/>");
-    return;
-  }
+  if (!snritems)
+    {
+      xml_puts (out, level, "<itemset/>");
+      return;
+    }
 
   xml_puts (out, level, "<itemset>");
 
   for (i = 0; i < snritems; i++)
     {
       bool printed = false;
-      item_number *sp;
-      item_number *sp1;
-      rule_number r;
+      item_number *sp1 = ritem + sitems[i];
+      item_number *sp = sp1;
+      rule *r;
 
-      sp1 = sp = ritem + sitems[i];
-
-      while (*sp >= 0)
+      while (0 <= *sp)
         sp++;
 
-      r = item_number_as_rule_number (*sp);
-      sp = rules[r].rhs;
+      r = &rules[item_number_as_rule_number (*sp)];
+      sp = r->rhs;
 
       /* Display the lookahead tokens?  */
       if (item_number_is_rule_number (*sp1))
         {
           reductions *reds = s->reductions;
-          int red = state_reduction_find (s, &rules[r]);
+          int red = state_reduction_find (s, r);
           /* Print item with lookaheads if there are. */
           if (reds->lookahead_tokens && red != -1)
             {
               xml_printf (out, level + 1,
                           "<item rule-number=\"%d\" point=\"%d\">",
-                          rules[r].number, sp1 - sp);
-              state_rule_lookahead_tokens_print_xml (s, &rules[r],
+                          r->number, sp1 - sp);
+              state_rule_lookahead_tokens_print_xml (s, r,
                                                      out, level + 2);
               xml_puts (out, level + 1, "</item>");
               printed = true;
@@ -105,12 +105,10 @@ print_core (FILE *out, int level, state *s)
         }
 
       if (!printed)
-        {
-          xml_printf (out, level + 1,
-                      "<item rule-number=\"%d\" point=\"%d\"/>",
-                      rules[r].number,
-                      sp1 - sp);
-        }
+        xml_printf (out, level + 1,
+                    "<item rule-number=\"%d\" point=\"%d\"/>",
+                    r->number,
+                    sp1 - sp);
     }
   xml_puts (out, level, "</itemset>");
 }
@@ -135,10 +133,11 @@ print_transitions (state *s, FILE *out, int level)
       }
 
   /* Nothing to report. */
-  if (!n) {
-    xml_puts (out, level, "<transitions/>");
-    return;
-  }
+  if (!n)
+    {
+      xml_puts (out, level, "<transitions/>");
+      return;
+    }
 
   /* Report lookahead tokens and shifts.  */
   xml_puts (out, level, "<transitions>");
@@ -189,10 +188,11 @@ print_errs (FILE *out, int level, state *s)
       count = true;
 
   /* Nothing to report. */
-  if (!count) {
-    xml_puts (out, level, "<errors/>");
-    return;
-  }
+  if (!count)
+    {
+      xml_puts (out, level, "<errors/>");
+      return;
+    }
 
   /* Report lookahead tokens and errors.  */
   xml_puts (out, level, "<errors>");
@@ -209,7 +209,7 @@ print_errs (FILE *out, int level, state *s)
 
 
 /*-------------------------------------------------------------------------.
-| Report a reduction of RULE on LOOKAHEAD_TOKEN (which can be `default').  |
+| Report a reduction of RULE on LOOKAHEAD_TOKEN (which can be 'default').  |
 | If not ENABLED, the rule is masked by a shift or a reduce (S/R and       |
 | R/R conflicts).                                                          |
 `-------------------------------------------------------------------------*/
@@ -286,10 +286,11 @@ print_reductions (FILE *out, int level, state *s)
       }
 
   /* Nothing to report. */
-  if (!report) {
-    xml_puts (out, level, "<reductions/>");
-    return;
-  }
+  if (!report)
+    {
+      xml_puts (out, level, "<reductions/>");
+      return;
+    }
 
   xml_puts (out, level, "<reductions>");
 
@@ -496,7 +497,6 @@ xml_escape (char const *str)
 void
 print_xml (void)
 {
-  state_number i;
   int level = 0;
 
   FILE *out = xfopen (spec_xml_file, "w");
@@ -522,8 +522,11 @@ print_xml (void)
   /* print automaton */
   fputc ('\n', out);
   xml_puts (out, level + 1, "<automaton>");
-  for (i = 0; i < nstates; i++)
-    print_state (out, level + 2, states[i]);
+  {
+    state_number i;
+    for (i = 0; i < nstates; i++)
+      print_state (out, level + 2, states[i]);
+  }
   xml_puts (out, level + 1, "</automaton>");
 
   bitset_free (no_reduce_set);
@@ -531,8 +534,11 @@ print_xml (void)
 
   xml_puts (out, 0, "</bison-xml-report>");
 
-  free (escape_bufs[0].ptr);
-  free (escape_bufs[1].ptr);
+  {
+    int i;
+    for (i = 0; i < num_escape_bufs; ++i)
+      free (escape_bufs[i].ptr);
+  }
 
   xfclose (out);
 }

src/print.c

@@ -106,8 +106,11 @@ print_core (FILE *out, state *s)
       for (sp = rules[r].rhs; sp < sp1; sp++)
         fprintf (out, " %s", symbols[*sp]->tag);
       fputs (" .", out);
-      for (/* Nothing */; *sp >= 0; ++sp)
-        fprintf (out, " %s", symbols[*sp]->tag);
+      if (0 <= *rules[r].rhs)
+        for (/* Nothing */; 0 <= *sp; ++sp)
+          fprintf (out, " %s", symbols[*sp]->tag);
+      else
+        fprintf (out, " %%empty");
 
       /* Display the lookahead tokens?  */
       if (report_flag & report_lookahead_tokens
@@ -206,7 +209,7 @@ print_errs (FILE *out, state *s)
 
 
 /*-------------------------------------------------------------------------.
-| Report a reduction of RULE on LOOKAHEAD_TOKEN (which can be `default').  |
+| Report a reduction of RULE on LOOKAHEAD_TOKEN (which can be 'default').  |
 | If not ENABLED, the rule is masked by a shift or a reduce (S/R and       |
 | R/R conflicts).                                                          |
 `-------------------------------------------------------------------------*/
@@ -514,7 +517,7 @@ print_results (void)
   print_grammar (out);
 
   /* If the whole state item sets, not only the kernels, are wanted,
-     `closure' will be run, which needs memory allocation/deallocation.   */
+     'closure' will be run, which needs memory allocation/deallocation.   */
   if (report_flag & report_itemsets)
     new_closure (nritems);
   /* Storage for print_reductions.  */

src/print_graph.c

@@ -84,8 +84,11 @@ print_core (struct obstack *oout, state *s)
 
       obstack_1grow (oout, '.');
 
-      for (/* Nothing */; *sp >= 0; ++sp)
-        obstack_printf (oout, " %s", escape (symbols[*sp]->tag));
+      if (0 <= *r->rhs)
+        for (/* Nothing */; *sp >= 0; ++sp)
+          obstack_printf (oout, " %s", escape (symbols[*sp]->tag));
+      else
+        obstack_printf (oout, " %%empty");
 
       /* Experimental feature: display the lookahead tokens. */
       if (report_flag & report_lookahead_tokens

src/reader.c

@@ -267,9 +267,9 @@ symbol_should_be_used (symbol_list const *s, bool *midrule_warning)
     return true;
   if ((s->midrule && s->midrule->action_props.is_value_used)
       || (s->midrule_parent_rule
-          && symbol_list_n_get (s->midrule_parent_rule,
-                                s->midrule_parent_rhs_index)
-               ->action_props.is_value_used))
+          && (symbol_list_n_get (s->midrule_parent_rule,
+                                 s->midrule_parent_rhs_index)
+              ->action_props.is_value_used)))
     {
       *midrule_warning = true;
       return true;
@@ -321,7 +321,7 @@ grammar_rule_check (const symbol_list *r)
         bool midrule_warning = false;
         if (!l->action_props.is_value_used
             && symbol_should_be_used (l, &midrule_warning)
-            /* The default action, $$ = $1, `uses' both.  */
+            /* The default action, $$ = $1, 'uses' both.  */
             && (r->action_props.code || (n != 0 && n != 1)))
           {
             warnings warn_flag = midrule_warning ? Wmidrule_values : Wother;
@@ -333,6 +333,18 @@ grammar_rule_check (const symbol_list *r)
       }
   }
 
+  /* Check that %empty => empty rule.  */
+  if (r->percent_empty_loc.start.file
+      && r->next && r->next->content.sym)
+    complain (&r->percent_empty_loc, complaint,
+              _("%%empty on non-empty rule"));
+
+  /* Check that empty rule => %empty.  */
+  if (!(r->next && r->next->content.sym)
+      && !r->midrule_parent_rule
+      && !r->percent_empty_loc.start.file)
+    complain (&r->location, Wempty_rule, _("empty rule without %%empty"));
+
   /* See comments in grammar_current_rule_prec_set for how POSIX
      mandates this complaint.  It's only for identifiers, so skip
      it for char literals and strings, which are always tokens.  */
@@ -430,8 +442,26 @@ grammar_current_rule_prec_set (symbol *precsym, location loc)
      token.  */
   symbol_class_set (precsym, token_sym, loc, false);
   if (current_rule->ruleprec)
-    complain (&loc, complaint, _("only one %s allowed per rule"), "%prec");
-  current_rule->ruleprec = precsym;
+    duplicate_directive ("%prec",
+                         current_rule->ruleprec->location, loc);
+  else
+    current_rule->ruleprec = precsym;
+}
+
+/* Set %empty for the current rule. */
+
+void
+grammar_current_rule_empty_set (location loc)
+{
+  /* If %empty is used and -Wno-empty-rule is not, then enable
+     -Wempty-rule.  */
+  if (warning_is_unset (Wempty_rule))
+    warning_argmatch ("empty-rule", 0, 0);
+  if (current_rule->percent_empty_loc.start.file)
+    duplicate_directive ("%empty",
+                         current_rule->percent_empty_loc, loc);
+  else
+    current_rule->percent_empty_loc = loc;
 }
 
 /* Attach dynamic precedence DPREC to the current rule. */
@@ -446,8 +476,13 @@ grammar_current_rule_dprec_set (int dprec, location loc)
     complain (&loc, complaint, _("%s must be followed by positive number"),
               "%dprec");
   else if (current_rule->dprec != 0)
-    complain (&loc, complaint, _("only one %s allowed per rule"), "%dprec");
-  current_rule->dprec = dprec;
+    duplicate_directive ("%dprec",
+                         current_rule->dprec_location, loc);
+  else
+    {
+      current_rule->dprec = dprec;
+      current_rule->dprec_location = loc;
+    }
 }
 
 /* Attach a merge function NAME with argument type TYPE to current
@@ -460,9 +495,13 @@ grammar_current_rule_merge_set (uniqstr name, location loc)
     complain (&loc, Wother, _("%s affects only GLR parsers"),
               "%merge");
   if (current_rule->merger != 0)
-    complain (&loc, complaint, _("only one %s allowed per rule"), "%merge");
-  current_rule->merger = get_merge_function (name);
-  current_rule->merger_declaration_location = loc;
+    duplicate_directive ("%merge",
+                         current_rule->merger_declaration_location, loc);
+  else
+    {
+      current_rule->merger = get_merge_function (name);
+      current_rule->merger_declaration_location = loc;
+    }
 }
 
 /* Attach SYM to the current rule.  If needed, move the previous
@@ -477,7 +516,7 @@ grammar_current_rule_symbol_append (symbol *sym, location loc,
     grammar_midrule_action ();
   p = grammar_symbol_append (sym, loc);
   if (name)
-    assign_named_ref(p, name);
+    assign_named_ref (p, name);
   if (sym->status == undeclared || sym->status == used)
     sym->status = needed;
 }
@@ -507,7 +546,7 @@ packgram (void)
 {
   unsigned int itemno = 0;
   rule_number ruleno = 0;
-  symbol_list *p = grammar;
+  symbol_list *p;
 
   ritem = xnmalloc (nritems + 1, sizeof *ritem);
 
@@ -516,9 +555,8 @@ packgram (void)
 
   rules = xnmalloc (nrules, sizeof *rules);
 
-  while (p)
+  for (p = grammar; p; p = p->next)
     {
-      int rule_length = 0;
       symbol *ruleprec = p->ruleprec;
       record_merge_function_type (p->merger, p->content.sym->type_name,
                                   p->merger_declaration_location);
@@ -536,14 +574,14 @@ packgram (void)
       rules[ruleno].action_location = p->action_props.location;
       rules[ruleno].is_predicate = p->action_props.is_predicate;
 
-      /* If the midrule's $$ is set or its $n is used, remove the `$' from the
+      /* If the midrule's $$ is set or its $n is used, remove the '$' from the
          symbol name so that it's a user-defined symbol so that the default
          %destructor and %printer apply.  */
       if (p->midrule_parent_rule
           && (p->action_props.is_value_used
-              || symbol_list_n_get (p->midrule_parent_rule,
-                                    p->midrule_parent_rhs_index)
-                   ->action_props.is_value_used))
+              || (symbol_list_n_get (p->midrule_parent_rule,
+                                     p->midrule_parent_rhs_index)
+                  ->action_props.is_value_used)))
         p->content.sym->tag += 1;
 
       /* Don't check the generated rule 0.  It has no action, so some rhs
@@ -552,24 +590,27 @@ packgram (void)
       if (p != grammar)
         grammar_rule_check (p);
 
-      for (p = p->next; p && p->content.sym; p = p->next)
-        {
-          ++rule_length;
+      {
+        size_t rule_length = 0;
+        for (p = p->next; p->content.sym; p = p->next)
+          {
+            ++rule_length;
 
-          /* Don't allow rule_length == INT_MAX, since that might
-             cause confusion with strtol if INT_MAX == LONG_MAX.  */
-          if (rule_length == INT_MAX)
-            complain (&rules[ruleno].location, fatal, _("rule is too long"));
+            /* Don't allow rule_length == INT_MAX, since that might
+               cause confusion with strtol if INT_MAX == LONG_MAX.  */
+            if (rule_length == INT_MAX)
+              complain (&rules[ruleno].location, fatal, _("rule is too long"));
 
-          /* item_number = symbol_number.
-             But the former needs to contain more: negative rule numbers. */
-          ritem[itemno++] =
-            symbol_number_as_item_number (p->content.sym->number);
-          /* A rule gets by default the precedence and associativity
-             of its last token.  */
-          if (p->content.sym->class == token_sym && default_prec)
-            rules[ruleno].prec = p->content.sym;
-        }
+            /* item_number = symbol_number.
+               But the former needs to contain more: negative rule numbers. */
+            ritem[itemno++] =
+              symbol_number_as_item_number (p->content.sym->number);
+            /* A rule gets by default the precedence and associativity
+               of its last token.  */
+            if (p->content.sym->class == token_sym && default_prec)
+              rules[ruleno].prec = p->content.sym;
+          }
+      }
 
       /* If this rule has a %prec,
          the specified symbol's precedence replaces the default.  */
@@ -583,9 +624,6 @@ packgram (void)
       aver (itemno < ITEM_NUMBER_MAX);
       ++ruleno;
       aver (ruleno < RULE_NUMBER_MAX);
-
-      if (p)
-        p = p->next;
     }
 
   aver (itemno == nritems);
@@ -713,7 +751,7 @@ check_and_convert_grammar (void)
   /* Insert the initial rule, whose line is that of the first rule
      (not that of the start symbol):
 
-     accept: %start EOF.  */
+     $accept: %start $end.  */
   {
     symbol_list *p = symbol_list_sym_new (accept, empty_location);
     p->location = grammar->location;
@@ -726,7 +764,8 @@ check_and_convert_grammar (void)
     grammar = p;
   }
 
-  aver (nsyms <= SYMBOL_NUMBER_MAXIMUM && nsyms == ntokens + nvars);
+  aver (nsyms <= SYMBOL_NUMBER_MAXIMUM);
+  aver (nsyms == ntokens + nvars);
 
   /* Assign the symbols their symbol numbers.  Write #defines for the
      token symbols into FDEFINES if requested.  */
@@ -737,11 +776,11 @@ check_and_convert_grammar (void)
      action type checking.
 
