version 3.7.4

* NEWS: Record release date.
c++: shorten the assertions that check whether tokens are correct
2026-08-09 10:45:15 +00:00 · 2020-11-14 12:04:26 +01:00 · 2020-11-13 06:17:52 +01:00 · 2020-11-13 06:17:52 +01:00 · 2020-11-13 06:17:52 +01:00 · 2020-11-13 06:17:52 +01:00
60 changed files with 1245 additions and 524 deletions
@@ -1 +1 @@
-3.6.93
+3.7.3
@@ -50,6 +50,7 @@ jobs:
        - make -j2 dist-xz
        # Can help understanding why we get "dirty" tarballs.
        - git status
+        - git diff
        - dist=$(echo bison*.xz)

        # Unfortunately we cannot deterministically know the name of the tarball without the full
@@ -119,6 +120,8 @@ jobs:
        - CXX='clang++-10 -fsanitize=address -stdlib=libc++'
        - PART=2

+    # See https://github.com/simd-everywhere/simde/blob/master/.travis.yml
+    # and https://software.intel.com/content/www/us/en/develop/documentation/get-started-with-intel-oneapi-render-linux/top/configure-your-system.html.
    - name: "ICC"
      stage: check
      os: linux
@@ -127,7 +130,7 @@ jobs:
        - CC=icc
        - CXX=icpc
      install:
-        - source /opt/intel/inteloneapi/compiler/latest/env/vars.sh
+        - source /opt/intel/oneapi/compiler/latest/env/vars.sh
      addons:
        apt:
          sources:
@@ -1,5 +1,83 @@
 GNU Bison NEWS

+* Noteworthy changes in release 3.7.4 (2020-11-14) [stable]
+
+** Bug fixes
+
+*** Bug fixes in yacc.c
+
+  In Yacc mode, all the tokens are defined twice: once as an enum, and then
+  as a macro.  YYEMPTY was missing its macro.
+
+*** Bug fixes in lalr1.cc
+
+  The lalr1.cc skeleton used to emit internal assertions (using YY_ASSERT)
+  even when the `parse.assert` %define variable is not enabled.  It no
+  longer does.
+
+  The private internal macro YY_ASSERT now obeys the `api.prefix` %define
+  variable.
+
+  When there is a very large number of tokens, some assertions could be long
+  enough to hit arbitrary limits in Visual C++.  They have been rewritten to
+  work around this limitation.
+
+** Changes
+
+  The YYBISON macro in generated "regular C parsers" (from the "yacc.c"
+  skeleton) used to be defined to 1.  It is now defined to the version of
+  Bison as an integer (e.g., 30704 for version 3.7.4).
+
+* Noteworthy changes in release 3.7.3 (2020-10-13) [stable]
+
+** Bug fixes
+
+  Fix concurrent build issues.
+
+  The bison executable is no longer linked uselessly against libreadline.
+
+  Fix incorrect use of yytname in glr.cc.
+
+* Noteworthy changes in release 3.7.2 (2020-09-05) [stable]
+
+  This release of Bison fixes all known bugs reported for Bison in MITRE's
+  Common Vulnerabilities and Exposures (CVE) system.  These vulnerabilities
+  are only about bison-the-program itself, not the generated code.
+
+  Although these bugs are typically irrelevant to how Bison is used, they
+  are worth fixing if only to give users peace of mind.
+
+  There is no known vulnerability in the generated parsers.
+
+** Bug fixes
+
+  Fix concurrent build issues (introduced in Bison 3.5).
+
+  Push parsers always use YYMALLOC/YYFREE (no direct calls to malloc/free).
+
+  Fix portability issues of the test suite, and of bison itself.
+
+  Some unlikely crashes found by fuzzing have been fixed.  This is only
+  about bison itself, not the generated parsers.
+
+
+* Noteworthy changes in release 3.7.1 (2020-08-02) [stable]
+
+** Bug fixes
+
+  Crash when a token alias contains a NUL byte.
+
+  Portability issues with libtextstyle.
+
+  Portability issues of Bison itself with MSVC.
+
+** Changes
+
+  Improvements and fixes in the documentation.
+
+  More precise location about symbol type redefinitions.
+
+
 * Noteworthy changes in release 3.7 (2020-07-23) [stable]

 ** Deprecated features
@@ -537,7 +615,8 @@ GNU Bison NEWS
  \005) with incorrect styling.  Fixes for similar issues with unexpectedly
  short lines (e.g., the file was changed between parsing and diagnosing).

-  Several unlikely crashes found by fuzzing have been fixed.
+  Some unlikely crashes found by fuzzing have been fixed.  This is only
+  about bison itself, not the generated parsers.


 * Noteworthy changes in release 3.5.2 (2020-02-13) [stable]
@@ -27,7 +27,7 @@ Bison from the git repo.  Roughly, run:
 then proceed with the usual `configure && make` steps.

 ## Build from tarball
-See the [INSTALL file](INSTALL] for generic compilation and installation
+See the [INSTALL file](INSTALL) for generic compilation and installation
 instructions.

 Bison requires GNU m4 1.4.6 or later.  See
@@ -42,9 +42,11 @@ installing it.  In that case, do not use `src/bison`: it would use the
 As an experimental feature, diagnostics are now colored, controlled by the
 `--color` and `--style` options.

-To use them, install the libtextstyle library before configuring Bison.  It
-is available from https://alpha.gnu.org/gnu/gettext/, for instance
-https://alpha.gnu.org/pub/gnu/gettext/libtextstyle-0.20.5.tar.gz.
+To use them, install the libtextstyle library, 0.20.5 or newer, before
+configuring Bison.  It is available from https://alpha.gnu.org/gnu/gettext/,
+for instance https://alpha.gnu.org/gnu/gettext/libtextstyle-0.20.5.tar.gz,
+or as part of Gettext 0.21 or newer, for instance
+https://ftp.gnu.org/gnu/gettext/gettext-0.21.tar.gz.

 The option --color supports the following arguments:
 - always, yes: Enable colors.
@@ -61,6 +63,13 @@ To customize the styles, create a CSS file, say `bison-bw.css`, similar to
 then invoke bison with `--style=bison-bw.css`, or set the `BISON_STYLE`
 environment variable to `bison-bw.css`.

+In some diagnostics, bison uses libtextstyle to emit special escapes to
+generate clickable hyperlinks.  The environment variable
+`NO_TERM_HYPERLINKS` can be used to suppress them.  This may be useful for
+terminal emulators which produce garbage output when they receive the escape
+sequence for a hyperlink. Currently (as of 2020), this affects some versions
+of emacs, guake, konsole, lxterminal, rxvt, yakuake.
+
 ## Relocatability
 If you pass `--enable-relocatable` to `configure`, Bison is relocatable.

@@ -106,9 +106,11 @@ Keith Browne              [email protected]
 Ken Moffat                [email protected]
 Kiyoshi Kanazawa          [email protected]
 Lars Maier                [email protected]
+Lars Wendler              [email protected]
 László Várady             [email protected]
 Laurent Mascherpa         [email protected]
 Lie Yan                   [email protected]
+Maarten De Braekeleer     [email protected]
 Magnus Fromreide          [email protected]
 Marc Autret               [email protected]
 Marc Mendiola             [email protected]
@@ -185,6 +187,7 @@ Simon Sobisch             [email protected]
 Stefano Lattarini         [email protected]
 Stephen Cameron           [email protected]
 Steve Murphy              [email protected]
+Suhwan Song               [email protected]
 Sum Wu                    [email protected]
 Théophile Ranquet         [email protected]
 Thiru Ramakrishnan        [email protected]
@@ -1,4 +1,12 @@
-* Bison 3.7
+* Soon
+** gnulib
+Bruno notes:
+
+> I haven't looked deeply, but it strikes me that gnulib/lib/bitset/array.c
+> does not make use of the 'ffsl' function, nor or the 'integer_length_l'
+> function. Maybe because in Bison, all bitsets are so dense that it does
+> not give a performance advantage?
+
 ** Cex
 *** Improve gnulib
 Don't do this (counterexample.c):
@@ -48,13 +56,6 @@ Unless we play it dumb (little structure).

 - promote YYEOF rather than EOF.

-*** D
- is there a way to attach yysymbol_name to the enum itself?  As we did
-  in Java.
-
- It would be better to have TokenKind as return value.  Can we use
-  reflection to support both output types?
-
 ** YYerror
 https://git.savannah.gnu.org/gitweb/?p=gettext.git;a=blob;f=gettext-runtime/intl/plural.y;h=a712255af4f2f739c93336d4ff6556d932a426a5;hb=HEAD

@@ -67,7 +68,7 @@ Stop hard-coding "Calc".  Adjust local.at (look for FIXME).