      Before invoking grammar_rule_check (in packgram below) on any rule, make
-     sure all actions have already been scanned in order to set `used' flags.
+     sure all actions have already been scanned in order to set 'used' flags.
      Otherwise, checking that a midrule's $$ should be set will not always work
      properly because the check must forward-reference the midrule's parent
-     rule.  For the same reason, all the `used' flags must be set before
-     checking whether to remove `$' from any midrule symbol name (also in
+     rule.  For the same reason, all the 'used' flags must be set before
+     checking whether to remove '$' from any midrule symbol name (also in
      packgram).  */
   {
     symbol_list *sym;

src/reader.h

@@ -47,6 +47,8 @@ void grammar_current_rule_begin (symbol *lhs, location loc,
                                  named_ref *lhs_named_ref);
 void grammar_current_rule_end (location loc);
 void grammar_midrule_action (void);
+/* Apply %empty to the current rule.  */
+void grammar_current_rule_empty_set (location loc);
 void grammar_current_rule_prec_set (symbol *precsym, location loc);
 void grammar_current_rule_dprec_set (int dprec, location loc);
 void grammar_current_rule_merge_set (uniqstr name, location loc);

src/reduce.c

@@ -49,7 +49,7 @@ static bitset P;
 static bitset V;
 
 /* Set of symbols used to define rule precedence (so they are
-   `useless', but no warning should be issued).  */
+   'useless', but no warning should be issued).  */
 static bitset V1;
 
 static rule_number nuseful_productions;

src/scan-code.l

@@ -78,8 +78,9 @@ static bool untyped_var_seen;
 
 /* POSIX says that a tag must be both an id and a C union member, but
    historically almost any character is allowed in a tag.  We disallow
-   NUL and newline, as this simplifies our implementation.  */
-tag      [^\0\n>]+
+   NUL and newline, as this simplifies our implementation.  We allow
+   "->" as a means to dereference a pointer.  */
+tag      ([^\0\n>]|->)+
 
 /* Zero or more instances of backslash-newline.  Following GCC, allow
    white space between the backslash and the newline.  */
@@ -95,26 +96,6 @@ ref      -?[0-9]+|{id}|"["{id}"]"|"$"
 %%
 
 %{
-  /* Nesting level of the current code in braces.  */
-  int braces_level = 0;
-
-  /* Whether a semicolon is probably needed.
-
-     The heuristic is that a semicolon is not needed after '{', '}',
-     ';', or a C preprocessor directive, and that whitespaces and
-     comments do not affect this flag.  Note that '{' does not need a
-     semicolon because of '{}'.  A semicolon may be needed before a
-     cpp directive, but don't bother.
-
-     While it is maintained in several start-conditions (factoring
-     opportunities), it is meaningful only for SC_RULE_ACTION. */
-  bool need_semicolon = false;
-
-  /* Whether in a C preprocessor directive.  Don't use a start condition
-     for this because, at the end of strings and comments, we still need
-     to know whether we're in a directive.  */
-  bool in_cpp = false;
-
   /* This scanner is special: it is invoked only once, henceforth
      is expected to return only once.  This initialization is
      therefore done once per action to translate. */
@@ -167,32 +148,14 @@ ref      -?[0-9]+|{id}|"["{id}"]"|"$"
 
 <SC_RULE_ACTION,SC_SYMBOL_ACTION>
 {
-  "'" {
-    STRING_GROW;
-    BEGIN SC_CHARACTER;
-    need_semicolon = true;
-  }
-  "\"" {
-    STRING_GROW;
-    BEGIN SC_STRING;
-    need_semicolon = true;
-  }
-  "/"{splice}"*" {
-    STRING_GROW;
-    BEGIN SC_COMMENT;
-  }
-  "/"{splice}"/" {
-    STRING_GROW;
-    BEGIN SC_LINE_COMMENT;
-  }
+  "'"              STRING_GROW; BEGIN SC_CHARACTER;
+  "\""             STRING_GROW; BEGIN SC_STRING;
+  "/"{splice}"*"   STRING_GROW; BEGIN SC_COMMENT;
+  "/"{splice}"/"   STRING_GROW; BEGIN SC_LINE_COMMENT;
+
   [$@]  {
     complain (loc, Wother, _("stray '%s'"), yytext);
     obstack_escape (&obstack_for_string, yytext);
-    need_semicolon = true;
-  }
-  [\[\]]  {
-    obstack_escape (&obstack_for_string, yytext);
-    need_semicolon = true;
   }
 }
 
@@ -203,51 +166,13 @@ ref      -?[0-9]+|{id}|"["{id}"]"|"$"
     handle_action_dollar (self->rule, yytext, *loc);
     if (ref_tail_fields)
       obstack_sgrow (&obstack_for_string, ref_tail_fields);
-    need_semicolon = true;
   }
   "@"{ref} {
     ref_tail_fields = NULL;
     handle_action_at (self->rule, yytext, *loc);
     if (ref_tail_fields)
       obstack_sgrow (&obstack_for_string, ref_tail_fields);
-    need_semicolon = true;
   }
-
-  ";"  STRING_GROW;                 need_semicolon = false;
-  "{"  STRING_GROW; ++braces_level; need_semicolon = false;
-  "}"  {
-    bool outer_brace = --braces_level == 0;
-
-    /* As an undocumented Bison extension, append ';' before the last
-       brace in braced code, so that the user code can omit trailing
-       ';'.  But do not append ';' if emulating Yacc, since Yacc does
-       not append one.  This is deprecated since release 2.4.1.  */
-    if (outer_brace && !yacc_flag && language_prio == default_prio
-        && skeleton_prio == default_prio && need_semicolon && ! in_cpp)
-      {
-        unsigned int indent = 0;
-        complain_indent (loc, Wdeprecated, &indent,
-                         _("a ';' might be needed at the end of action code"));
-        indent += SUB_INDENT;
-        complain_indent (loc, Wdeprecated | silent | no_caret, &indent,
-                         _("future versions of Bison will not add the ';'"));
-        obstack_1grow (&obstack_for_string, ';');
-      }
-
-    STRING_GROW;
-    need_semicolon = false;
-  }
-
-  /* Preprocessing directives should only be recognized at the beginning
-     of lines, allowing whitespace including comments, but in C/C++,
-     '#' can only be the start of preprocessor directives or within
-     '#define' directives anyway, so don't bother with begin of line.  */
-  "#"       STRING_GROW; in_cpp = true;
-
-  {splice}  STRING_GROW;
-  [\n\r]    STRING_GROW; if (in_cpp) in_cpp = need_semicolon = false;
-  [ \t\f]   STRING_GROW;
-  .         STRING_GROW; need_semicolon = true;
 }
 
 <SC_SYMBOL_ACTION>
@@ -417,8 +342,19 @@ show_sub_message (warnings warning,
     {
       static struct obstack msg_buf;
       const char *tail = explicit_bracketing ? "" : cp + strlen (var->id);
-      const char *id = var->hidden_by ? var->hidden_by->id : var->id;
-      location id_loc = var->hidden_by ? var->hidden_by->loc : var->loc;
+      const char *id;
+      location id_loc;
+
+      if (var->hidden_by)
+        {
+          id = var->hidden_by->id;
+          id_loc = var->hidden_by->loc;
+        }
+      else
+        {
+          id = var->id;
+          id_loc = var->loc;
+        }
 
       /* Create the explanation message. */
       obstack_init (&msg_buf);
@@ -648,9 +584,6 @@ parse_ref (char *cp, symbol_list *rule, int rule_length,
         return INVALID_REF;
       }
     }
-
-  /* Not reachable. */
-  return INVALID_REF;
 }
 
 /* Keeps track of the maximum number of semantic values to the left of
@@ -671,7 +604,8 @@ fetch_type_name (char *cp, char const **type_name,
   if (*cp == '<')
     {
       *type_name = ++cp;
-      while (*cp != '>')
+      /* Series of non-'>' or "->".  */
+      while (*cp != '>' || cp[-1] == '-')
         ++cp;
 
       /* The '>' symbol will be later replaced by '\0'. Original

src/scan-gram.l

@@ -112,7 +112,12 @@ static void unexpected_newline (boundary, char const *);
  /* A identifier was just read in directives/rules.  Special state
     to capture the sequence 'identifier :'. */
 %x SC_AFTER_IDENTIFIER
- /* A complex tag, with nested angles brackets. */
+
+ /* POSIX says that a tag must be both an id and a C union member, but
+    historically almost any character is allowed in a tag.  We
+    disallow NUL, as this simplifies our implementation.  We match
+    angle brackets in nested pairs: several languages use them for
+    generics/template types.  */
 %x SC_TAG
 
  /* Four types of user code:
@@ -133,13 +138,6 @@ notletter [^.abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_]{-}[%\{]
 id        {letter}({letter}|[-0-9])*
 int       [0-9]+
 
-/* POSIX says that a tag must be both an id and a C union member, but
-   historically almost any character is allowed in a tag.  We disallow
-   NUL, as this simplifies our implementation.  We disallow angle
-   bracket to match them in nested pairs: several languages use them
-   for generics/template types.  */
-tag      [^\0<>]+
-
 /* Zero or more instances of backslash-newline.  Following GCC, allow
    white space between the backslash and the newline.  */
 splice   (\\[ \f\t\v]*\n)*
@@ -217,6 +215,7 @@ eqopt    ([[:space:]]*=)?
   "%defines"                        return PERCENT_DEFINES;
   "%destructor"                     return PERCENT_DESTRUCTOR;
   "%dprec"                          return PERCENT_DPREC;
+  "%empty"                          return PERCENT_EMPTY;
   "%error-verbose"                  return PERCENT_ERROR_VERBOSE;
   "%expect"                         return PERCENT_EXPECT;
   "%expect-rr"                      return PERCENT_EXPECT_RR;
@@ -267,7 +266,7 @@ eqopt    ([[:space:]]*=)?
   "%pure"[-_]"parser"               DEPRECATED("%pure-parser");
   "%token"[-_]"table"               DEPRECATED("%token-table");
 
-  "%"{id}|"%"{notletter}([[:graph:]])+ {
+  "%"{id} {
     complain (loc, complaint, _("invalid directive: %s"), quote (yytext));
   }
 
@@ -324,13 +323,6 @@ eqopt    ([[:space:]]*=)?
   /* A type. */
   "<*>"       return TAG_ANY;
   "<>"        return TAG_NONE;
-  "<"{tag}">" {
-    obstack_grow (&obstack_for_string, yytext + 1, yyleng - 2);
-    STRING_FINISH;
-    val->uniqstr = uniqstr_new (last_string);
-    STRING_FREE;
-    return TAG;
-  }
   "<"         {
     nesting = 0;
     token_start = loc->start;
@@ -520,7 +512,7 @@ eqopt    ([[:space:]]*=)?
   "\"" {
     STRING_FINISH;
     loc->start = token_start;
-    val->chars = last_string;
+    val->code = last_string;
     BEGIN INITIAL;
     return STRING;
   }
@@ -558,10 +550,11 @@ eqopt    ([[:space:]]*=)?
   <<EOF>>   unexpected_eof (token_start, "'");
 }
 
-  /*-----------------------------------------------------------.
-  | Scanning a Bison nested tag.  The initial angle bracket is |
-  | already eaten.                                             |
-  `-----------------------------------------------------------*/
+
+
+  /*--------------------------------------------------------------.
+  | Scanning a tag.  The initial angle bracket is already eaten.  |
+  `--------------------------------------------------------------*/
 
 <SC_TAG>
 {
@@ -579,7 +572,7 @@ eqopt    ([[:space:]]*=)?
     STRING_GROW;
   }
 
-  [^<>]+ STRING_GROW;
+  ([^<>]|->)+ STRING_GROW;
   "<"+   STRING_GROW; nesting += yyleng;
 
   <<EOF>>   unexpected_eof (token_start, ">");
@@ -758,7 +751,7 @@ eqopt    ([[:space:]]*=)?
   "%}" {
     STRING_FINISH;
     loc->start = code_start;
-    val->chars = last_string;
+    val->code = last_string;
     BEGIN INITIAL;
     return PROLOGUE;
   }
@@ -777,7 +770,7 @@ eqopt    ([[:space:]]*=)?
   <<EOF>> {
     STRING_FINISH;
     loc->start = code_start;
-    val->chars = last_string;
+    val->code = last_string;
     BEGIN INITIAL;
     return EPILOGUE;
   }

src/scan-skel.l

@@ -72,7 +72,7 @@ static void fail_for_invalid_at (char const *at);
 "@@" fputc ('@', yyout);
 "@{" fputc ('[', yyout);
 "@}" fputc (']', yyout);
-"@`" continue;  /* Used by b4_cat in ../data/bison.m4.  */
+"@'" continue;  /* Used by b4_cat in ../data/bison.m4.  */
 @\n  continue;
 
 "@oline@"  fprintf (yyout, "%d", out_lineno + 1);
@@ -83,7 +83,7 @@ static void fail_for_invalid_at (char const *at);
 "@output("      at_init (&argc, argv, &at_ptr, &at_output);
 
   /* This pattern must not match more than the previous @ patterns. */
-@[^@{}`(\n]*    fail_for_invalid_at (yytext);
+@[^@{}\'(\n]*   fail_for_invalid_at (yytext);
 \n              out_lineno++; ECHO;
 [^@\n]+         ECHO;
 
@@ -103,7 +103,7 @@ static void fail_for_invalid_at (char const *at);
   "@@"   obstack_1grow (&obstack_for_string, '@');
   "@{"   obstack_1grow (&obstack_for_string, '[');
   "@}"   obstack_1grow (&obstack_for_string, ']');
-  "@`"   continue; /* For starting an argument that begins with whitespace. */
+  "@'"   continue; /* For starting an argument that begins with whitespace. */
   @\n    continue;
 
   @[,)] {
@@ -183,6 +183,8 @@ flag (const char *arg)
   /* compare with values issued from b4_error */
   if (STREQ (arg, "complain"))
     return complaint;
+  else if (STREQ (arg, "deprecated"))
+    return Wdeprecated;
   else if (STREQ (arg, "fatal"))
     return fatal;
   else if (STREQ (arg, "note"))
@@ -242,8 +244,9 @@ at_output (int argc, char *argv[], char **out_namep, int *out_linenop)
       xfclose (yyout);
     }
   *out_namep = xstrdup (argv[1]);
-  output_file_name_check (out_namep);
-  yyout = xfopen (*out_namep, "w");
+  output_file_name_check (out_namep, true);
+  /* If there were errors, do not generate the output.  */
+  yyout = xfopen (complaint_status ? "/dev/null" : *out_namep, "w");
   *out_linenop = 1;
 }
 

src/symlist.c

@@ -36,18 +36,20 @@ symbol_list_sym_new (symbol *sym, location loc)
   res->content_type = SYMLIST_SYMBOL;
   res->content.sym = sym;
   res->location = res->sym_loc = loc;
+  res->named_ref = NULL;
 
   res->midrule = NULL;
   res->midrule_parent_rule = NULL;
   res->midrule_parent_rhs_index = 0;
 
-  code_props_none_init (&res->action_props);
-
+  /* Members used for LHS only.  */
   res->ruleprec = NULL;
+  res->percent_empty_loc = empty_location;
+  code_props_none_init (&res->action_props);
   res->dprec = 0;
+  res->dprec_location = empty_location;
   res->merger = 0;
-
-  res->named_ref = NULL;
+  res->merger_declaration_location = empty_location;
 
   res->next = NULL;
 
@@ -85,12 +87,17 @@ symbol_list_type_new (uniqstr type_name, location loc)
 void
 symbol_list_syms_print (const symbol_list *l, FILE *f)
 {
+  char const *sep = "";
   for (/* Nothing. */; l && l->content.sym; l = l->next)
     {
+      fputs (sep, f);
+      fputs (l->content_type == SYMLIST_SYMBOL ? "symbol: "
+             : l->content_type == SYMLIST_TYPE ? "type: "
+             : "invalid content_type: ",
+             f);
       symbol_print (l->content.sym, f);
-      fprintf (stderr, l->action_props.is_value_used ? " used" : " unused");
-      if (l && l->content.sym)
-        fprintf (f, ", ");
+      fputs (l->action_props.is_value_used ? " used" : " unused", f);
+      sep = ", ";
     }
 }
 

src/symlist.h

@@ -50,6 +50,9 @@ typedef struct symbol_list
   } content;
   location location;
 
+  /* Named reference. */
+  named_ref *named_ref;
+
   /* Proper location of the symbol, not all the rule */
   location sym_loc;
 
@@ -64,19 +67,26 @@ typedef struct symbol_list
   struct symbol_list *midrule_parent_rule;
   int midrule_parent_rhs_index;
 
+  /* ---------------------------------------------- */
+  /* Apply to the rule (attached to the LHS only).  */
+  /* ---------------------------------------------- */
+
+  /* Precedence/associativity.  */
+  symbol *ruleprec;
+
   /* The action is attached to the LHS of a rule, but action properties for
    * each RHS are also stored here.  */
   code_props action_props;
 
-  /* Precedence/associativity.  */
-  symbol *ruleprec;
+  /* The location of the first %empty for this rule, or \a
+     empty_location.  */
+  location percent_empty_loc;
+
   int dprec;
+  location dprec_location;
   int merger;
   location merger_declaration_location;
 
-  /* Named reference. */
-  named_ref *named_ref;
-
   /* The list.  */
   struct symbol_list *next;
 } symbol_list;

src/symtab.c

@@ -153,13 +153,13 @@ symbol_print (symbol const *s, FILE *f)
 {
   if (s)
     {
-      fprintf (f, "\"%s\"", s->tag);
+      fputs (s->tag, f);
       SYMBOL_ATTR_PRINT (type_name);
       SYMBOL_CODE_PRINT (destructor);
       SYMBOL_CODE_PRINT (printer);
     }
   else
-    fprintf (f, "<NULL>");
+    fputs ("<NULL>", f);
 }
 
 #undef SYMBOL_ATTR_PRINT
@@ -243,9 +243,12 @@ symbol_type_set (symbol *sym, uniqstr type_name, location loc)
     {
       if (sym->type_name)
         symbol_redeclaration (sym, "%type", sym->type_location, loc);
-      uniqstr_assert (type_name);
-      sym->type_name = type_name;
-      sym->type_location = loc;
+      else
+        {
+          uniqstr_assert (type_name);
+          sym->type_name = type_name;
+          sym->type_location = loc;
+        }
     }
 }
 
@@ -261,7 +264,8 @@ symbol_code_props_set (symbol *sym, code_props_type kind,
     symbol_redeclaration (sym, code_props_type_string (kind),
                           sym->props[kind].location,
                           code->location);
-  sym->props[kind] = *code;
+  else
+    sym->props[kind] = *code;
 }
 
 /*-----------------------------------------------------.
@@ -277,7 +281,8 @@ semantic_type_code_props_set (semantic_type *type,
     semantic_type_redeclaration (type, code_props_type_string (kind),
                                  type->props[kind].location,
                                  code->location);
-  type->props[kind] = *code;
+  else
+    type->props[kind] = *code;
 }
 
 /*---------------------------------------------------.
@@ -321,12 +326,15 @@ symbol_precedence_set (symbol *sym, int prec, assoc a, location loc)
 {
   if (a != undef_assoc)
     {
-      if (sym->prec != 0)
+      if (sym->prec)
         symbol_redeclaration (sym, assoc_to_string (a), sym->prec_location,
                               loc);
-      sym->prec = prec;
-      sym->assoc = a;
-      sym->prec_location = loc;
+      else
+        {
+          sym->prec = prec;
+          sym->assoc = a;
+          sym->prec_location = loc;
+        }
     }
 
   /* Only terminals have a precedence. */
@@ -360,7 +368,8 @@ symbol_class_set (symbol *sym, symbol_class class, location loc, bool declaring)
     {
       if (sym->status == declared && !warned)
         complain (&loc, Wother, _("symbol %s redeclared"), sym->tag);
-      sym->status = declared;
+      else
+        sym->status = declared;
     }
 }
 
@@ -441,7 +450,7 @@ semantic_type_check_defined (semantic_type *sem_type)
   /* <*> and <> do not have to be "declared".  */
   if (sem_type->status == declared
       || !*sem_type->tag
-      || STREQ(sem_type->tag, "*"))
+      || STREQ (sem_type->tag, "*"))
     {
       int i;
       for (i = 0; i < 2; ++i)
@@ -615,8 +624,8 @@ symbol_translation (symbol *this)
           (this->user_token_number,
            symbols[token_translations[this->user_token_number]],
            this);
-
-      token_translations[this->user_token_number] = this->number;
+      else
+        token_translations[this->user_token_number] = this->number;
     }
 
   return true;
@@ -1057,27 +1066,40 @@ register_precedence (graphid first, graphid snd)
 }
 
 
-/*--------------------------------------------------.
-| Print a warning for unused precedence relations.  |
-`--------------------------------------------------*/
+/*---------------------------------------.
+| Deep clear a linked / adjacency list). |
+`---------------------------------------*/
 
-void
-print_precedence_warnings (void)
+static void
+linkedlist_free (symgraphlink *node)
+{
+  if (node)
+    {
+      while (node->next)
+        {
+          symgraphlink *tmp = node->next;
+          free (node);
+          node = tmp;
+        }
+      free (node);
+    }
+}
+
+/*----------------------------------------------.
+| Clear and destroy association tracking table. |
+`----------------------------------------------*/
+
+static void
+assoc_free (void)
 {
   int i;
-  if (!prec_nodes)
-    init_prec_nodes ();
   for (i = 0; i < nsyms; ++i)
     {
-      symbol *s = symbols[i];
-      if (s
-          && s->prec != 0
-          && !prec_nodes[i]->pred
-          && !prec_nodes[i]->succ
-          && s->assoc == precedence_assoc)
-        complain (&s->location, Wother,
-                  _("useless precedence for %s"), s->tag);
+      linkedlist_free (prec_nodes[i]->pred);
+      linkedlist_free (prec_nodes[i]->succ);
+      free (prec_nodes[i]);
     }
+  free (prec_nodes);
 }
 
 /*---------------------------------------.
@@ -1088,7 +1110,7 @@ static void
 init_assoc (void)
 {
   graphid i;
-  used_assoc = xcalloc(nsyms, sizeof(*used_assoc));
+  used_assoc = xcalloc (nsyms, sizeof *used_assoc);
   for (i = 0; i < nsyms; ++i)
     used_assoc[i] = false;
 }
@@ -1119,21 +1141,37 @@ register_assoc (graphid i, graphid j)
   used_assoc[j] = true;
 }
 
-/*------------------------------------------------------.
-| Print a warning for each unused symbol associativity. |
-`------------------------------------------------------*/
+/*--------------------------------------------------.
+| Print a warning for unused precedence relations.  |
+`--------------------------------------------------*/
 
 void
-print_assoc_warnings (void)
+print_precedence_warnings (void)
 {
-  graphid i;
+  int i;
+  if (!prec_nodes)
+    init_prec_nodes ();
   if (!used_assoc)
     init_assoc ();
   for (i = 0; i < nsyms; ++i)
     {
       symbol *s = symbols[i];
-      if (is_assoc_useless (s))
-        complain (&s->location, Wother,
-                  _("useless associativity for %s"), s->tag);
+      if (s
+          && s->prec != 0
+          && !prec_nodes[i]->pred
+          && !prec_nodes[i]->succ)
+        {
+          if (is_assoc_useless (s))
+            complain (&s->prec_location, Wprecedence,
+                      _("useless precedence and associativity for %s"), s->tag);
+          else if (s->assoc == precedence_assoc)
+            complain (&s->prec_location, Wprecedence,
+                      _("useless precedence for %s"), s->tag);
+        }
+      else if (is_assoc_useless (s))
+        complain (&s->prec_location, Wprecedence,
+                  _("useless associativity for %s, use %%precedence"), s->tag);
     }
+  free (used_assoc);
+  assoc_free ();
 }

src/symtab.h

@@ -128,9 +128,9 @@ struct symbol
 /** Undefined user number.  */
 # define USER_NUMBER_UNDEFINED -1
 
-/* `symbol->user_token_number == USER_NUMBER_HAS_STRING_ALIAS' means
-   this symbol has a literal string alias.  For instance, `%token foo
-   "foo"' has `"foo"' numbered regularly, and `foo' numbered as
+/* 'symbol->user_token_number == USER_NUMBER_HAS_STRING_ALIAS' means
+   this symbol has a literal string alias.  For instance, '%token foo
+   "foo"' has '"foo"' numbered regularly, and 'foo' numbered as
    USER_NUMBER_HAS_STRING_ALIAS.  */
 # define USER_NUMBER_HAS_STRING_ALIAS -9991
 
@@ -266,7 +266,8 @@ struct symgraph
 
 void register_precedence (graphid first, graphid snd);
 
-/** Print a warning for each symbol whose precedence is useless. */
+/** Print a warning for each symbol whose precedence and/or associativity
+ * is useless. */
 
 void print_precedence_warnings (void);
 
@@ -274,9 +275,7 @@ void print_precedence_warnings (void);
 | Symbol associativity  |
 `----------------------*/
 
-void register_assoc (int i, int j);
-
-void print_assoc_warnings (void);
+void register_assoc (graphid i, graphid j);
 
 /*-----------------.
 | Semantic types.  |

src/system.h

@@ -99,7 +99,7 @@ typedef size_t uintptr_t;
 #  endif
 # endif
 
-/* The __-protected variants of `format' and `printf' attributes
+/* The __-protected variants of 'format' and 'printf' attributes
    are accepted by gcc versions 2.6.4 (effectively 2.7) and later.  */
 # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 7)
 #  define __format__ format

src/tables.c

@@ -35,7 +35,7 @@
 #include "tables.h"
 
 /* Several tables are indexed both by state and nonterminal numbers.
-   We call such an index a `vector'; i.e., a vector is either a state
+   We call such an index a 'vector'; i.e., a vector is either a state
    or a nonterminal number.
 
    Of course vector_number_t ought to be wide enough to contain
@@ -90,18 +90,18 @@ static base_number *width;
 
 /* For a given state, N = ACTROW[SYMBOL]:
 
-   If N = 0, stands for `run the default action'.
-   If N = MIN, stands for `raise a syntax error'.
-   If N > 0, stands for `shift SYMBOL and go to n'.
-   If N < 0, stands for `reduce -N'.  */
+   If N = 0, stands for 'run the default action'.
+   If N = MIN, stands for 'raise a syntax error'.
+   If N > 0, stands for 'shift SYMBOL and go to n'.
+   If N < 0, stands for 'reduce -N'.  */
 typedef int action_number;
 #define ACTION_NUMBER_MINIMUM INT_MIN
 
 static action_number *actrow;
 
 /* FROMS and TOS are reordered to be compressed.  ORDER[VECTOR] is the
-   new vector number of VECTOR.  We skip `empty' vectors (i.e.,
-   TALLY[VECTOR] = 0), and call these `entries'.  */
+   new vector number of VECTOR.  We skip 'empty' vectors (i.e.,
+   TALLY[VECTOR] = 0), and call these 'entries'.  */
 static vector_number *order;
 static int nentries;
 

src/uniqstr.c

@@ -77,7 +77,8 @@ uniqstr_vsprintf (char const *format, ...)
 void
 uniqstr_assert (char const *str)
 {
-  if (!hash_lookup (uniqstrs_table, str))
+  uniqstr s = hash_lookup (uniqstrs_table, str);
+  if (!s || s != str)
     {
       error (0, 0,
              "not a uniqstr: %s", quotearg (str));
@@ -105,7 +106,7 @@ uniqstr_print_processor (void *ustr, void *null ATTRIBUTE_UNUSED)
 
 
 int
-uniqstr_cmp(uniqstr l, uniqstr r)
+uniqstr_cmp (uniqstr l, uniqstr r)
 {
   return (l == r ? 0
           : !l ? -1

src/uniqstr.h

@@ -20,6 +20,8 @@
 #ifndef UNIQSTR_H_
 # define UNIQSTR_H_
 
+# include <stdio.h>
+
 /*-----------------------------------------.
 | Pointers to unique copies of C strings.  |
 `-----------------------------------------*/
@@ -33,14 +35,14 @@ uniqstr uniqstr_new (char const *str);
    strings, use UNIQSTR_CONCAT, which is a convenient wrapper around
    this function.  */
 uniqstr uniqstr_vsprintf (char const *format, ...)
-  __attribute__ ((__format__ (__printf__, 1, 2)));
+  _GL_ATTRIBUTE_FORMAT_PRINTF (1, 2);
 
 /* Two uniqstr values have the same value iff they are the same.  */
 # define UNIQSTR_EQ(Ustr1, Ustr2) (!!((Ustr1) == (Ustr2)))
 
 /* Compare two uniqstr a la strcmp: negative for <, nul for =, and
    positive for >.  Undefined order, relies on addresses.  */
-int uniqstr_cmp(uniqstr u1, uniqstr u2);
+int uniqstr_cmp (uniqstr u1, uniqstr u2);
 
 /* Die if STR is not a uniqstr.  */
 void uniqstr_assert (char const *str);

tests/actions.at

@@ -64,6 +64,119 @@ AT_PARSER_CHECK([./input], 0,
 
 AT_CLEANUP
 
+## ----------------------- ##
+## Implicitly empty rule.  ##
+## ----------------------- ##
+
+AT_SETUP([Implicitly empty rule])
+
+AT_DATA_GRAMMAR([[1.y]],
+[[%%
+exp: a b;
+a: /* empty. */ {};
+// A mid-rule action does not count as an empty rule.
+b: {} {};
+]])
+
+AT_BISON_CHECK([-fcaret -Wempty-rule 1.y], [0], [],
+[[1.y:11.17-18: warning: empty rule without %empty [-Wempty-rule]
+ a: /* empty. */ {};
+                 ^^
+]])
+
+AT_DATA_GRAMMAR([[2.y]],
+[[%%
+exp: a b c;
+a: /* empty. */ {};
+b: %empty       {};
+c: /* empty. */ {};
+]])
+
+AT_BISON_CHECK([-fcaret 2.y], [0], [],
+[[2.y:11.17-18: warning: empty rule without %empty [-Wempty-rule]
+ a: /* empty. */ {};
+                 ^^
+2.y:13.17-18: warning: empty rule without %empty [-Wempty-rule]
+ c: /* empty. */ {};
+                 ^^
+]])
+
+AT_BISON_CHECK([-fcaret -Wno-empty-rule 2.y], [0])
+
+AT_CLEANUP
+
+## ------------------------ ##
+## Invalid uses of %empty.  ##
+## ------------------------ ##
+
+AT_SETUP([Invalid uses of %empty])
+
+AT_DATA_GRAMMAR([[one.y]],
+[[%%
+exp:
+  %empty {} %empty
+;
+]])
+
+AT_BISON_CHECK([-fcaret one.y], [1], [],
+[[one.y:11.13-18: error: only one %empty allowed per rule
+   %empty {} %empty
+             ^^^^^^
+one.y:11.3-8: previous declaration
+   %empty {} %empty
+   ^^^^^^
+]])
+
+AT_DATA_GRAMMAR([[two.y]],
+[[%%
+exp:
+  'a' %empty    {}
+| %empty 'a'    {}
+| %empty {}     {}
+;
+]])
+
+AT_BISON_CHECK([-fcaret two.y], [1], [],
+[[two.y:11.7-12: error: %empty on non-empty rule
+   'a' %empty    {}
+       ^^^^^^
+two.y:12.3-8: error: %empty on non-empty rule
+ | %empty 'a'    {}
+   ^^^^^^
+two.y:13.3-8: error: %empty on non-empty rule
+ | %empty {}     {}
+   ^^^^^^
+]])
+
+AT_CLEANUP
+
+## ---------------------- ##
+## Valid uses of %empty.  ##
+## ---------------------- ##
+
+AT_SETUP([Valid uses of %empty])
+
+AT_BISON_OPTION_PUSHDEFS
+AT_DATA_GRAMMAR([[input.y]],
+[[
+%debug
+%code
+{
+]AT_YYERROR_DECLARE[
+]AT_YYLEX_DECLARE[
+}
+%%
+exp: %empty {}
+%%
+]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE[
+]AT_MAIN_DEFINE[
+]])
+
+AT_FULL_COMPILE([input])
+AT_PARSER_CHECK([./input])
+AT_BISON_OPTION_POPDEFS
+AT_CLEANUP
 
 ## ------------------ ##
 ## Initial location.  ##
@@ -173,8 +286,8 @@ m4_popdef([AT_TEST])
 ## Location Print.  ##
 ## ---------------- ##
 
-# AT_TEST(SKELETON-NAME, DIRECTIVES, [MORE-DIRECTIVES], [LOCATION = 1.1])
-# -----------------------------------------------------------------------
+# AT_TEST(SKELETON-NAME, DIRECTIVES, [MORE-DIRECTIVES])
+# -----------------------------------------------------
 # Check that the initial location is correct.
 m4_pushdef([AT_TEST],
 [AT_SETUP([Location print: $1 $2])
@@ -192,7 +305,7 @@ AT_DATA_GRAMMAR([[input.y]],
 ]AT_YYLEX_DECLARE[
 }
 %%
-exp: /* empty */;
+exp: %empty;
 %%
 ]AT_YYERROR_DEFINE[
 ]AT_YYLEX_DEFINE[
@@ -415,7 +528,7 @@ AT_LALR1_CC_IF([typedef yy::location YYLTYPE;])[
 %%
 /*
    This grammar is made to exercise error recovery.
-   "Lines" starting with `(' support error recovery, with
+   "Lines" starting with '(' support error recovery, with
    ')' as synchronizing token.  Lines starting with 'x' can never
    be recovered from if in error.
 */
@@ -483,7 +596,7 @@ thing:
 ;
 %%
 /* Alias to ARGV[1]. */
-const char *source = YY_NULL;
+const char *source = YY_NULLPTR;
 
 ]AT_YYERROR_DEFINE[
 
@@ -492,11 +605,11 @@ static
 {
   static unsigned int counter = 0;
 
-  int c = ]AT_VAL[]m4_ifval([$6], [.ival])[ = counter++;
+  unsigned int c = ]AT_VAL[]m4_ifval([$6], [.ival])[ = counter++;
   /* As in BASIC, line numbers go from 10 to 10.  */
   ]AT_LOC_FIRST_LINE[ = ]AT_LOC_FIRST_COLUMN[ = 10 * c;
   ]AT_LOC_LAST_LINE[ = ]AT_LOC_LAST_COLUMN[ = ]AT_LOC_FIRST_LINE[ + 9;
-  assert (0 <= c && c <= strlen (source));
+  assert (c <= strlen (source));
   if (source[c])
     fprintf (stderr, "sending: '%c'", source[c]);
   else
@@ -578,7 +691,7 @@ Successful parse.
 
 # Syntax errors caught by the parser
 # ----------------------------------
-# Exercise the discarding of stack top and input until `error'
+# Exercise the discarding of stack top and input until 'error'
 # can be reduced.
 #
 #     '(', 'x', 'x', 'x', 'x', 'x', ')',
@@ -735,13 +848,13 @@ AT_CLEANUP
 
 
 AT_CHECK_PRINTER_AND_DESTRUCTOR([])
-AT_CHECK_PRINTER_AND_DESTRUCTOR([], [with union])
+AT_CHECK_PRINTER_AND_DESTRUCTOR([], [ with union])
 
 AT_CHECK_PRINTER_AND_DESTRUCTOR([%defines %skeleton "lalr1.cc"])
-AT_CHECK_PRINTER_AND_DESTRUCTOR([%defines %skeleton "lalr1.cc"], [with union])
+AT_CHECK_PRINTER_AND_DESTRUCTOR([%defines %skeleton "lalr1.cc"], [ with union])
 
 AT_CHECK_PRINTER_AND_DESTRUCTOR([%glr-parser])
-AT_CHECK_PRINTER_AND_DESTRUCTOR([%glr-parser], [with union])
+AT_CHECK_PRINTER_AND_DESTRUCTOR([%glr-parser], [ with union])
 
 
 
@@ -1174,7 +1287,7 @@ AT_SETUP([Default %printer and %destructor are not for $accept])
 #   - The %printer and %destructor code generated for $accept would always be
 #     dead code because $accept is currently never shifted onto the stack.
 #   - $$ for $accept would always be of type YYSTYPE because it's not possible
-#     to declare `%type <field> $accept'.  (Also true for $undefined.)
+#     to declare '%type <field> $accept'.  (Also true for $undefined.)
 #   - Thus, the compiler might complain that the user code assumes the wrong
 #     type for $$ since the code might assume the type associated with a
 #     specific union field, which is especially reasonable in C++ since that
@@ -1494,115 +1607,6 @@ AT_TEST([glr.cc])
 
 m4_popdef([AT_TEST])
 