 ** A dev warning for b4_
 Maybe we should check for m4_ and b4_ leaking out of the m4 processing, as
-Autoconf does.  It would have caught overquotation issues.
+Autoconf does.  It would have caught over-quotation issues.

 ** doc
 I feel it's ugly to use the GNU style to declare functions in the doc.  It
@@ -88,7 +89,7 @@ push parsers on top of pull parser.  Which is currently not relevant, since
 push parsers are measurably slower.

 ** %define parse.error formatted
-How about pushing bistromathics' yyreport_syntax_error as another standard
+How about pushing Bistromathic's yyreport_syntax_error as another standard
 way to generate the error message, and leave to the user the task of
 providing the message formats?  Currently in bistro, it reads:

@@ -202,18 +203,282 @@ The "automaton" and "set" categories are not so useful.  We should probably
 introduce lr(0) and lalr, just the way we have ielr categories.  The
 "closure" function is too verbose, it should probably have its own category.

-"set" can still be used for summariring the important sets.  That would make
+"set" can still be used for summarizing the important sets.  That would make
 tests easy to maintain.

 *** complain.*
 Rename these guys as "diagnostics.*" (or "diagnose.*"), since that's the
-name they have in gcc, clang, etc.  Likewise for the complain_* series of
+name they have in GCC, clang, etc.  Likewise for the complain_* series of
 functions.

 *** ritem
 states/nstates, rules/nrules, ..., ritem/nritems
 Fix the latter.

+* D programming language
+There's a number of features that are missing, here sorted in _suggested_
+order of implementation.
+
+When copying code from other skeletons, keep the comments exactly as they
+are.  Keep the same variable names.  If you change the wording in one place,
+do it in the others too.  In other words: make sure to keep the
+maintenance *simple* by avoiding any gratuitous difference.
+
+** Rename the D example
+Move the current content of examples/d into examples/d/simple.
+
+** Create a second example
+Duplicate examples/d/simple into examples/d/calc.
+
+** Add location tracking to d/calc
+Look at the examples in the other languages to see how to do that.
+
+** yysymbol_name
+The SymbolKind is an enum.  For a given SymbolKind we want to get its string
+representation.  Currently it's a separate table in the parser that does
+that:
+
+  /* Symbol kinds.  */
+  public enum SymbolKind
+  {
+    S_YYEMPTY = -2,  /* No symbol.  */
+    S_YYEOF = 0,                   /* "end of file"  */
+    S_YYerror = 1,                 /* error  */
+    S_YYUNDEF = 2,                 /* "invalid token"  */
+    S_EQ = 3,                      /* "="  */
+    ...
+    S_input = 14,                  /* input  */
+    S_line = 15,                   /* line  */
+    S_exp = 16,                    /* exp  */
+  };
+
+  ...
+
+  /* YYTNAME[SYMBOL-NUM] -- String name of the symbol SYMBOL-NUM.
+     First, the terminals, then, starting at \a yyntokens_, nonterminals.  */
+  private static immutable string[] yytname_ =
+  [
+  "\"end of file\"", "error", "\"invalid token\"", "\"=\"", "\"+\"",
+  "\"-\"", "\"*\"", "\"/\"", "\"(\"", "\")\"", "\"end of line\"",
+  "\"number\"", "UNARY", "$accept", "input", "line", "exp", null
+  ];
+
+  ...
+
+So to get a symbol kind, one runs `yytname_[yykind]`.
+
+Is there a way to attach this conversion to string to SymbolKind?  In Java
+for instance, we have:
+
+  public enum SymbolKind
+  {
+    S_YYEOF(0),                    /* "end of file"  */
+    S_YYerror(1),                  /* error  */
+    S_YYUNDEF(2),                  /* "invalid token"  */
+    ...
+    S_input(16),                   /* input  */
+    S_line(17),                    /* line  */
+    S_exp(18);                     /* exp  */
+
+    private final int yycode_;
+
+    SymbolKind (int n) {
+      this.yycode_ = n;
+    }
+    ...
+    /* YYNAMES_[SYMBOL-NUM] -- String name of the symbol SYMBOL-NUM.
+       First, the terminals, then, starting at \a YYNTOKENS_, nonterminals.  */
+    private static final String[] yynames_ = yynames_init();
+    private static final String[] yynames_init()
+    {
+      return new String[]
+      {
+        i18n("end of file"), i18n("error"), i18n("invalid token"), "!", "+", "-", "*",
+        "/", "^", "(", ")", "=", i18n("end of line"), i18n("number"), "NEG",
+        "$accept", "input", "line", "exp", null
+      };
+    }
+
+    /* The user-facing name of this symbol.  */
+    public final String getName() {
+      return yynames_[yycode_];
+    }
+  };
+
+which allows to write more naturally `yykind.getName()` rather than
+`yytname_[yykind]`.  Is there something comparable in (idiomatic) D?
+
+** Change the return value of yylex
+Historically people were allowed to return any int from the scanner (which
+is convenient and allows `return '+'` from the scanner).  Akim tends to see
+this as an error, we should restrict the return values to TokenKind (not to
+be confused with SymbolKind).
+
+In the case of D, without the history, we have the choice to support or not
+`int`.  If we want to _keep_ `int`, is there a way, say via introspection,
+to support both signatures of yylex?  If we don't keep `int`, just move to
+TokenKind.
+
+** Documentation
+Write documentation about D support in doc/bison.texi.  Imitate the Java
+documentation.  You should be more succinct IMHO.
+
+** Complete Symbols
+The current interface from the scanner to the parser is somewhat clumsy: the
+token kind is returned by yylex, but the value and location are stored in
+the scanner.  This reflects the fact that the implementation of the parser
+uses three variables to deal with each parsed symbol: its kind, its value,
+its location.
+
+So today the scanner of examples/d/calc.d (no locations) looks like:
+
+    if (input.front.isNumber)
+      {
+        import std.conv : parse;
+        semanticVal_.ival = input.parse!int;
+        return TokenKind.NUM;
+      }
+
+and the generated parser:
+
+    /* Read a lookahead token.  */
+    if (yychar == TokenKind.YYEMPTY)
+    {
+      yychar = yylex ();
+      yylval = yylexer.semanticVal;
+    }
+
+The parser class should feature a `Symbol` type which binds together kind,
+value and location, and the scanner should be able to return an instance of
+that type.  Something like
+
+    if (input.front.isNumber)
+      {
+        import std.conv : parse;