-## ----------------------------------------------- ##
-## Fix user actions without a trailing semicolon.  ##
-## ----------------------------------------------- ##
-
-AT_SETUP([[Fix user actions without a trailing semicolon]])
-
-# This feature is undocumented, but we accidentally broke it in 2.3a,
-# and there was a complaint at:
-# <http://lists.gnu.org/archive/html/bug-bison/2008-11/msg00001.html>.
-AT_BISON_OPTION_PUSHDEFS
-AT_DATA([input.y],
-[[%%
-start: test2 test1 test0 testc;
-
-test2
-: 'a' { semi;                   /* TEST:N:2 */ }
-| 'b' { if (0) {no_semi}        /* TEST:N:2 */ }
-| 'c' { if (0) {semi;}          /* TEST:N:2 */ }
-| 'd' { semi;   no_semi         /* TEST:Y:2 */ }
-| 'e' { semi(); no_semi()       /* TEST:Y:2 */ }
-| 'f' { semi[]; no_semi[]       /* TEST:Y:2 */ }
-| 'g' { semi++; no_semi++       /* TEST:Y:2 */ }
-| 'h' { {no_semi} no_semi       /* TEST:Y:2 */ }
-| 'i' { {semi;}   no_semi       /* TEST:Y:2 */ }
-;
-test1
-  : 'a' { semi;                 // TEST:N:1 ;
-} | 'b' { if (0) {no_semi}      // TEST:N:1 ;
-} | 'c' { if (0) {semi;}        // TEST:N:1 ;
-} | 'd' { semi;   no_semi       // TEST:Y:1 ;
-} | 'e' { semi(); no_semi()     // TEST:Y:1 ;
-} | 'f' { semi[]; no_semi[]     // TEST:Y:1 ;
-} | 'g' { semi++; no_semi++     // TEST:Y:1 ;
-} | 'h' { {no_semi} no_semi     // TEST:Y:1 ;
-} | 'i' { {semi;}   no_semi     // TEST:Y:1 ;
-} ;
-test0
-  : 'a' { semi;                 // TEST:N:1 {}
-} | 'b' { if (0) {no_semi}      // TEST:N:1 {}
-} | 'c' { if (0) {semi;}        // TEST:N:1 {}
-} | 'd' { semi;   no_semi       // TEST:Y:1 {}
-} | 'e' { semi(); no_semi()     // TEST:Y:1 {}
-} | 'f' { semi[]; no_semi[]     // TEST:Y:1 {}
-} | 'g' { semi++; no_semi++     // TEST:Y:1 {}
-} | 'h' { {no_semi} no_semi     // TEST:Y:1 {}
-} | 'i' { {semi;}   no_semi     // TEST:Y:1 {}
-} ;
-
-testc
-: 'a' {
-#define TEST_MACRO_N \
-[]"broken\" $ @ $$ @$ [];\
-string;"}
-| 'b' {
-no_semi
-#define TEST_MACRO_N \
-[]"broken\" $ @ $$ @$ [];\
-string;"}
-]])
-AT_BISON_OPTION_POPDEFS
-
-AT_BISON_CHECK([[-o input.c input.y]], [0], [],
-[[input.y:8.48: warning: a ';' might be needed at the end of action code [-Wdeprecated]
-input.y:8.48:     future versions of Bison will not add the ';'
-input.y:9.48: warning: a ';' might be needed at the end of action code [-Wdeprecated]
-input.y:9.48:     future versions of Bison will not add the ';'
-input.y:10.48: warning: a ';' might be needed at the end of action code [-Wdeprecated]
-input.y:10.48:     future versions of Bison will not add the ';'
-input.y:11.48: warning: a ';' might be needed at the end of action code [-Wdeprecated]
-input.y:11.48:     future versions of Bison will not add the ';'
-input.y:12.48: warning: a ';' might be needed at the end of action code [-Wdeprecated]
-input.y:12.48:     future versions of Bison will not add the ';'
-input.y:13.48: warning: a ';' might be needed at the end of action code [-Wdeprecated]
-input.y:13.48:     future versions of Bison will not add the ';'
-input.y:20.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
-input.y:20.1:     future versions of Bison will not add the ';'
-input.y:21.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
-input.y:21.1:     future versions of Bison will not add the ';'
-input.y:22.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
-input.y:22.1:     future versions of Bison will not add the ';'
-input.y:23.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
-input.y:23.1:     future versions of Bison will not add the ';'
-input.y:24.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
-input.y:24.1:     future versions of Bison will not add the ';'
-input.y:25.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
-input.y:25.1:     future versions of Bison will not add the ';'
-input.y:31.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
-input.y:31.1:     future versions of Bison will not add the ';'
-input.y:32.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
-input.y:32.1:     future versions of Bison will not add the ';'
-input.y:33.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
-input.y:33.1:     future versions of Bison will not add the ';'
-input.y:34.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
-input.y:34.1:     future versions of Bison will not add the ';'
-input.y:35.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
-input.y:35.1:     future versions of Bison will not add the ';'
-input.y:36.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
-input.y:36.1:     future versions of Bison will not add the ';'
-]])
-
-AT_MATCHES_CHECK([input.c], [[/\* TEST:N:2 \*/ \}$]],       [[3]])
-AT_MATCHES_CHECK([input.c], [[/\* TEST:Y:2 \*/ ;\}$]],      [[6]])
-AT_MATCHES_CHECK([input.c], [[// TEST:N:1 [;{}]*\n\}$]],    [[6]])
-AT_MATCHES_CHECK([input.c], [[// TEST:Y:1 [;{}]*\n;\}$]],  [[12]])
-AT_MATCHES_CHECK([input.c], [[#define TEST_MACRO_N \\\n\[\]"broken\\" \$ \@ \$\$ \@\$ \[\];\\\nstring;"\}]], [[2]])
-
-AT_CLEANUP
-
-
 ## -------------------------------------------------- ##
 ## Destroying lookahead assigned by semantic action.  ##
 ## -------------------------------------------------- ##
@@ -1637,7 +1641,7 @@ AT_DATA_GRAMMAR([input.y],
 // that has set yychar might not always return normally.  Instead,
 // skeletons must translate before every use of yytoken.
 start: 'a' accept { USE($1); } ;
-accept: /*empty*/ {
+accept: %empty {
   assert (yychar == YYEMPTY);
   yychar = 'b';
   YYACCEPT;

tests/atlocal.in

@@ -16,7 +16,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-# We need `config.h'.
+# We need 'config.h'.
 CPPFLAGS="-I$abs_top_builddir/lib @CPPFLAGS@"
 
 # Don't just check if $POSIXLY_CORRECT is set, as Bash, when launched
@@ -47,12 +47,39 @@ NO_WERROR_CXXFLAGS='@CXXFLAGS@ @WARN_CXXFLAGS@ @WARN_CXXFLAGS_TEST@'
   CFLAGS="$NO_WERROR_CFLAGS   @WERROR_CFLAGS@"
 CXXFLAGS="$NO_WERROR_CXXFLAGS @WERROR_CXXFLAGS@"
 
-# C++ variants break strict aliasing analysis.
-NO_STRICT_ALIAS_CXXFLAGS='@NO_STRICT_ALIAS_CXXFLAGS@'
-
 # If 'exit 77'; skip all C++ tests; otherwise ':'.
 BISON_CXX_WORKS='@BISON_CXX_WORKS@'
 
+# Be sure that the C++ compiler is not broken because of gnulib.  This
+# cannot be checked in configure (gnulib is not parameterized yet),
+# and checking this in every C++ test in AC_COMPILE_CXX is too costly.
+#
+# http://lists.gnu.org/archive/html/bug-bison/2013-06/msg00001.html
+#
+# FIXME: Check (say 2014) whether this is still needed.
+if $BISON_CXX_WORKS; then
+  # See AT_DATA_SOURCE_PROLOGUE.
+  cat >conftest.cc <<EOF
+#include <config.h>
+/* We don't need perfect functions for these tests. */
+#undef malloc
+#undef memcmp
+#undef realloc
+#include <iostream>
+
+int main ()
+{
+  std::cout << "Works" << std::endl;
+}
+EOF
+  $CXX $CXXFLAGS $CPPFLAGS $LDFLAGS $LIBS -o conftest conftest.cc
+  case $? in
+   0);;
+   *) BISON_CXX_WORKS="as_fn_error 77 cannot-compile-simple-program";;
+  esac
+  rm -fr conftest*
+fi
+
 # Whether the compiler supports POSIXLY_CORRECT defined.
 : ${C_COMPILER_POSIXLY_CORRECT='@C_COMPILER_POSIXLY_CORRECT@'}
 : ${CXX_COMPILER_POSIXLY_CORRECT='@CXX_COMPILER_POSIXLY_CORRECT@'}

tests/c++.at

@@ -18,6 +18,68 @@
 AT_BANNER([[C++ Features.]])
 
 
+## --------------- ##
+## C++ Locations.  ##
+## --------------- ##
+
+AT_SETUP([C++ Locations])
+
+AT_BISON_OPTION_PUSHDEFS([%locations %skeleton "lalr1.cc"])
+AT_DATA_GRAMMAR([[input.y]],
+[[%code {#include <sstream>}
+%locations
+%debug
+%skeleton "lalr1.cc"
+%code
+{
+]AT_YYERROR_DECLARE[
+]AT_YYLEX_DECLARE[
+}
+%%
+exp: %empty;
+%%
+]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE[
+
+template <typename T>
+bool
+check (const T& in, const std::string& s)
+{
+  std::stringstream os;
+  os << in;
+  if (os.str () != s)
+    {
+      std::cerr << "fail: " << os.str () << ", expected: " << s << std::endl;
+      return false;
+    }
+  return true;
+}
+
+int
+main (void)
+{
+  int fail = 0;
+  ]AT_YYLTYPE[ loc;  fail += check (loc, "1.1");
+  loc += 10;         fail += check (loc, "1.1-10");
+  loc += -5;         fail += check (loc, "1.1-5");
+  loc -= 5;          fail += check (loc, "1.1");
+  // Check that we don't go below.
+  // http://lists.gnu.org/archive/html/bug-bison/2013-02/msg00000.html
+  loc -= 10;         fail += check (loc, "1.1");
+
+  loc.columns (10); loc.lines (10); fail += check (loc, "1.1-11.0");
+  loc.lines (-2);                   fail += check (loc, "1.1-9.0");
+  loc.lines (-10);                  fail += check (loc, "1.1");
+  return !fail;
+}
+]])
+
+AT_FULL_COMPILE([input])
+AT_PARSER_CHECK([./input], 0)
+AT_BISON_OPTION_POPDEFS
+AT_CLEANUP
+
+
 ## --------------------------- ##
 ## C++ Variant-based Symbols.  ##
 ## --------------------------- ##
@@ -28,7 +90,7 @@ AT_KEYWORDS([variant])
 
 AT_BISON_OPTION_PUSHDEFS([%skeleton "lalr1.cc" %debug $1])
 # Store strings and integers in a list of strings.
-AT_DATA_GRAMMAR([list.yy],
+AT_DATA_GRAMMAR([list.y],
 [[%skeleton "lalr1.cc"
 %define api.value.type variant
 %define parse.assert
@@ -92,8 +154,7 @@ int main()
 }
 ]])
 
-AT_BISON_CHECK([-o list.cc list.yy])
-AT_COMPILE_CXX([list], [$NO_STRICT_ALIAS_CXXFLAGS list.cc])
+AT_FULL_COMPILE([list])
 AT_PARSER_CHECK([./list], 0, [],
 [12
 123
@@ -113,11 +174,10 @@ AT_CLEANUP
 m4_pushdef([AT_TEST],
 [AT_SETUP([Variants $1])
 
-AT_BISON_OPTION_PUSHDEFS([%skeleton "lalr1.cc" %debug $1])
+AT_BISON_OPTION_PUSHDEFS([%debug $1])
 # Store strings and integers in a list of strings.
-AT_DATA_GRAMMAR([list.yy],
+AT_DATA_GRAMMAR([list.y],
 [[%debug
-%skeleton "lalr1.cc"
 %define api.value.type variant
 ]m4_bpatsubst([$1], [\\n], [
 ])[
@@ -183,7 +243,7 @@ typedef std::list<std::string> strings_type;
 // digraph for the left square bracket.
 %type <::std::list<std::string>> list result;
 
-%printer { yyo << $][$; }
+%printer { yyo << $$; }
   <int> <::std::string> <::std::list<std::string>>;
 %%
 
@@ -193,13 +253,13 @@ result:
 
 list:
   /* nothing */ { /* Generates an empty string list */ }
-| list item     { std::swap ($][$,$][1); $$.push_back ($][2); }
-| list error    { std::swap ($][$,$][1); }
+| list item     { std::swap ($$,$][1); $$.push_back ($][2); }
+| list error    { std::swap ($$,$][1); }
 ;
 
 item:
-  TEXT          { std::swap ($][$,$][1); }
-| NUMBER        { if ($][1 == 3) YYERROR; else $][$ = string_cast ($][1); }
+  TEXT          { std::swap ($$,$][1); }
+| NUMBER        { if ($][1 == 3) YYERROR; else $$ = string_cast ($][1); }
 ;
 %%
 ]AT_TOKEN_CTOR_IF([],
@@ -250,8 +310,7 @@ namespace yy
 ]AT_MAIN_DEFINE[
 ]])
 
-AT_BISON_CHECK([-o list.cc list.yy])
-AT_COMPILE_CXX([list], [$NO_STRICT_ALIAS_CXXFLAGS list.cc])
+AT_FULL_COMPILE([list])
 AT_PARSER_CHECK([./list], 0,
 [(0, 1, 2, 4)
 ])
@@ -260,13 +319,13 @@ AT_BISON_OPTION_POPDEFS
 AT_CLEANUP
 ])
 
-AT_TEST([])
-AT_TEST([%define parse.assert])
-AT_TEST([%locations %define parse.assert])
-AT_TEST([[%define parse.assert %code {\n#define TWO_STAGE_BUILD\n}]])
-AT_TEST([[%define parse.assert %define api.token.constructor]])
-AT_TEST([[%define parse.assert %define api.token.constructor %define api.token.prefix "TOK_"]])
-AT_TEST([[%locations %define parse.assert %define api.token.constructor %define api.token.prefix "TOK_"]])
+AT_TEST([[%skeleton "lalr1.cc" ]])
+AT_TEST([[%skeleton "lalr1.cc" %define parse.assert]])
+AT_TEST([[%skeleton "lalr1.cc" %locations %define parse.assert]])
+AT_TEST([[%skeleton "lalr1.cc" %define parse.assert %code {\n#define TWO_STAGE_BUILD\n}]])
+AT_TEST([[%skeleton "lalr1.cc" %define parse.assert %define api.token.constructor]])
+AT_TEST([[%skeleton "lalr1.cc" %define parse.assert %define api.token.constructor %define api.token.prefix {TOK_}]])
+AT_TEST([[%skeleton "lalr1.cc" %locations %define parse.assert %define api.token.constructor %define api.token.prefix {TOK_}]])
 
 m4_popdef([AT_TEST])
 
@@ -363,10 +422,10 @@ AT_CHECK_DOXYGEN([Private])
 # is specified, then Bison should accept the input, but compilation will fail,
 # so don't check compilation.
 m4_pushdef([AT_TEST],
-[AT_BISON_OPTION_PUSHDEFS([%language "C++" %define api.namespace "$1"])
+[AT_BISON_OPTION_PUSHDEFS([%language "C++" %define api.namespace {$1}])
 AT_DATA_GRAMMAR([[input.y]],
 [[%language "C++"
-%define api.namespace "]$1["
+%define api.namespace {]$1[}
 %union { int i; }
 %define global_tokens_and_yystype
 %locations
@@ -422,8 +481,8 @@ AT_CLEANUP
 AT_SETUP([[Syntactically invalid namespace references]])
 AT_TEST([[:foo:bar]], [[-]])
 AT_TEST([[foo: :bar]], [[-]])
-# This one is interesting because `[3]' is encoded as `@<:@3@:>@', which
-# contains single occurrences of `:'.
+# This one is interesting because '[3]' is encoded as '@<:@3@:>@', which
+# contains single occurrences of ':'.
 AT_TEST([[foo[3]::bar::baz]], [[-]])
 AT_TEST([[foo::bar,baz]], [[-]])
 AT_TEST([[foo::bar::(baz /* Pacify Emacs ) */]], [[-]])
@@ -590,11 +649,14 @@ AT_CLEANUP
 ## Exception safety.  ##
 ## ------------------ ##
 
-# AT_TEST([BISON-DIRECTIVES])
-# ---------------------------
+# AT_TEST([BISON-DIRECTIVES = ''], [WITH-RECOVERY = "with"])
+# ----------------------------------------------------------
 # Check that no object is leaked when exceptions are thrown.
+# WITH-RECOVERY = "with" or "without".
 m4_pushdef([AT_TEST],
-[AT_SETUP([[Exception safety $1]])
+[AT_SETUP([[Exception safety $2 error recovery $1]])
+
+AT_SKIP_IF_EXCEPTION_SUPPORT_IS_POOR
 
 AT_BISON_OPTION_PUSHDEFS([%skeleton "lalr1.cc" $1])
 
@@ -608,21 +670,59 @@ $1
   #include <cassert>
   #include <cstdlib> // size_t and getenv.
   #include <iostream>
-  #include <list>
+  #include <set>
 
   bool debug = false;
 
-  /// A class that counts its number of instances.
+  /// A class that tracks its instances.
   struct Object
   {
-    typedef std::list<const Object*> objects;
-    static objects instances;
     char val;
 
+    Object ()
+      : val ('?')
+    {
+      log (this, "Object::Object");
+      Object::instances.insert (this);
+    }
+
+    Object (const Object& that)
+      : val (that.val)
+    {
+      log (this, "Object::Object");
+      Object::instances.insert (this);
+    }
+
+    Object (char v)
+      : val (v)
+    {
+      log (this, "Object::Object");
+      Object::instances.insert (this);
+    }
+
+    ~Object ()
+    {
+      log (this, "Object::~Object");
+      objects::const_iterator i = instances.find (this);
+      // Make sure this object is alive.
+      assert (i != instances.end ());
+      Object::instances.erase (i);
+    }
+
+    Object& operator= (char v)
+    {
+      val = v;
+      return *this;
+    }
+
+    // Static part.
+    typedef std::set<const Object*> objects;
+    static objects instances;
+
     static bool
     empty ()
     {
-      return instances.empty();
+      return instances.empty ();
     }
 
     static void
@@ -645,26 +745,6 @@ $1
           std::cerr << " }" << std::endl;
         }
     }
-
-    Object (char v)
-      : val (v)
-    {
-      instances.push_back(this);
-      log (this, "Object::Object");
-    }
-
-    Object ()
-      : val ('?')
-    {
-      instances.push_back(this);
-      log (this, "Object::Object");
-    }
-
-    ~Object ()
-    {
-      instances.remove(this);
-      log (this, "Object::~Object");
-    }
   };
 }
 
@@ -716,22 +796,23 @@ $1
 start: list {]AT_VARIANT_IF([], [ delete $][1]; )[};
 
 list:
-  item       { $][$ = $][1; }
+  item       { $$ = $][1; }
   // Right recursion to load the stack.
-| item list  { $][$ = $][1; ]AT_VARIANT_IF([], [delete $][2]; )[}
+| item list  { $$ = $][1; ]AT_VARIANT_IF([], [delete $][2]; )[}
 ;
 
 item:
-  'a'  { $$][ = $][1; }
-| 'e'  { YYUSE ($][$); YYUSE($][1); error ("syntax error"); }
+  'a'     { $$ = $][1; }
+| 'e'     { YYUSE ($$); YYUSE($][1); error ("syntax error"); }
 // Not just 'E', otherwise we reduce when 'E' is the lookahead, and
 // then the stack is emptied, defeating the point of the test.
-| 'E' 'a' { YYUSE($][1); $][$ = $][2; }
-| 'R'  { $][$ = YY_NULL; ]AT_VARIANT_IF([], [delete $][1]; )[YYERROR; }
-| 'p'  { $][$ = $][1; }
-| 's'  { $][$ = $][1; throw std::runtime_error ("reduction"); }
-| 'T'  { $][$ = YY_NULL; ]AT_VARIANT_IF([], [delete $][1]; )[YYABORT; }
-| error { $][$ = YY_NULL; yyerrok; }
+| 'E' 'a' { YYUSE($][1); $$ = $][2; }
+| 'R'     { ]AT_VARIANT_IF([], [$$ = YY_NULLPTR; delete $][1]; )[YYERROR; }
+| 'p'     { $$ = $][1; }
+| 's'     { $$ = $][1; throw std::runtime_error ("reduction"); }
+| 'T'     { ]AT_VARIANT_IF([], [$$ = YY_NULLPTR; delete $][1]; )[YYABORT; }
+]m4_if([$2], [with],
+[[| error   { $$ = ]AT_VARIANT_IF([], [new ])[Object ('R'); yyerrok; }]])[
 ;
 %%
 
@@ -751,7 +832,8 @@ yylex (yy::parser::semantic_type *lvalp)
   case 'l':
     throw std::runtime_error ("yylex");
   default:
-    lvalp]AT_VARIANT_IF([->build (res)], [->obj = new Object (res)])[;
+    lvalp->]AT_VARIANT_IF([build (Object (res))],
+                          [obj = new Object (res)])[;
     // Fall through.
   case 0:
     return res;
@@ -798,13 +880,13 @@ main (int argc, const char *argv[])
   {
     std::cerr << "unknown exception caught" << std::endl;
   }
-  Object::log (YY_NULL, "end");
+  Object::log (YY_NULLPTR, "end");
   assert (Object::empty());
   return res;
 }
 ]])
 AT_BISON_CHECK([[-o input.cc --report=all input.yy]])
-AT_COMPILE_CXX([input], [[$NO_STRICT_ALIAS_CXXFLAGS input.cc]])
+AT_COMPILE_CXX([[input]])
 
 AT_PARSER_CHECK([[./input aaaas]], [[2]], [[]],
 [[exception caught: reduction
@@ -833,16 +915,17 @@ AT_PARSER_CHECK([[./input aaaaE]], [[2]], [[]],
 
 AT_PARSER_CHECK([[./input aaaaT]], [[1]])
 
-# There is error-recovery, so exit success.
-AT_PARSER_CHECK([[./input aaaaR]], [[0]])
+AT_PARSER_CHECK([[./input aaaaR]], [m4_if([$2], [with], [0], [1])])
 
 AT_BISON_OPTION_POPDEFS
 
 AT_CLEANUP
 ])
 
-AT_TEST
-AT_TEST([%define api.value.type variant])
+AT_TEST([], [with])
+AT_TEST([], [without])
+AT_TEST([%define api.value.type variant], [with])
+AT_TEST([%define api.value.type variant], [without])
 
 m4_popdef([AT_TEST])
 

tests/calc.at

@@ -27,11 +27,11 @@
 
 # _AT_DATA_CALC_Y($1, $2, $3, [BISON-DIRECTIVES])
 # -----------------------------------------------
-# Produce `calc.y' and, if %defines was specified, `calc-lex.c' or
-# `calc-lex.cc'.
+# Produce 'calc.y' and, if %defines was specified, 'calc-lex.c' or
+# 'calc-lex.cc'.
 #
 # Don't call this macro directly, because it contains some occurrences
-# of `$1' etc. which will be interpreted by m4.  So you should call it
+# of '$1' etc. which will be interpreted by m4.  So you should call it
 # with $1, $2, and $3 as arguments, which is what AT_DATA_CALC_Y does.
 #
 # When %defines is not passed, generate a single self-contained file.
@@ -72,10 +72,12 @@ main (int argc, const char **argv)
   int count = 0;
   int status;
 
-  /* This used to be alarm (10), but that isn't enough time for
-     a July 1995 vintage DEC Alphastation 200 4/100 system,
-     according to Nelson H. F. Beebe.  100 seconds is enough.  */
-  alarm (100);
+  /* This used to be alarm (10), but that isn't enough time for a July
+     1995 vintage DEC Alphastation 200 4/100 system, according to
+     Nelson H. F. Beebe.  100 seconds was enough for regular users,
+     but the Hydra build farm, which is heavily loaded needs more.  */
+
+  alarm (200);
 
   if (argc == 2)
     input = fopen (argv[1], "r");
@@ -88,8 +90,7 @@ main (int argc, const char **argv)
       return 3;
     }
 
-]AT_SKEL_CC_IF([], [m4_bmatch([$4], [%debug],
-[  ]AT_NAME_PREFIX[debug = 1;])])[
+]AT_SKEL_CC_IF([], [AT_DEBUG_IF([  ]AT_NAME_PREFIX[debug = 1;])])[
   status = ]AT_NAME_PREFIX[parse (]AT_PARAM_IF([[&result, &count]])[);
   if (fclose (input))
     perror ("fclose");
@@ -133,7 +134,7 @@ unget_char (]AT_YYLEX_PRE_FORMALS[ int c)
 {
   ]AT_USE_LEX_ARGS[;
 ]AT_LOCATION_IF([
-  /* Wrong when C == `\n'. */
+  /* Wrong when C == '\n'. */
   AT_LOC = last_yylloc;
 ])[
   ungetc (c, input);
@@ -365,8 +366,8 @@ m4_popdef([AT_CALC_LEX])
 
 # AT_DATA_CALC_Y([BISON-OPTIONS])
 # -------------------------------
-# Produce `calc.y' and, if %defines was specified, `calc-lex.c' or
-# `calc-lex.cc'.
+# Produce 'calc.y' and, if %defines was specified, 'calc-lex.c' or
+# 'calc-lex.cc'.
 m4_define([AT_DATA_CALC_Y],
 [_AT_DATA_CALC_Y($[1], $[2], $[3], [$1])
 ])
@@ -375,9 +376,9 @@ m4_define([AT_DATA_CALC_Y],
 
 # _AT_CHECK_CALC(BISON-OPTIONS, INPUT, [NUM-STDERR-LINES])
 # --------------------------------------------------------
-# Run `calc' on INPUT and expect no STDOUT nor STDERR.
+# Run 'calc' on INPUT and expect no STDOUT nor STDERR.
 #
-# If BISON-OPTIONS contains `%debug' but not `%glr-parser', then
+# If BISON-OPTIONS contains '%debug' but not '%glr-parser', then
 #
 # NUM-STDERR-LINES is the number of expected lines on stderr.
 # Currently this is ignored, though, since the output format is fluctuating.
@@ -396,7 +397,7 @@ AT_PARSER_CHECK([./calc input], 0, [], [stderr])
 #                      [NUM-STDERR-LINES],
 #                      [VERBOSE-AND-LOCATED-ERROR-MESSAGE])
 # ---------------------------------------------------------
-# Run `calc' on INPUT, and expect a `syntax error' message.
+# Run 'calc' on INPUT, and expect a 'syntax error' message.
 #
 # If INPUT starts with a slash, it is used as absolute input file name,
 # otherwise as contents.
@@ -404,14 +405,14 @@ AT_PARSER_CHECK([./calc input], 0, [], [stderr])
 # NUM-STDERR-LINES is the number of expected lines on stderr.
 # Currently this is ignored, though, since the output format is fluctuating.
 #
-# If BISON-OPTIONS contains `%location', then make sure the ERROR-LOCATION
+# If BISON-OPTIONS contains '%location', then make sure the ERROR-LOCATION
 # is correctly output on stderr.
 #
-# If BISON-OPTIONS contains `%define parse.error verbose', then make sure the
-# IF-YYERROR-VERBOSE message is properly output after `syntax error, '
+# If BISON-OPTIONS contains '%define parse.error verbose', then make sure the
+# IF-YYERROR-VERBOSE message is properly output after 'syntax error, '
 # on STDERR.
 #
-# If BISON-OPTIONS contains `%debug' but not `%glr', then NUM-STDERR-LINES
+# If BISON-OPTIONS contains '%debug' but not '%glr', then NUM-STDERR-LINES
 # is the number of expected lines on stderr.
 m4_define([_AT_CHECK_CALC_ERROR],
 [m4_bmatch([$3], [^/],
@@ -448,7 +449,7 @@ AT_DATA([[expout]],
 AT_YYERROR_SEES_LOC_IF([],
 [[sed 's/^[-0-9.]*: //' expout >at-expout
 mv at-expout expout]])
-# 4. If error-verbose is not used, strip the`, unexpected....' part.
+# 4. If error-verbose is not used, strip the', unexpected....' part.
 m4_bmatch([$1], [%define parse.error verbose], [],
 [[sed 's/syntax error, .*$/syntax error/' expout >at-expout
 mv at-expout expout]])
@@ -478,7 +479,7 @@ m4_define([AT_CHECK_SPACES],
 
 # AT_CHECK_CALC([BISON-OPTIONS])
 # ------------------------------
-# Start a testing chunk which compiles `calc' grammar with
+# Start a testing chunk which compiles 'calc' grammar with
 # BISON-OPTIONS, and performs several tests over the parser.
 m4_define([AT_CHECK_CALC],
 [m4_ifval([$2], [m4_fatal([$0: expected a single argument])])
@@ -538,7 +539,7 @@ _AT_CHECK_CALC_ERROR([$1], [1], [/dev/null], [4],
 #   - (* * *): nothing to pop, a lot to discard
 #   - (1 + 2 * *): some to pop and discard
 #
-# - test the action associated to `error'
+# - test the action associated to 'error'
 #
 # - check the lookahead that triggers an error is not discarded
 #   when we enter error recovery.  Below, the lookahead causing the
@@ -587,7 +588,7 @@ AT_BANNER([[Simple LALR(1) Calculator.]])
 
 # AT_CHECK_CALC_LALR([BISON-OPTIONS])
 # -----------------------------------
-# Start a testing chunk which compiles `calc' grammar with
+# Start a testing chunk which compiles 'calc' grammar with
 # BISON-OPTIONS, and performs several tests over the parser.
 m4_define([AT_CHECK_CALC_LALR],
 [AT_CHECK_CALC($@)])
@@ -606,17 +607,17 @@ AT_CHECK_CALC_LALR([%define api.pure full %locations])
 AT_CHECK_CALC_LALR([%define api.push-pull both %define api.pure full %locations])
 AT_CHECK_CALC_LALR([%define parse.error verbose %locations])
 
-AT_CHECK_CALC_LALR([%define parse.error verbose %locations %defines %define api.prefix "calc" %verbose %yacc])
-AT_CHECK_CALC_LALR([%define parse.error verbose %locations %defines %name-prefix "calc" %define api.token.prefix "TOK_" %verbose %yacc])
+AT_CHECK_CALC_LALR([%define parse.error verbose %locations %defines %define api.prefix {calc} %verbose %yacc])
+AT_CHECK_CALC_LALR([%define parse.error verbose %locations %defines %name-prefix "calc" %define api.token.prefix {TOK_} %verbose %yacc])
 
 AT_CHECK_CALC_LALR([%debug])
 AT_CHECK_CALC_LALR([%define parse.error verbose %debug %locations %defines %name-prefix "calc" %verbose %yacc])
-AT_CHECK_CALC_LALR([%define parse.error verbose %debug %locations %defines %define api.prefix "calc" %verbose %yacc])
+AT_CHECK_CALC_LALR([%define parse.error verbose %debug %locations %defines %define api.prefix {calc} %verbose %yacc])
 
 AT_CHECK_CALC_LALR([%define api.pure full %define parse.error verbose %debug %locations %defines %name-prefix "calc" %verbose %yacc])
-AT_CHECK_CALC_LALR([%define api.push-pull both %define api.pure full %define parse.error verbose %debug %locations %defines %define api.prefix "calc" %verbose %yacc])
+AT_CHECK_CALC_LALR([%define api.push-pull both %define api.pure full %define parse.error verbose %debug %locations %defines %define api.prefix {calc} %verbose %yacc])
 
-AT_CHECK_CALC_LALR([%define api.pure %define parse.error verbose %debug %locations %defines %define api.prefix "calc" %verbose %yacc %parse-param {semantic_value *result} %parse-param {int *count}])
+AT_CHECK_CALC_LALR([%define api.pure %define parse.error verbose %debug %locations %defines %define api.prefix {calc} %verbose %yacc %parse-param {semantic_value *result} %parse-param {int *count}])
 
 
 # ----------------------- #
@@ -627,7 +628,7 @@ AT_BANNER([[Simple GLR Calculator.]])
 
 # AT_CHECK_CALC_GLR([BISON-OPTIONS])
 # ----------------------------------
-# Start a testing chunk which compiles `calc' grammar with
+# Start a testing chunk which compiles 'calc' grammar with
 # BISON-OPTIONS and %glr-parser, and performs several tests over the parser.
 m4_define([AT_CHECK_CALC_GLR],
 [AT_CHECK_CALC([%glr-parser] $@)])
@@ -638,7 +639,7 @@ AT_CHECK_CALC_GLR()
 AT_CHECK_CALC_GLR([%defines])
 AT_CHECK_CALC_GLR([%locations])
 AT_CHECK_CALC_GLR([%name-prefix "calc"])
-AT_CHECK_CALC_GLR([%define api.prefix "calc"])
+AT_CHECK_CALC_GLR([%define api.prefix {calc}])
 AT_CHECK_CALC_GLR([%verbose])
 AT_CHECK_CALC_GLR([%yacc])
 AT_CHECK_CALC_GLR([%define parse.error verbose])
@@ -650,12 +651,12 @@ AT_CHECK_CALC_GLR([%define parse.error verbose %locations %defines %name-prefix
 
 AT_CHECK_CALC_GLR([%debug])
 AT_CHECK_CALC_GLR([%define parse.error verbose %debug %locations %defines %name-prefix "calc" %verbose %yacc])
-AT_CHECK_CALC_GLR([%define parse.error verbose %debug %locations %defines %define api.prefix "calc" %define api.token.prefix "TOK_" %verbose %yacc])
+AT_CHECK_CALC_GLR([%define parse.error verbose %debug %locations %defines %define api.prefix {calc} %define api.token.prefix {TOK_} %verbose %yacc])
 
 AT_CHECK_CALC_GLR([%define api.pure %define parse.error verbose %debug %locations %defines %name-prefix "calc" %verbose %yacc])
 
 AT_CHECK_CALC_GLR([%define api.pure %define parse.error verbose %debug %locations %defines %name-prefix "calc" %verbose %yacc %parse-param {semantic_value *result} %parse-param {int *count}])
-AT_CHECK_CALC_GLR([%define api.pure %define parse.error verbose %debug %locations %defines %define api.prefix "calc" %verbose %yacc %parse-param {semantic_value *result} %parse-param {int *count}])
+AT_CHECK_CALC_GLR([%define api.pure %define parse.error verbose %debug %locations %defines %define api.prefix {calc} %verbose %yacc %parse-param {semantic_value *result} %parse-param {int *count}])
 
 
 # ----------------------------- #
@@ -669,26 +670,26 @@ AT_CHECK_CALC([%skeleton "lalr1.cc" %defines])
 
 # AT_CHECK_CALC_LALR1_CC([BISON-OPTIONS])
 # ---------------------------------------
-# Start a testing chunk which compiles `calc' grammar with
+# Start a testing chunk which compiles 'calc' grammar with
 # the C++ skeleton, and performs several tests over the parser.
 m4_define([AT_CHECK_CALC_LALR1_CC],
 [AT_CHECK_CALC([%language "C++"] $@)])
 
 AT_CHECK_CALC_LALR1_CC([])
 AT_CHECK_CALC_LALR1_CC([%locations])
-AT_CHECK_CALC_LALR1_CC([%locations %define api.location.type Span])
+AT_CHECK_CALC_LALR1_CC([%locations %define api.location.type {Span}])
 AT_CHECK_CALC_LALR1_CC([%defines %locations %define parse.error verbose %name-prefix "calc" %verbose %yacc])
 
-AT_CHECK_CALC_LALR1_CC([%locations %define parse.error verbose %define api.prefix "calc" %verbose %yacc])
+AT_CHECK_CALC_LALR1_CC([%locations %define parse.error verbose %define api.prefix {calc} %verbose %yacc])
 AT_CHECK_CALC_LALR1_CC([%locations %define parse.error verbose %debug %name-prefix "calc" %verbose %yacc])
 
-AT_CHECK_CALC_LALR1_CC([%locations %pure-parser %define parse.error verbose %debug %define api.prefix "calc" %verbose %yacc])
-AT_CHECK_CALC_LALR1_CC([%locations %pure-parser %define parse.error verbose %debug %define api.prefix "calc" %define api.token.prefix "TOK_" %verbose %yacc])
+AT_CHECK_CALC_LALR1_CC([%locations %define parse.error verbose %debug %define api.prefix {calc} %verbose %yacc])
+AT_CHECK_CALC_LALR1_CC([%locations %define parse.error verbose %debug %define api.prefix {calc} %define api.token.prefix {TOK_} %verbose %yacc])
 
-AT_CHECK_CALC_LALR1_CC([%defines %locations %pure-parser %define parse.error verbose %debug %name-prefix "calc" %verbose %yacc %parse-param {semantic_value *result} %parse-param {int *count}])
+AT_CHECK_CALC_LALR1_CC([%defines %locations %define parse.error verbose %debug %name-prefix "calc" %verbose %yacc %parse-param {semantic_value *result} %parse-param {int *count}])
 
-AT_CHECK_CALC_LALR1_CC([%pure-parser %define parse.error verbose %debug %define api.prefix "calc" %verbose %yacc %parse-param {semantic_value *result} %parse-param {int *count}])
-AT_CHECK_CALC_LALR1_CC([%defines %locations %pure-parser %define parse.error verbose %debug %define api.prefix "calc" %verbose %yacc %parse-param {semantic_value *result} %parse-param {int *count}])
+AT_CHECK_CALC_LALR1_CC([%define parse.error verbose %debug %define api.prefix {calc} %verbose %yacc %parse-param {semantic_value *result} %parse-param {int *count}])
+AT_CHECK_CALC_LALR1_CC([%defines %locations %define parse.error verbose %debug %define api.prefix {calc} %verbose %yacc %parse-param {semantic_value *result} %parse-param {int *count}])
 