+        return parser.Symbol (TokenKind.NUM, input.parse!int);
+      }
+
+** Token Constructors
+In the previous example it is possible to mix incorrectly kinds and values,
+and for instance:
+
+        return parser.Symbol (TokenKind.NUM, "Hello, World!\n");
+
+attaches a string value to NUM kind (wrong, of course).  When
+api.token.constructor is set, in C++, Bison generated "token constructors":
+parser.make_NUM. parser.make_PLUS, parser.make_STRING, etc.  The previous
+example becomes
+
+        return parser.make_NUM ("Hello, World!\n");
+
+which would easily be caught by the type checker.
+
+** Lookahead Correction
+Add support for LAC to the D skeleton.  It should not be too hard: look how
+this is done in lalr1.cc, and mock it.
+
+** Push Parser
+Add support for push parser.  Do not start a nice skeleton, just enhance the
+current one to support push parsers.  This is going to be a tougher nut to
+crack.
+
+First, you need to understand well how the push parser is expected to work.
+To this end:
+- read the doc
+- look at examples/c/pushcalc
+- create an example of a Java push parser.
+- have a look at the generated parser in Java, which has the advantage of
+  being already based on a parser object, instead of just a function.
+
+The C case is harder to read, but it may help too.  Keep in mind that
+because there's no object to maintain state, the C push parser uses some
+struct (yypstate) to preserve this state.  We don't need this in D, the
+parser object will suffice.
+
+I think working directly on the skeleton to add push-parser support is not
+the simplest path.  I suggest that you (1) transform a generated parser into
+a push parser by hand, and then (2) transform lalr1.d to generate such a
+parser.
+
+Use `git commit` frequently to make sure you keep track of your progress.
+
+*** (1.a) Prepare pull parser by hand
+Copy again one of the D examples into say examples/d/pushcalc.  Also
+check-in the generated parser to facilitate experimentation.
+
+- find local variables of yyparse should become members of the parser object
+  (so that we preserve state from one call to the next).
+
+- do it in your generated D parser.  We don't need an equivalent for
+  yypstate, because we already have it: that the parser object itself.
+
+- have your *pull*-parser (i.e., the good old yy::parser::parse()) work
+  properly this way.  Write and run tests.  That's one of the reasons I
+  suggest using examples/d/calc as a starting point: it already has tests,
+  you can/should add more.
+
+At this point you have a pull-parser which you prepared to turn into a
+push-parser.
+
+*** (1.b) Turn pull parser into push parser by hand
+
+- look again at how push parsers are implemented in Java/C to see what needs
+  to change in yyparse so that the control is inverted: parse() will
+  be *given* the tokens, instead of having to call yylex itself.  When I say
+  "look at C", I think your best option are (i) yacc.c (look for b4_push_if)
+  and (ii) examples/c/pushcalc.
+
+- rename parse() as push_parse(Symbol yyla) (or push_parse(TokenKind, Value,
+  Location)) that takes the symbol as argument.  That's the push parser we
+  are looking for.
+
+- define a new parse() function which has the same signature as the usual
+  pull-parser, that repeatedly calls the push_parse function.  Something
+  like this:
+
+int parse ()
+{
+ int status = 0;
+ do {
+  status = this->push_parse (yylex());
+ } while (status == YYPUSH_MORE);
+ return status;
+}
+
+- show me that parser, so that we can validate the approach.
+
+*** (2) Port that into the skeleton
+- once we agree on the API of the push parser, implement it into lalr1.d.
+  You will probaby need help on this regard, but imitation, again, should
+  help.
+
+- have example/d/pushcalc work properly and pass tests
+
+- add tests in the "real" test suite.  Do that in tests/calc.at.  I can
+  help.
+
+- document
+
+** GLR Parser
+This is very ambitious.  That's the final boss.  There are currently no
+"clean" implementation to get inspiration from.
+
+glr.c is very clean but:
+- is low-level C
+- is a different skeleton from yacc.c
+
+glr.cc is (currently) an ugly hack: a C++ shell around glr.c.  Valentin
+Tolmer is currently rewriting glr.cc to be clean C++, but he is not
+finished.  There will be a lot a common code between lalr1.cc and glr.cc, so
+eventually I would like them to be fused into a single skeleton, supporting
+both deterministic and generalized parsing.
+
+It would be great for D to also support this.
+
+The basic ideas of GLR are explained here:
+
+https://www.codeproject.com/Articles/5259825/GLR-Parsing-in-Csharp-How-to-Use-The-Most-Powerful
+
 * Better error messages
 The users are not provided with enough tools to forge their error messages.
 See for instance "Is there an option to change the message produced by
@@ -231,7 +496,7 @@ and older C++ compilers.  Currently the code defaults to defining it to
 define it to the same type as the C ptrdiff_t type.