 
 
@@ -703,22 +704,21 @@ AT_CHECK_CALC([%skeleton "glr.cc"])
 
 # AT_CHECK_CALC_GLR_CC([BISON-OPTIONS])
 # -------------------------------------
-# Start a testing chunk which compiles `calc' grammar with
+# Start a testing chunk which compiles 'calc' grammar with
 # the GLR C++ skeleton, and performs several tests over the parser.
 m4_define([AT_CHECK_CALC_GLR_CC],
 [AT_CHECK_CALC([%language "C++" %glr-parser] $@)])
 
 AT_CHECK_CALC_GLR_CC([])
 AT_CHECK_CALC_GLR_CC([%locations])
-AT_CHECK_CALC_GLR_CC([%locations %define api.location.type Span])
+AT_CHECK_CALC_GLR_CC([%locations %define api.location.type {Span}])
 AT_CHECK_CALC_GLR_CC([%defines %define parse.error verbose %name-prefix "calc" %verbose %yacc])
-AT_CHECK_CALC_GLR_CC([%define parse.error verbose %define api.prefix "calc" %verbose %yacc])
+AT_CHECK_CALC_GLR_CC([%define parse.error verbose %define api.prefix {calc} %verbose %yacc])
 
 AT_CHECK_CALC_GLR_CC([%debug])
+
 AT_CHECK_CALC_GLR_CC([%define parse.error verbose %debug %name-prefix "calc" %verbose %yacc])
+AT_CHECK_CALC_GLR_CC([%define parse.error verbose %debug %name-prefix "calc" %define api.token.prefix {TOK_} %verbose %yacc])
 
-AT_CHECK_CALC_GLR_CC([%pure-parser %define parse.error verbose %debug %name-prefix "calc" %verbose %yacc])
-AT_CHECK_CALC_GLR_CC([%pure-parser %define parse.error verbose %debug %name-prefix "calc" %define api.token.prefix "TOK_" %verbose %yacc])
-
-AT_CHECK_CALC_GLR_CC([%locations %defines %pure-parser %define parse.error verbose %debug %name-prefix "calc" %verbose %yacc %parse-param {semantic_value *result} %parse-param {int *count}])
-AT_CHECK_CALC_GLR_CC([%locations %defines %pure-parser %define parse.error verbose %debug %define api.prefix "calc" %verbose %yacc %parse-param {semantic_value *result} %parse-param {int *count}])
+AT_CHECK_CALC_GLR_CC([%locations %defines %define parse.error verbose %debug %name-prefix "calc" %verbose %yacc %parse-param {semantic_value *result} %parse-param {int *count}])
+AT_CHECK_CALC_GLR_CC([%locations %defines %define parse.error verbose %debug %define api.prefix {calc} %verbose %yacc %parse-param {semantic_value *result} %parse-param {int *count}])

tests/conflicts.at

@@ -17,42 +17,9 @@
 
 AT_BANNER([[Conflicts.]])
 
-## ------------------------------ ##
-## Useless associativity warning. ##
-## ------------------------------ ##
-
-AT_SETUP([Useless associativity warning])
-
-AT_DATA([[input.y]],
-[[%token T
-%left A B
-%right C
-%nonassoc D
-%precedence E
-
-%%
-e: T A T
- | T B T
- | T C T
- | T D T
- | T E T
-;
-]])
-
-AT_BISON_CHECK([input.y], 0, [],
-[[input.y:5.13: warning: useless precedence for E [-Wother]
-input.y:2.7: warning: useless associativity for A [-Wother]
-input.y:2.9: warning: useless associativity for B [-Wother]
-input.y:3.8: warning: useless associativity for C [-Wother]
-input.y:4.11: warning: useless associativity for D [-Wother]
-]])
-
-AT_CLEANUP
-
-
-## ------------------------ ##
-## Token declaration order. ##
-## ------------------------ ##
+## ------------------------- ##
+## Token declaration order.  ##
+## ------------------------- ##
 
 # This test checks that token are declared left to right when in a precedence
 # statement.
@@ -110,27 +77,7 @@ int main (void)
 }
 ]])
 
-AT_BISON_CHECK([-o input.c input.y], [], [],
-[[input.y:24.13: warning: useless precedence for R [-Wother]
-input.y:24.15: warning: useless precedence for S [-Wother]
-input.y:24.17: warning: useless precedence for T [-Wother]
-input.y:24.19: warning: useless precedence for U [-Wother]
-input.y:25.13: warning: useless precedence for V [-Wother]
-input.y:25.15: warning: useless precedence for W [-Wother]
-input.y:18.8: warning: useless associativity for E [-Wother]
-input.y:18.10: warning: useless associativity for F [-Wother]
-input.y:18.12: warning: useless associativity for G [-Wother]
-input.y:19.8: warning: useless associativity for H [-Wother]
-input.y:19.10: warning: useless associativity for I [-Wother]
-input.y:20.8: warning: useless associativity for J [-Wother]
-input.y:21.8: warning: useless associativity for K [-Wother]
-input.y:22.8: warning: useless associativity for L [-Wother]
-input.y:22.10: warning: useless associativity for M [-Wother]
-input.y:22.12: warning: useless associativity for N [-Wother]
-input.y:23.11: warning: useless associativity for O [-Wother]
-input.y:23.13: warning: useless associativity for P [-Wother]
-input.y:23.15: warning: useless associativity for Q [-Wother]
-]])
+AT_BISON_CHECK([-o input.c input.y])
 AT_COMPILE([input])
 
 AT_PARSER_CHECK([./input])
@@ -140,6 +87,127 @@ AT_BISON_OPTION_POPDEFS
 AT_CLEANUP
 
 
+## --------------------------------------------------- ##
+## Token declaration order: literals vs. identifiers.  ##
+## --------------------------------------------------- ##
+
+# This test checks that when several tokens are declared by the same keyword,
+# some of them defined as a character ('a'), others as simple textual reference
+# (A), they are declared correctly left to right.
+# Previously, the following test would declare the states in the order 'o' 'p'
+# M N, instead of M N 'o' 'p'.
+
+AT_SETUP([Token declaration order: literals vs. identifiers])
+
+AT_DATA_GRAMMAR([[input.y]],
+[[%token 'a' 'b' C D
+%token E F 'g' 'h'
+%right 'i' 'j' K L
+%right M N 'o' 'p'
+%%
+exp: 'a'
+   | 'b'
+   | C
+   | D
+   | E
+   | F
+   | 'g'
+   | 'h'
+   | 'i'
+   | 'j'
+   | K
+   | L
+   | M
+   | N
+   | 'o'
+   | 'p'
+;
+%%
+]])
+
+AT_BISON_CHECK([[--report=all -o input.c input.y]], 0, [], [ignore])
+AT_CHECK([[cat input.output | sed -n '/^State 0$/,/^State 1$/p']], 0,
+[[State 0
+
+    0 $accept: . exp $end
+    1 exp: . 'a'
+    2    | . 'b'
+    3    | . C
+    4    | . D
+    5    | . E
+    6    | . F
+    7    | . 'g'
+    8    | . 'h'
+    9    | . 'i'
+   10    | . 'j'
+   11    | . K
+   12    | . L
+   13    | . M
+   14    | . N
+   15    | . 'o'
+   16    | . 'p'
+
+    'a'  shift, and go to state 1
+    'b'  shift, and go to state 2
+    C    shift, and go to state 3
+    D    shift, and go to state 4
+    E    shift, and go to state 5
+    F    shift, and go to state 6
+    'g'  shift, and go to state 7
+    'h'  shift, and go to state 8
+    'i'  shift, and go to state 9
+    'j'  shift, and go to state 10
+    K    shift, and go to state 11
+    L    shift, and go to state 12
+    M    shift, and go to state 13
+    N    shift, and go to state 14
+    'o'  shift, and go to state 15
+    'p'  shift, and go to state 16
+
+    exp  go to state 17
+
+
+State 1
+]])
+
+AT_CLEANUP
+
+
+## ------------------------------- ##
+## Useless associativity warning.  ##
+## ------------------------------- ##
+
+AT_SETUP([Useless associativity warning])
+
+AT_DATA([[input.y]],
+[[%token EQ "=" PL "+" ST "*"  LP "("
+%nonassoc "="
+%left "+"
+%left "*"
+%precedence "("
+%%
+stmt:
+  exp
+| "var" "=" exp
+;
+
+exp:
+  exp "+" exp
+| exp "*" "num"
+| "(" exp ")"
+| "num"
+;
+]])
+
+AT_BISON_CHECK([-Wprecedence input.y], 0, [],
+[[input.y:2.1-9: warning: useless precedence and associativity for "=" [-Wprecedence]
+input.y:4.1-5: warning: useless associativity for "*", use %precedence [-Wprecedence]
+input.y:5.1-11: warning: useless precedence for "(" [-Wprecedence]
+]])
+
+AT_CLEANUP
+
+
 ## ---------------------------- ##
 ## Useless precedence warning.  ##
 ## ---------------------------- ##
@@ -147,7 +215,7 @@ AT_CLEANUP
 AT_SETUP([Useless precedence warning])
 
 AT_DATA([[input.y]],
-[[%token A B
+[[%token A B U V W X Y Z
 %precedence Z
 %left X
 %precedence Y
@@ -174,19 +242,19 @@ f: B
 ;
 ]])
 
-AT_BISON_CHECK([-fcaret -o input.c input.y], 0, [],
-[[input.y:2.13: warning: useless precedence for Z [-Wother]
- %precedence Z
-             ^
-input.y:5.7: warning: useless associativity for W [-Wother]
- %left W
-       ^
-input.y:6.8: warning: useless associativity for V [-Wother]
- %right V
-        ^
-input.y:7.11: warning: useless associativity for U [-Wother]
+AT_BISON_CHECK([-Wprecedence -fcaret -o input.c input.y], 0, [],
+[[input.y:7.1-9: warning: useless precedence and associativity for U [-Wprecedence]
  %nonassoc U
-           ^
+ ^^^^^^^^^
+input.y:6.1-6: warning: useless precedence and associativity for V [-Wprecedence]
+ %right V
+ ^^^^^^
+input.y:5.1-5: warning: useless precedence and associativity for W [-Wprecedence]
+ %left W
+ ^^^^^
+input.y:2.1-11: warning: useless precedence for Z [-Wprecedence]
+ %precedence Z
+ ^^^^^^^^^^^
 ]])
 
 AT_CLEANUP
@@ -211,7 +279,7 @@ e: 'e' | /* Nothing. */;
 ]])
 
 AT_BISON_CHECK([-o input.c input.y], 0, [],
-[[input.y:4.9: warning: rule useless in parser due to conflicts: e: /* empty */ [-Wother]
+[[input.y:4.9: warning: rule useless in parser due to conflicts [-Wother]
 ]])
 
 AT_BISON_CHECK([-fcaret -o input.c input.y], 0, [],
@@ -939,7 +1007,7 @@ cond:
 
 AT_BISON_CHECK([-o input.c input.y], 0, [],
 [[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
-input.y:12.3-18: warning: rule useless in parser due to conflicts: cond: cond "then" cond [-Wother]
+input.y:12.3-18: warning: rule useless in parser due to conflicts [-Wother]
 ]])
 
 AT_CLEANUP
@@ -955,13 +1023,13 @@ AT_CLEANUP
 #    $end           reduce using rule 3 (num)
 #    $end           [reduce using rule 4 (id)]
 #
-# But when `reduce 3' is the default action, we'd produce:
+# But when 'reduce 3' is the default action, we'd produce:
 #
 #    $end           [reduce using rule 4 (id)]
 #    $default    reduce using rule 3 (num)
 #
 # In this precise case (a reduction is masked by the default
-# reduction), we make the `reduce 3' explicit:
+# reduction), we make the 'reduce 3' explicit:
 #
 #    $end           reduce using rule 3 (num)
 #    $end           [reduce using rule 4 (id)]
@@ -983,7 +1051,7 @@ id : '0';
 
 AT_BISON_CHECK([-o input.c --report=all input.y], 0, [],
 [[input.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
-input.y:4.6-8: warning: rule useless in parser due to conflicts: id: '0' [-Wother]
+input.y:4.6-8: warning: rule useless in parser due to conflicts [-Wother]
 ]])
 
 # Check the contents of the report.
@@ -1196,10 +1264,10 @@ e:   e '+' e
    ;
 ]])
 
-AT_BISON_CHECK([-o input.c input.y], 0, [],
+AT_BISON_CHECK([-Wall -o input.c input.y], 0, [],
 [[input.y: warning: 4 shift/reduce conflicts [-Wconflicts-sr]
-input.y:1.7-9: warning: useless associativity for '+' [-Wother]
-input.y:2.7-9: warning: useless associativity for '*' [-Wother]
+input.y:1.1-5: warning: useless precedence and associativity for '+' [-Wprecedence]
+input.y:2.1-5: warning: useless precedence and associativity for '*' [-Wprecedence]
 ]])
 AT_CLEANUP
 
@@ -1303,13 +1371,13 @@ reported_conflicts:
 AT_BISON_CHECK([[--report=all input.y]], 0, [],
 [[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
 input.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
-input.y:12.5-20: warning: rule useless in parser due to conflicts: resolved_conflict: 'a' unreachable1 [-Wother]
-input.y:20.5-20: warning: rule useless in parser due to conflicts: unreachable1: 'a' unreachable2 [-Wother]
-input.y:21.4: warning: rule useless in parser due to conflicts: unreachable1: /* empty */ [-Wother]
-input.y:25.13: warning: rule useless in parser due to conflicts: unreachable2: /* empty */ [-Wother]
-input.y:25.16: warning: rule useless in parser due to conflicts: unreachable2: /* empty */ [-Wother]
-input.y:31.5-7: warning: rule useless in parser due to conflicts: reported_conflicts: 'a' [-Wother]
-input.y:32.4: warning: rule useless in parser due to conflicts: reported_conflicts: /* empty */ [-Wother]
+input.y:12.5-20: warning: rule useless in parser due to conflicts [-Wother]
+input.y:20.5-20: warning: rule useless in parser due to conflicts [-Wother]
+input.y:21.4: warning: rule useless in parser due to conflicts [-Wother]
+input.y:25.13: warning: rule useless in parser due to conflicts [-Wother]
+input.y:25.16: warning: rule useless in parser due to conflicts [-Wother]
+input.y:31.5-7: warning: rule useless in parser due to conflicts [-Wother]
+input.y:32.4: warning: rule useless in parser due to conflicts [-Wother]
 ]])
 
 AT_CHECK([[cat input.output]], 0,
@@ -1318,13 +1386,13 @@ AT_CHECK([[cat input.output]], 0,
     2 resolved_conflict: 'a' unreachable1
 
     4 unreachable1: 'a' unreachable2
-    5             | /* empty */
+    5             | %empty
 
-    6 unreachable2: /* empty */
-    7             | /* empty */
+    6 unreachable2: %empty
+    7             | %empty
 
     9 reported_conflicts: 'a'
-   10                   | /* empty */
+   10                   | %empty
 
 
 State 4 conflicts: 1 shift/reduce
@@ -1338,17 +1406,17 @@ Grammar
     1 start: resolved_conflict 'a' reported_conflicts 'a'
 
     2 resolved_conflict: 'a' unreachable1
-    3                  | /* empty */
+    3                  | %empty
 
     4 unreachable1: 'a' unreachable2
-    5             | /* empty */
+    5             | %empty
 
-    6 unreachable2: /* empty */
-    7             | /* empty */
+    6 unreachable2: %empty
+    7             | %empty
 
     8 reported_conflicts: 'a'
     9                   | 'a'
-   10                   | /* empty */
+   10                   | %empty
 
 
 Terminals, with rules where they appear
@@ -1379,7 +1447,7 @@ State 0
     0 $accept: . start $end
     1 start: . resolved_conflict 'a' reported_conflicts 'a'
     2 resolved_conflict: . 'a' unreachable1
-    3                  | .  ['a']
+    3                  | . %empty  ['a']
 
     $default  reduce using rule 3 (resolved_conflict)
 
@@ -1415,7 +1483,7 @@ State 4
     1 start: resolved_conflict 'a' . reported_conflicts 'a'
     8 reported_conflicts: . 'a'
     9                   | . 'a'
-   10                   | .  ['a']
+   10                   | . %empty  ['a']
 
     'a'  shift, and go to state 5
 
@@ -1456,10 +1524,10 @@ AT_CHECK([[cat input.y >> input-keep.y]])
 AT_BISON_CHECK([[input-keep.y]], 0, [],
 [[input-keep.y: warning: 2 shift/reduce conflicts [-Wconflicts-sr]
 input-keep.y: warning: 2 reduce/reduce conflicts [-Wconflicts-rr]
-input-keep.y:22.4: warning: rule useless in parser due to conflicts: unreachable1: /* empty */ [-Wother]
-input-keep.y:26.16: warning: rule useless in parser due to conflicts: unreachable2: /* empty */ [-Wother]
-input-keep.y:32.5-7: warning: rule useless in parser due to conflicts: reported_conflicts: 'a' [-Wother]
-input-keep.y:33.4: warning: rule useless in parser due to conflicts: reported_conflicts: /* empty */ [-Wother]
+input-keep.y:22.4: warning: rule useless in parser due to conflicts [-Wother]
+input-keep.y:26.16: warning: rule useless in parser due to conflicts [-Wother]
+input-keep.y:32.5-7: warning: rule useless in parser due to conflicts [-Wother]
+input-keep.y:33.4: warning: rule useless in parser due to conflicts [-Wother]
 ]])
 
 AT_CLEANUP
@@ -1508,11 +1576,11 @@ AT_CHECK([[cat input.output | sed -n '/^State 0$/,/^State 1$/p']], 0,
     6      | . empty_c1 'c'
     7      | . empty_c2 'c'
     8      | . empty_c3 'c'
-    9 empty_a: .  ['a']
-   10 empty_b: .  []
-   11 empty_c1: .  []
-   12 empty_c2: .  []
-   13 empty_c3: .  ['c']
+    9 empty_a: . %empty  ['a']
+   10 empty_b: . %empty  []
+   11 empty_c1: . %empty  []
+   12 empty_c2: . %empty  []
+   13 empty_c3: . %empty  ['c']
 