 * Completion
-Several features are not available in all the backends.
+Several features are not available in all the back-ends.

 - lac: D, Java (easy)
 - push parsers: glr.c, glr.cc, lalr1.cc (not very difficult)
@@ -301,7 +566,7 @@ opposite side we have some use of \l, which is graphviz-specific, in what
 should be generic code.

 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
+print{,-xml} counterpart. We would very much like to re-use the pretty format
 of states from .output for the graphs, etc.

 Since graphviz dies on medium-to-big grammars, maybe consider an other tool?
@@ -579,14 +844,39 @@ to bison. If you're interested, I'll work on a patch.
 Equip the parser with a means to create the (visual) parse tree.


+-----
+
+# LocalWords:  Cex gnulib gl Bistromathic TokenKinds yylex enum YYEOF EOF
+# LocalWords:  YYerror gettext af hb YYERRCODE undef calc FIXME dev yyerror
+# LocalWords:  Autoconf YYUNDEFTOK lexemes parsers Bistromathic's yyreport
+# LocalWords:  const argc yacc yyclearin lookahead destructor Rici incluent
+# LocalWords:  yydestruct yydiscardin catégories d'avertissements sr activé
+# LocalWords:  conflits défaut rr l'alias chaîne n'est attaché un symbole
+# LocalWords:  obsolète règle vide midrule valeurs de intermédiaire ou avec
+# LocalWords:  définies inutilisées priorité associativité inutiles POSIX
+# LocalWords:  incompatibilités tous les autres avertissements sauf dans rp
+# LocalWords:  désactiver CATEGORIE traiter comme des erreurs glr Akim bool
+# LocalWords:  Demaille arith lalr goto struct pathlen nullable ntokens lr
+# LocalWords:  nterm bitsetv ielr ritem nstates nrules nritems yysymbol EQ
+# LocalWords:  SymbolKind YYEMPTY YYUNDEF YYTNAME NUM yyntokens yytname sed
+# LocalWords:  nonterminals yykind yycode YYNAMES yynames init getName conv
+# LocalWords:  TokenKind semanticVal ival yychar yylval yylexer Tolmer hoc
+# LocalWords:  Sobisch YYPTRDIFF ptrdiff Autotest YYPRINT toknum yytoknum
+# LocalWords:  sym Wother stderr FP fixits xgettext fdiagnostics Graphviz
+# LocalWords:  graphviz VCG bitset xml bw maint yytoken YYABORT deps
+# LocalWords:  YYACCEPT yytranslate nonnegative destructors yyerrlab repo
+# LocalWords:  backends stmt expr yy Mardle baz qux Vadim Maslow CPP cpp
+# LocalWords:  yydebug gcc UCHAR EBCDIC gung PDP NUL Pre Florian Krohm utf
+# LocalWords:  YYACT YYLLOC YYLSP yyval yyvsp yylen yyloc yylsp endif
+# LocalWords:  ispell american
+
 Local Variables:
 mode: outline
 coding: utf-8
 fill-column: 76
+ispell-dictionary: "american"
 End:

-----
-
 Copyright (C) 2001-2004, 2006, 2008-2015, 2018-2020 Free Software
 Foundation, Inc.

@@ -45,6 +45,8 @@ gnulib_modules='
  relocatable-prog relocatable-script
  rename
  spawn-pipe stdbool stpcpy stpncpy strdup-posix strerror strverscmp
+  sys_ioctl
+  termios
  timevar
  unicodeio unistd unistd-safer unlink unlocked-io
  update-copyright unsetenv verify
@@ -126,7 +126,7 @@ _sed_rm_comments_q = $(subst ','\'',$(_sed_remove_comments))

 _space_before_paren_exempt =? \\n\\$$
 _space_before_paren_exempt = \
-  (^ *\#|(LA)?LR\([01]\)|percent_(code|define)|b4_syncline|m4_(define|init)|symbol)
+  (^ *\#|(LA)?LR\([01]\)|percent_(code|define)|b4_syncline|m4_(define|init))
 # 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]$$' > /dev/null; then	\
@@ -156,6 +156,7 @@ exclude = \
 $(call exclude,                                                                 \
  bindtextdomain=^lib/main.c$$                                                  \
  cast_of_argument_to_free=^src/muscle-tab.c$$                                  \
+  error_message_uppercase=etc/bench.pl.in$$                                     \
  po_check=^tests|(^po/POTFILES.in|.md)$$                                       \
  preprocessor_indentation=^data/|^lib/|^src/parse-gram.[ch]$$                  \
  program_name=^lib/main.c$$                                                    \
@@ -60,6 +60,9 @@ AC_PROG_CXX
 # Gnulib (early checks).
 gl_EARLY

+# We want ostream_printf and hyperlink support.
+gl_LIBTEXTSTYLE_OPTIONAL([0.20.5])
+
 # Gnulib uses '#pragma GCC diagnostic push' to silence some
 # warnings, but older gcc doesn't support this.
 AC_CACHE_CHECK([whether pragma GCC diagnostic push works],
@@ -49,7 +49,7 @@ m4_define([m4_shift4], [m4_shift(m4_shift(m4_shift(m4_shift($@))))])
 # b4_generated_by
 # ---------------
 m4_define([b4_generated_by],
-[b4_comment([A Bison parser, made by GNU Bison b4_version.])
+[b4_comment([A Bison parser, made by GNU Bison b4_version_string.])
 ])

 # b4_copyright(TITLE, [YEARS])
@@ -633,11 +633,11 @@ m4_define([_b4_type_action],

 ])])

-# b4_type_foreach(MACRO)
-# ----------------------
+# b4_type_foreach(MACRO, [SEP])
+# -----------------------------
 # Invoke MACRO(SYMBOL-NUMS) for each set of SYMBOL-NUMS for each type set.
 m4_define([b4_type_foreach],
-          [m4_map([$1], m4_defn([b4_type_names]))])
+          [m4_map_sep([$1], [$2], m4_defn([b4_type_names]))])



@@ -321,8 +321,9 @@ m4_define([b4_symbol_type_define],
      /// Copy constructor.
      basic_symbol (const basic_symbol& that);]b4_variant_if([[