     'b'  shift, and go to state 1
 
@@ -1584,11 +1652,11 @@ AT_CHECK([[cat input.output | sed -n '/^State 0$/,/^State 1$/p']], 0,
     6      | . empty_c1 'c'
     7      | . empty_c2 'c'
     8      | . empty_c3 'c'
-    9 empty_a: .  []
-   10 empty_b: .  []
-   11 empty_c1: .  []
-   12 empty_c2: .  ['c']
-   13 empty_c3: .  ['c']
+    9 empty_a: . %empty  []
+   10 empty_b: . %empty  []
+   11 empty_c1: . %empty  []
+   12 empty_c2: . %empty  ['c']
+   13 empty_c3: . %empty  ['c']
 
     'a'  error (nonassociative)
     'b'  error (nonassociative)
@@ -1639,7 +1707,7 @@ exp: 'a' | 'a';
 AT_BISON_CHECK([[2.y]], [[0]], [],
 [[2.y: warning: %expect-rr applies only to GLR parsers [-Wother]
 2.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
-2.y:3.12-14: warning: rule useless in parser due to conflicts: exp: 'a' [-Wother]
+2.y:3.12-14: warning: rule useless in parser due to conflicts [-Wother]
 ]])
 
 AT_CLEANUP

tests/cxx-type.at

@@ -94,19 +94,19 @@ prog :
 
 stmt : expr ';'  $2     { $$ = ]$[1; }
      | decl      $3
-     | error ';'        { $$ = new_nterm ("<error>", YY_NULL, YY_NULL, YY_NULL); }
+     | error ';'        { $$ = new_nterm ("<error>", YY_NULLPTR, YY_NULLPTR, YY_NULLPTR); }
      | '@'              { YYACCEPT; }
      ;
 
 expr : ID
      | TYPENAME '(' expr ')'
-                        { $$ = new_nterm ("<cast>(%s,%s)", ]$[3, ]$[1, YY_NULL); }
-     | expr '+' expr    { $$ = new_nterm ("+(%s,%s)", ]$[1, ]$[3, YY_NULL); }
-     | expr '=' expr    { $$ = new_nterm ("=(%s,%s)", ]$[1, ]$[3, YY_NULL); }
+                        { $$ = new_nterm ("<cast>(%s,%s)", ]$[3, ]$[1, YY_NULLPTR); }
+     | expr '+' expr    { $$ = new_nterm ("+(%s,%s)", ]$[1, ]$[3, YY_NULLPTR); }
+     | expr '=' expr    { $$ = new_nterm ("=(%s,%s)", ]$[1, ]$[3, YY_NULLPTR); }
      ;
 
 decl : TYPENAME declarator ';'
-                        { $$ = new_nterm ("<declare>(%s,%s)", ]$[1, ]$[2, YY_NULL); }
+                        { $$ = new_nterm ("<declare>(%s,%s)", ]$[1, ]$[2, YY_NULLPTR); }
      | TYPENAME declarator '=' expr ';'
                         { $$ = new_nterm ("<init-declare>(%s,%s,%s)", ]$[1,
                                           ]$[2, ]$[4); }
@@ -195,7 +195,7 @@ main (int argc, char **argv)
               {
                 colNum += 1;
                 tok = c;
-                yylval = YY_NULL;
+                yylval = YY_NULLPTR;
               }]AT_LOCATION_IF([[
             yylloc.last_column = colNum-1;]])[
             return tok;
@@ -287,7 +287,7 @@ m4_bmatch([$2], [stmtMerge],
 [[static YYSTYPE
 stmtMerge (YYSTYPE x0, YYSTYPE x1)
 {
-  return new_nterm ("<OR>(%s,%s)", x0, x1, YY_NULL);
+  return new_nterm ("<OR>(%s,%s)", x0, x1, YY_NULLPTR);
 }
 ]])
 )

tests/existing.at

@@ -403,68 +403,60 @@ dnl parses it as:
 dnl
 dnl   getline $!(4*0);
 dnl
-dnl That is, they shift `*' immediately and make it part of the getline
+dnl That is, they shift '*' immediately and make it part of the getline
 dnl argument.
 dnl
 dnl The grammar below using LALR(1) parses it as a syntax error.  So does
 dnl GNU AWK 3.0.6, 3.1.0, and 3.1.1.  They reduce the full getline expression
-dnl before shifting `*' even though `*' is not a valid lookahead.
+dnl before shifting '*' even though '*' is not a valid lookahead.
 dnl
 dnl GNU AWK 3.1.2, 3.1.3, 3.1.4, and 3.1.5 parse it as:
 dnl
 dnl   (getline $!4)*0;
 dnl
 dnl That is, like the other versions of GNU AWK, they reduce the full getline
-dnl expression before shifting `*'.  However, because of a different LHS on the
-dnl getline rule, `*' actually is a valid lookahead.  Solaris /usr/xpg4/bin/awk
+dnl expression before shifting '*'.  However, because of a different LHS on the
+dnl getline rule, '*' actually is a valid lookahead.  Solaris /usr/xpg4/bin/awk
 dnl and the Open Group awk specification seem to agree:
 dnl
 dnl   http://www.opengroup.org/pubs/online/7908799/xcu/awk.html
 dnl
 dnl /bin/nawk and /bin/awk on Solaris 10 report it as a syntax error, but they
-dnl don't like even `print $!4;'.
+dnl don't like even 'print $!4;'.
 [[LEX_GETLINE, '$', '!', YNUMBER, '*', YNUMBER, ';']],
 
 dnl BISON-STDERR
-[AT_COND_CASE([[canonical LR]],
-[[input.y: warning: 265 shift/reduce conflicts [-Wconflicts-sr]
-input.y:19.8-16: warning: useless associativity for FUNC_CALL [-Wother]
-input.y:21.8-14: warning: useless associativity for YNUMBER [-Wother]
-input.y:21.16-22: warning: useless associativity for YSTRING [-Wother]
-input.y:22.14-22: warning: useless associativity for APPEND_OP [-Wother]
-input.y:23.8-15: warning: useless associativity for ASSIGNOP [-Wother]
-input.y:23.33-41: warning: useless associativity for CONCAT_OP [-Wother]
-input.y:27.8-18: warning: useless associativity for LEX_GETLINE [-Wother]
-input.y:28.8-13: warning: useless associativity for LEX_IN [-Wother]
-input.y:29.23-31: warning: useless associativity for INCREMENT [-Wother]
-input.y:29.33-41: warning: useless associativity for DECREMENT [-Wother]
-input.y:30.8-18: warning: useless associativity for LEX_BUILTIN [-Wother]
-input.y:30.20-29: warning: useless associativity for LEX_LENGTH [-Wother]
-input.y:40.11-13: warning: useless associativity for ',' [-Wother]
-input.y:47.8-10: warning: useless associativity for '!' [-Wother]
-input.y:47.12-16: warning: useless associativity for UNARY [-Wother]
-input.y:50.7-9: warning: useless associativity for '$' [-Wother]
-input.y:51.7-9: warning: useless associativity for '(' [-Wother]
-input.y:51.11-13: warning: useless associativity for ')' [-Wother]]],
-[[input.y: warning: 65 shift/reduce conflicts [-Wconflicts-sr]
-input.y:19.8-16: warning: useless associativity for FUNC_CALL [-Wother]
-input.y:21.8-14: warning: useless associativity for YNUMBER [-Wother]
-input.y:21.16-22: warning: useless associativity for YSTRING [-Wother]
-input.y:22.14-22: warning: useless associativity for APPEND_OP [-Wother]
-input.y:23.8-15: warning: useless associativity for ASSIGNOP [-Wother]
-input.y:23.33-41: warning: useless associativity for CONCAT_OP [-Wother]
-input.y:27.8-18: warning: useless associativity for LEX_GETLINE [-Wother]
-input.y:28.8-13: warning: useless associativity for LEX_IN [-Wother]
-input.y:29.23-31: warning: useless associativity for INCREMENT [-Wother]
-input.y:29.33-41: warning: useless associativity for DECREMENT [-Wother]
-input.y:30.8-18: warning: useless associativity for LEX_BUILTIN [-Wother]
-input.y:30.20-29: warning: useless associativity for LEX_LENGTH [-Wother]
-input.y:40.11-13: warning: useless associativity for ',' [-Wother]
-input.y:47.8-10: warning: useless associativity for '!' [-Wother]
-input.y:47.12-16: warning: useless associativity for UNARY [-Wother]
-input.y:50.7-9: warning: useless associativity for '$' [-Wother]
-input.y:51.7-9: warning: useless associativity for '(' [-Wother]
-input.y:51.11-13: warning: useless associativity for ')' [-Wother]]])[
+[[input.y:66.10: warning: empty rule without %empty [-Wempty-rule]
+input.y:169.8: warning: empty rule without %empty [-Wempty-rule]
+input.y:174.12: warning: empty rule without %empty [-Wempty-rule]
+input.y:179.13: warning: empty rule without %empty [-Wempty-rule]
+input.y:187.15: warning: empty rule without %empty [-Wempty-rule]
+input.y:201.8: warning: empty rule without %empty [-Wempty-rule]
+input.y:206.21: warning: empty rule without %empty [-Wempty-rule]
+input.y:220.20: warning: empty rule without %empty [-Wempty-rule]
+input.y:299.13: warning: empty rule without %empty [-Wempty-rule]
+input.y:322.9: warning: empty rule without %empty [-Wempty-rule]
+]AT_COND_CASE([[canonical LR]],
+[[input.y: warning: 265 shift/reduce conflicts [-Wconflicts-sr]]],
+[[input.y: warning: 65 shift/reduce conflicts [-Wconflicts-sr]]])[
+input.y:39.1-5: warning: useless associativity for FUNC_CALL, use %precedence [-Wprecedence]
+input.y:44.1-5: warning: useless associativity for YNUMBER, use %precedence [-Wprecedence]
+input.y:44.1-5: warning: useless associativity for YSTRING, use %precedence [-Wprecedence]
+input.y:42.1-9: warning: useless precedence and associativity for APPEND_OP [-Wprecedence]
+input.y:33.1-6: warning: useless associativity for ASSIGNOP, use %precedence [-Wprecedence]
+input.y:43.1-5: warning: useless associativity for CONCAT_OP, use %precedence [-Wprecedence]
+input.y:37.1-5: warning: useless precedence and associativity for LEX_GETLINE [-Wprecedence]
+input.y:38.1-9: warning: useless associativity for LEX_IN, use %precedence [-Wprecedence]
+input.y:49.1-5: warning: useless associativity for INCREMENT, use %precedence [-Wprecedence]
+input.y:49.1-5: warning: useless associativity for DECREMENT, use %precedence [-Wprecedence]
+input.y:39.1-5: warning: useless associativity for LEX_BUILTIN, use %precedence [-Wprecedence]
+input.y:39.1-5: warning: useless associativity for LEX_LENGTH, use %precedence [-Wprecedence]
+input.y:40.1-9: warning: useless precedence and associativity for ',' [-Wprecedence]
+input.y:47.1-6: warning: useless associativity for '!', use %precedence [-Wprecedence]
+input.y:47.1-6: warning: useless associativity for UNARY, use %precedence [-Wprecedence]
+input.y:50.1-5: warning: useless associativity for '$', use %precedence [-Wprecedence]
+input.y:51.1-5: warning: useless associativity for '(', use %precedence [-Wprecedence]
+input.y:51.1-5: warning: useless precedence and associativity for ')' [-Wprecedence]
 ]],
 
 dnl LAST-STATE
@@ -1403,23 +1395,39 @@ dnl INPUT
 [[]],
 
 dnl BISON-STDERR
-[AT_COND_CASE([[canonical LR]],
+[[input.y:128.12: warning: empty rule without %empty [-Wempty-rule]
+input.y:137.10: warning: empty rule without %empty [-Wempty-rule]
+input.y:142.8: warning: empty rule without %empty [-Wempty-rule]
+input.y:161.15: warning: empty rule without %empty [-Wempty-rule]
+input.y:179.17: warning: empty rule without %empty [-Wempty-rule]
+input.y:205.16: warning: empty rule without %empty [-Wempty-rule]
+input.y:213.9: warning: empty rule without %empty [-Wempty-rule]
+input.y:225.6: warning: empty rule without %empty [-Wempty-rule]
+input.y:292.18: warning: empty rule without %empty [-Wempty-rule]
+input.y:294.19: warning: empty rule without %empty [-Wempty-rule]
+input.y:367.16: warning: empty rule without %empty [-Wempty-rule]
+input.y:373.11: warning: empty rule without %empty [-Wempty-rule]
+input.y:387.15: warning: empty rule without %empty [-Wempty-rule]
+input.y:401.18: warning: empty rule without %empty [-Wempty-rule]
+input.y:413.15: warning: empty rule without %empty [-Wempty-rule]
+input.y:443.15: warning: empty rule without %empty [-Wempty-rule]
+input.y:471.15: warning: empty rule without %empty [-Wempty-rule]
+input.y:474.15: warning: empty rule without %empty [-Wempty-rule]
+input.y:489.15: warning: empty rule without %empty [-Wempty-rule]
+input.y:506.14: warning: empty rule without %empty [-Wempty-rule]
+input.y:587.9: warning: empty rule without %empty [-Wempty-rule]
+input.y:591.14: warning: empty rule without %empty [-Wempty-rule]
+]AT_COND_CASE([[canonical LR]],
 [[input.y: warning: 1876 shift/reduce conflicts [-Wconflicts-sr]
-input.y: warning: 144 reduce/reduce conflicts [-Wconflicts-rr]
-input.y:32.9-12: warning: useless associativity for HQUA [-Wother]
-input.y:53.8-14: warning: useless associativity for HASSIGN [-Wother]
-input.y:54.9-15: warning: useless associativity for HORELSE [-Wother]
-input.y:55.9-16: warning: useless associativity for HANDTHEN [-Wother]
-input.y:61.9-12: warning: useless associativity for HNOT [-Wother]
-input.y:68.7-11: warning: useless associativity for UNEAR [-Wother]]],
+input.y: warning: 144 reduce/reduce conflicts [-Wconflicts-rr]]],
 [[input.y: warning: 78 shift/reduce conflicts [-Wconflicts-sr]
-input.y: warning: 10 reduce/reduce conflicts [-Wconflicts-rr]
-input.y:32.9-12: warning: useless associativity for HQUA [-Wother]
-input.y:53.8-14: warning: useless associativity for HASSIGN [-Wother]
-input.y:54.9-15: warning: useless associativity for HORELSE [-Wother]
-input.y:55.9-16: warning: useless associativity for HANDTHEN [-Wother]
-input.y:61.9-12: warning: useless associativity for HNOT [-Wother]
-input.y:68.7-11: warning: useless associativity for UNEAR [-Wother]]])[
+input.y: warning: 10 reduce/reduce conflicts [-Wconflicts-rr]]])[
+input.y:72.1-5: warning: useless associativity for HQUA, use %precedence [-Wprecedence]
+input.y:53.1-6: warning: useless associativity for HASSIGN, use %precedence [-Wprecedence]
+input.y:54.1-5: warning: useless associativity for HORELSE, use %precedence [-Wprecedence]
+input.y:55.1-5: warning: useless associativity for HANDTHEN, use %precedence [-Wprecedence]
+input.y:61.1-5: warning: useless associativity for HNOT, use %precedence [-Wprecedence]
+input.y:68.1-5: warning: useless associativity for UNEAR, use %precedence [-Wprecedence]
 ]],
 
 dnl LAST-STATE
@@ -1585,7 +1593,7 @@ box "foo" above ljust == box ("foo" above ljust)
 
 %left LEFT RIGHT
 /* Give attributes that take an optional expression a higher
-precedence than left and right, so that eg `line chop left'
+precedence than left and right, so that eg 'line chop left'
 parses properly. */
 %left CHOP SOLID DASHED DOTTED UP DOWN FILL COLORED OUTLINED
 %left LABEL
@@ -1598,7 +1606,7 @@ parses properly. */
 /* these need to be lower than '-' */
 %left HEIGHT RADIUS WIDTH DIAMETER FROM TO AT THICKNESS
 
-/* these must have higher precedence than CHOP so that `label %prec CHOP'
+/* these must have higher precedence than CHOP so that 'label %prec CHOP'
 works */
 %left DOT_N DOT_E DOT_W DOT_S DOT_NE DOT_SE DOT_NW DOT_SW DOT_C
 %left DOT_START DOT_END TOP BOTTOM LEFT_CORNER RIGHT_CORNER
@@ -2001,88 +2009,93 @@ dnl without being followed by "of".)
 [[VARIABLE, '=', LABEL, LEFT, DOT_X]],
 
 dnl BISON-STDERR
-[[input.y:471.11-48: warning: rule useless in parser due to conflicts: path: ORDINAL LAST object_type relative_path [-Wother]
-input.y:19.8-12: warning: useless associativity for LABEL [-Wother]
-input.y:20.8-15: warning: useless associativity for VARIABLE [-Wother]
-input.y:21.8-13: warning: useless associativity for NUMBER [-Wother]
-input.y:22.8-11: warning: useless associativity for TEXT [-Wother]
-input.y:25.8-14: warning: useless associativity for ORDINAL [-Wother]
-input.y:30.8-11: warning: useless associativity for LAST [-Wother]
-input.y:31.8-9: warning: useless associativity for UP [-Wother]
-input.y:32.8-11: warning: useless associativity for DOWN [-Wother]
-input.y:35.8-10: warning: useless associativity for BOX [-Wother]
-input.y:36.8-13: warning: useless associativity for CIRCLE [-Wother]
-input.y:37.8-14: warning: useless associativity for ELLIPSE [-Wother]
-input.y:38.8-10: warning: useless associativity for ARC [-Wother]
-input.y:39.8-11: warning: useless associativity for LINE [-Wother]
-input.y:40.8-12: warning: useless associativity for ARROW [-Wother]
-input.y:42.8-13: warning: useless associativity for SPLINE [-Wother]
-input.y:43.8-13: warning: useless associativity for HEIGHT [-Wother]
-input.y:44.8-13: warning: useless associativity for RADIUS [-Wother]
-input.y:45.8-12: warning: useless associativity for WIDTH [-Wother]
-input.y:46.8-15: warning: useless associativity for DIAMETER [-Wother]
-input.y:47.8-11: warning: useless associativity for FROM [-Wother]
-input.y:48.8-9: warning: useless associativity for TO [-Wother]
-input.y:49.8-9: warning: useless associativity for AT [-Wother]
-input.y:53.8-12: warning: useless associativity for SOLID [-Wother]
-input.y:54.8-13: warning: useless associativity for DOTTED [-Wother]
-input.y:55.8-13: warning: useless associativity for DASHED [-Wother]
-input.y:56.8-11: warning: useless associativity for CHOP [-Wother]
-input.y:59.8-12: warning: useless associativity for LJUST [-Wother]
-input.y:60.8-12: warning: useless associativity for RJUST [-Wother]
-input.y:61.8-12: warning: useless associativity for ABOVE [-Wother]
-input.y:62.8-12: warning: useless associativity for BELOW [-Wother]
-input.y:63.8-9: warning: useless associativity for OF [-Wother]
-input.y:66.8-14: warning: useless associativity for BETWEEN [-Wother]
-input.y:67.8-10: warning: useless associativity for AND [-Wother]
-input.y:68.8-11: warning: useless associativity for HERE [-Wother]
-input.y:69.8-12: warning: useless associativity for DOT_N [-Wother]
-input.y:70.8-12: warning: useless associativity for DOT_E [-Wother]
-input.y:71.8-12: warning: useless associativity for DOT_W [-Wother]
-input.y:72.8-12: warning: useless associativity for DOT_S [-Wother]
-input.y:73.8-13: warning: useless associativity for DOT_NE [-Wother]
-input.y:74.8-13: warning: useless associativity for DOT_SE [-Wother]
-input.y:75.8-13: warning: useless associativity for DOT_NW [-Wother]
-input.y:76.8-13: warning: useless associativity for DOT_SW [-Wother]
-input.y:77.8-12: warning: useless associativity for DOT_C [-Wother]
-input.y:78.8-16: warning: useless associativity for DOT_START [-Wother]
-input.y:79.8-14: warning: useless associativity for DOT_END [-Wother]
-input.y:85.8-10: warning: useless associativity for SIN [-Wother]
-input.y:86.8-10: warning: useless associativity for COS [-Wother]
-input.y:87.8-12: warning: useless associativity for ATAN2 [-Wother]
-input.y:88.8-10: warning: useless associativity for LOG [-Wother]
-input.y:89.8-10: warning: useless associativity for EXP [-Wother]
-input.y:90.8-11: warning: useless associativity for SQRT [-Wother]
-input.y:91.8-12: warning: useless associativity for K_MAX [-Wother]
-input.y:92.8-12: warning: useless associativity for K_MIN [-Wother]
-input.y:93.8-10: warning: useless associativity for INT [-Wother]
-input.y:94.8-11: warning: useless associativity for RAND [-Wother]
-input.y:95.8-12: warning: useless associativity for SRAND [-Wother]
-input.y:98.8-10: warning: useless associativity for TOP [-Wother]
-input.y:99.8-13: warning: useless associativity for BOTTOM [-Wother]
-input.y:100.8-12: warning: useless associativity for UPPER [-Wother]
-input.y:101.8-12: warning: useless associativity for LOWER [-Wother]
-input.y:116.8-18: warning: useless associativity for LEFT_CORNER [-Wother]
-input.y:117.8-19: warning: useless associativity for RIGHT_CORNER [-Wother]
-input.y:118.8-12: warning: useless associativity for NORTH [-Wother]
-input.y:119.8-12: warning: useless associativity for SOUTH [-Wother]
-input.y:120.8-11: warning: useless associativity for EAST [-Wother]
-input.y:121.8-11: warning: useless associativity for WEST [-Wother]
-input.y:122.8-13: warning: useless associativity for CENTER [-Wother]
-input.y:123.8-10: warning: useless associativity for END [-Wother]
-input.y:124.8-12: warning: useless associativity for START [-Wother]
-input.y:127.8-11: warning: useless associativity for PLOT [-Wother]
-input.y:128.8-16: warning: useless associativity for THICKNESS [-Wother]
-input.y:129.8-11: warning: useless associativity for FILL [-Wother]
-input.y:130.8-14: warning: useless associativity for COLORED [-Wother]
-input.y:131.8-15: warning: useless associativity for OUTLINED [-Wother]
-input.y:134.8-14: warning: useless associativity for SPRINTF [-Wother]
-input.y:137.7-9: warning: useless associativity for '.' [-Wother]
-input.y:156.23-25: warning: useless associativity for '(' [-Wother]
-input.y:157.20-22: warning: useless associativity for '`' [-Wother]
-input.y:159.48-50: warning: useless associativity for '@<:@' [-Wother]
-input.y:170.7-9: warning: useless associativity for ',' [-Wother]
-input.y:181.8-10: warning: useless associativity for '!' [-Wother]
+[[input.y:202.19: warning: empty rule without %empty [-Wempty-rule]
+input.y:270.6: warning: empty rule without %empty [-Wempty-rule]
+input.y:292.12: warning: empty rule without %empty [-Wempty-rule]
+input.y:309.17: warning: empty rule without %empty [-Wempty-rule]
+input.y:382.13: warning: empty rule without %empty [-Wempty-rule]
+input.y:471.11-48: warning: rule useless in parser due to conflicts [-Wother]
+input.y:154.1-5: warning: useless associativity for LABEL, use %precedence [-Wprecedence]
+input.y:156.1-5: warning: useless associativity for VARIABLE, use %precedence [-Wprecedence]
+input.y:156.1-5: warning: useless associativity for NUMBER, use %precedence [-Wprecedence]
+input.y:141.1-5: warning: useless associativity for TEXT, use %precedence [-Wprecedence]
+input.y:157.1-5: warning: useless associativity for ORDINAL, use %precedence [-Wprecedence]
+input.y:156.1-5: warning: useless associativity for LAST, use %precedence [-Wprecedence]
+input.y:153.1-5: warning: useless associativity for UP, use %precedence [-Wprecedence]
+input.y:153.1-5: warning: useless associativity for DOWN, use %precedence [-Wprecedence]
+input.y:159.1-5: warning: useless associativity for BOX, use %precedence [-Wprecedence]
+input.y:159.1-5: warning: useless associativity for CIRCLE, use %precedence [-Wprecedence]
+input.y:159.1-5: warning: useless associativity for ELLIPSE, use %precedence [-Wprecedence]
+input.y:159.1-5: warning: useless associativity for ARC, use %precedence [-Wprecedence]
+input.y:159.1-5: warning: useless associativity for LINE, use %precedence [-Wprecedence]
+input.y:159.1-5: warning: useless associativity for ARROW, use %precedence [-Wprecedence]
+input.y:159.1-5: warning: useless associativity for SPLINE, use %precedence [-Wprecedence]
+input.y:162.1-5: warning: useless associativity for HEIGHT, use %precedence [-Wprecedence]
+input.y:162.1-5: warning: useless associativity for RADIUS, use %precedence [-Wprecedence]
+input.y:162.1-5: warning: useless associativity for WIDTH, use %precedence [-Wprecedence]
+input.y:162.1-5: warning: useless associativity for DIAMETER, use %precedence [-Wprecedence]
+input.y:162.1-5: warning: useless associativity for FROM, use %precedence [-Wprecedence]
+input.y:162.1-5: warning: useless associativity for TO, use %precedence [-Wprecedence]
+input.y:162.1-5: warning: useless associativity for AT, use %precedence [-Wprecedence]
+input.y:153.1-5: warning: useless precedence and associativity for SOLID [-Wprecedence]
+input.y:153.1-5: warning: useless associativity for DOTTED, use %precedence [-Wprecedence]
+input.y:153.1-5: warning: useless associativity for DASHED, use %precedence [-Wprecedence]
+input.y:153.1-5: warning: useless associativity for CHOP, use %precedence [-Wprecedence]
+input.y:147.1-5: warning: useless precedence and associativity for LJUST [-Wprecedence]
+input.y:147.1-5: warning: useless precedence and associativity for RJUST [-Wprecedence]
+input.y:147.1-5: warning: useless precedence and associativity for ABOVE [-Wprecedence]
+input.y:147.1-5: warning: useless precedence and associativity for BELOW [-Wprecedence]
+input.y:176.1-5: warning: useless associativity for OF, use %precedence [-Wprecedence]
+input.y:176.1-5: warning: useless associativity for BETWEEN, use %precedence [-Wprecedence]
+input.y:177.1-5: warning: useless associativity for AND, use %precedence [-Wprecedence]
+input.y:157.1-5: warning: useless associativity for HERE, use %precedence [-Wprecedence]
+input.y:166.1-5: warning: useless associativity for DOT_N, use %precedence [-Wprecedence]
+input.y:166.1-5: warning: useless associativity for DOT_E, use %precedence [-Wprecedence]
+input.y:166.1-5: warning: useless associativity for DOT_W, use %precedence [-Wprecedence]
+input.y:166.1-5: warning: useless associativity for DOT_S, use %precedence [-Wprecedence]
+input.y:166.1-5: warning: useless associativity for DOT_NE, use %precedence [-Wprecedence]
+input.y:166.1-5: warning: useless associativity for DOT_SE, use %precedence [-Wprecedence]
+input.y:166.1-5: warning: useless associativity for DOT_NW, use %precedence [-Wprecedence]
+input.y:166.1-5: warning: useless associativity for DOT_SW, use %precedence [-Wprecedence]
+input.y:166.1-5: warning: useless associativity for DOT_C, use %precedence [-Wprecedence]
+input.y:167.1-5: warning: useless associativity for DOT_START, use %precedence [-Wprecedence]
+input.y:167.1-5: warning: useless associativity for DOT_END, use %precedence [-Wprecedence]
+input.y:156.1-5: warning: useless associativity for SIN, use %precedence [-Wprecedence]
+input.y:156.1-5: warning: useless associativity for COS, use %precedence [-Wprecedence]
+input.y:156.1-5: warning: useless associativity for ATAN2, use %precedence [-Wprecedence]
+input.y:156.1-5: warning: useless associativity for LOG, use %precedence [-Wprecedence]
+input.y:156.1-5: warning: useless associativity for EXP, use %precedence [-Wprecedence]
+input.y:156.1-5: warning: useless associativity for SQRT, use %precedence [-Wprecedence]
+input.y:156.1-5: warning: useless associativity for K_MAX, use %precedence [-Wprecedence]
+input.y:156.1-5: warning: useless associativity for K_MIN, use %precedence [-Wprecedence]
+input.y:156.1-5: warning: useless associativity for INT, use %precedence [-Wprecedence]
+input.y:156.1-5: warning: useless associativity for RAND, use %precedence [-Wprecedence]
+input.y:156.1-5: warning: useless associativity for SRAND, use %precedence [-Wprecedence]
+input.y:167.1-5: warning: useless associativity for TOP, use %precedence [-Wprecedence]
+input.y:167.1-5: warning: useless associativity for BOTTOM, use %precedence [-Wprecedence]
+input.y:168.1-5: warning: useless associativity for UPPER, use %precedence [-Wprecedence]
+input.y:168.1-5: warning: useless associativity for LOWER, use %precedence [-Wprecedence]
+input.y:167.1-5: warning: useless associativity for LEFT_CORNER, use %precedence [-Wprecedence]
+input.y:167.1-5: warning: useless associativity for RIGHT_CORNER, use %precedence [-Wprecedence]
+input.y:168.1-5: warning: useless associativity for NORTH, use %precedence [-Wprecedence]
+input.y:168.1-5: warning: useless associativity for SOUTH, use %precedence [-Wprecedence]
+input.y:168.1-5: warning: useless associativity for EAST, use %precedence [-Wprecedence]
+input.y:168.1-5: warning: useless associativity for WEST, use %precedence [-Wprecedence]
+input.y:168.1-5: warning: useless associativity for CENTER, use %precedence [-Wprecedence]
+input.y:168.1-5: warning: useless associativity for END, use %precedence [-Wprecedence]
+input.y:168.1-5: warning: useless associativity for START, use %precedence [-Wprecedence]
+input.y:140.1-5: warning: useless associativity for PLOT, use %precedence [-Wprecedence]
+input.y:162.1-5: warning: useless associativity for THICKNESS, use %precedence [-Wprecedence]
+input.y:153.1-5: warning: useless associativity for FILL, use %precedence [-Wprecedence]
+input.y:153.1-5: warning: useless precedence and associativity for COLORED [-Wprecedence]
+input.y:153.1-5: warning: useless precedence and associativity for OUTLINED [-Wprecedence]
+input.y:141.1-5: warning: useless associativity for SPRINTF, use %precedence [-Wprecedence]
+input.y:137.1-5: warning: useless associativity for '.', use %precedence [-Wprecedence]
+input.y:156.1-5: warning: useless associativity for '(', use %precedence [-Wprecedence]
+input.y:157.1-5: warning: useless associativity for '`', use %precedence [-Wprecedence]
+input.y:159.1-5: warning: useless associativity for '@<:@', use %precedence [-Wprecedence]
+input.y:170.1-5: warning: useless associativity for ',', use %precedence [-Wprecedence]
+input.y:181.1-6: warning: useless associativity for '!', use %precedence [-Wprecedence]
 ]],
 
 dnl LAST-STATE

tests/glr-regression.at

@@ -67,7 +67,7 @@ static YYSTYPE exprMerge (YYSTYPE x0, YYSTYPE x1)
   return 0;
 }
 
-const char *input = YY_NULL;
+const char *input = YY_NULLPTR;
 
 int
 main (int argc, const char* argv[])
@@ -304,7 +304,7 @@ MergeRule (int x0, int x1)
 }
 ]AT_YYERROR_DEFINE[
 
-FILE *input = YY_NULL;
+FILE *input = YY_NULLPTR;
 
 int P[] = { P1, P2 };
 int O[] = { O1, O2 };
@@ -486,8 +486,8 @@ start:
    ;
 
 %%
-]AT_YYLEX_DEFINE(["a"])[
 ]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE(["a"])[
 ]AT_MAIN_DEFINE[
 ]])
 AT_BISON_OPTION_POPDEFS
@@ -1015,17 +1015,17 @@ main (void)
   int exit_status = yyparse ();
   if (parent_rhs_before_value)
     {
-      fprintf (stderr, "`parent_rhs_before' destructor not called.\n");
+      fprintf (stderr, "'parent_rhs_before' destructor not called.\n");
       exit_status = 1;
     }
   if (merged_value)
     {
-      fprintf (stderr, "`merged' destructor not called.\n");
+      fprintf (stderr, "'merged' destructor not called.\n");
       exit_status = 1;
     }
   if (parent_rhs_after_value)
     {
-      fprintf (stderr, "`PARENT_RHS_AFTER' destructor not called.\n");
+      fprintf (stderr, "'PARENT_RHS_AFTER' destructor not called.\n");
       exit_status = 1;
     }
   return exit_status;
@@ -1449,7 +1449,7 @@ main (void)
   int exit_status = yyparse () != 1;
   if (parent_rhs_before_value)
     {
-      fprintf (stderr, "`parent_rhs_before' destructor not called.\n");
+      fprintf (stderr, "'parent_rhs_before' destructor not called.\n");
       exit_status = 1;
     }
   return exit_status;
@@ -1679,8 +1679,8 @@ start:
 b: 'b';
 d: /* nada.  */;
 %%
-]AT_YYLEX_DEFINE(["abc"])[
 ]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE(["abc"])[
 ]AT_MAIN_DEFINE[
 ]])
 AT_BISON_OPTION_POPDEFS
@@ -1749,3 +1749,33 @@ Cleanup: popping token 'a' ()
 ])
 
 AT_CLEANUP
+
+
+## ----------------------------------------------------------------- ##
+## Predicates.                                                       ##
+##                                                                   ##
+## http://lists.gnu.org/archive/html/bug-bison/2013-10/msg00004.html ##
+## ----------------------------------------------------------------- ##
+
+AT_SETUP([Predicates])
+
+# FIXME: We need genuine test cases with uses of %?.
+
+AT_DATA_GRAMMAR([input.y],
+[[%glr-parser
+%expect-rr 1
+%%
+// Exercise "%?{...}" and "%? {...}".
+widget:
+  %? {new_syntax} "widget" id new_args  { $$ = f($3, $4); }
+| %?{!new_syntax} "widget" id old_args  { $$ = f($3, $4); }
+;
+id:;
+new_args:;
+old_args:;
+%%
+]])
+
+AT_BISON_CHECK([[input.y]])
+
+AT_CLEANUP

tests/headers.at

@@ -117,9 +117,9 @@ AT_SETUP([Several parsers])
 # nor yy* identifiers in the header.  Check that headers are
 # self-contained, and can be compiled by a C++ compiler.
 m4_pushdef([AT_TEST],
-[AT_BISON_OPTION_PUSHDEFS([%define api.prefix "$1_" $2])
+[AT_BISON_OPTION_PUSHDEFS([%define api.prefix {$1_} $2])
 AT_DATA_GRAMMAR([$1.y],
-[[%define api.prefix "$1_"
+[[%define api.prefix {$1_}
 $2
 %error-verbose
 %union
@@ -223,9 +223,13 @@ AT_CHECK([[$PERL -n -0777 -e '
   s{/\*.*?\*/}{}gs;
   s{//.*}{}g;
   s{\b(YYChar
-      |YYPUSH_MORE(_DEFINED)?
+      |YYPUSH_MORE(?:_DEFINED)?
+      |YYUSE
+      |YY_ATTRIBUTE(?:_PURE|_UNUSED)?
+      |YY_IGNORE_MAYBE_UNINITIALIZED_(?:BEGIN|END)
+      |YY_INITIAL_VALUE
       |YY_\w+_INCLUDED
-      |YY_NULL
+      |YY_NULLPTR
       |(defined|if)\ YYDEBUG
       )\b}{}gx;
   while (/^(.*YY.*)$/gm)