-      /// Constructor for valueless symbols, and symbols from each type.
-]b4_type_foreach([b4_basic_symbol_constructor_define])], [[
+      /// Constructors for typed symbols.
+]b4_type_foreach([b4_basic_symbol_constructor_define], [
+])], [[
      /// Constructor for valueless symbols.
      basic_symbol (typename Base::kind_type t]b4_locations_if([,
                    YY_MOVE_REF (location_type) l])[);
@@ -58,11 +58,11 @@ m4_define([b4_cpp_guard_close],
 # b4_pull_flag if they use the values of the %define variables api.pure or
 # api.push-pull.
 m4_define([b4_identification],
-[[/* Identify Bison output.  */
-#define YYBISON 1
+[[/* Identify Bison output, and Bison version.  */
+#define YYBISON ]b4_version[

-/* Bison version.  */
-#define YYBISON_VERSION "]b4_version["
+/* Bison version string.  */
+#define YYBISON_VERSION "]b4_version_string["

 /* Skeleton name.  */
 #define YYSKELETON_NAME ]b4_skeleton[]m4_ifdef([b4_pure_flag], [[
@@ -509,10 +509,11 @@ m4_define([b4_token_define],
 # ----------------
 # Output the definition of the tokens.
 m4_define([b4_token_defines],
-[b4_any_token_visible_if([/* Token kinds.  */
-m4_join([
+[[/* Token kinds.  */
+#define ]b4_symbol([-2], [id])[ -2
+]m4_join([
 ], b4_symbol_map([b4_token_define]))
-])])
+])


 # b4_token_enum(TOKEN-NUM)
@@ -103,12 +103,12 @@ m4_define([b4_location_type_if],
 # b4_identification
 # -----------------
 m4_define([b4_identification],
-[/** Version number for the Bison executable that generated this parser.  */
-  public static immutable string yy_bison_version = "b4_version";
+[[/** Version number for the Bison executable that generated this parser.  */
+  public static immutable string yy_bison_version = "]b4_version_string[";

  /** Name of the skeleton that generated this parser.  */
-  public static immutable string yy_bison_skeleton = b4_skeleton;
-])
+  public static immutable string yy_bison_skeleton = ]b4_skeleton[;
+]])


 ## ------------ ##
@@ -172,7 +172,7 @@ m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl
                           const location_type* yylocationp]])[) const
  {
    *yycdebug_ << (yykind < YYNTOKENS ? "token" : "nterm")
-               << ' ' << yytname[yykind] << " ("]b4_locations_if([[
+               << ' ' << yysymbol_name (yykind) << " ("]b4_locations_if([[
               << *yylocationp << ": "]])[;
    yy_symbol_value_print_ (yykind, yyvaluep]b4_locations_if([[, yylocationp]])[);
    *yycdebug_ << ')';
@@ -71,12 +71,12 @@ m4_define([b4_lexer_if],
 # b4_identification
 # -----------------
 m4_define([b4_identification],
-[  /** Version number for the Bison executable that generated this parser.  */
-  public static final String bisonVersion = "b4_version";
+[[  /** Version number for the Bison executable that generated this parser.  */
+  public static final String bisonVersion = "]b4_version_string[";

  /** Name of the skeleton that generated this parser.  */
-  public static final String bisonSkeleton = b4_skeleton;
-])
+  public static final String bisonSkeleton = ]b4_skeleton[;
+]])


 ## ------------ ##
@@ -22,7 +22,7 @@ m4_pushdef([b4_copyright_years],
 # b4_position_file
 # ----------------
 # Name of the file containing the position class, if we want this file.
-b4_defines_if([b4_required_version_if([302], [],
+b4_defines_if([b4_required_version_if([30200], [],
                                      [m4_define([b4_position_file], [position.hh])])])])


@@ -19,7 +19,7 @@
 # b4_stack_file
 # -------------
 # Name of the file containing the stack class, if we want this file.
-b4_defines_if([b4_required_version_if([302], [],
+b4_defines_if([b4_required_version_if([30200], [],
                                      [m4_define([b4_stack_file], [stack.hh])])])


@@ -20,6 +20,13 @@
 ## variant.  ##
 ## --------- ##

+# b4_assert
+# ---------
+# The name of YY_ASSERT.
+m4_define([b4_assert],
+          [b4_api_PREFIX[]_ASSERT])
+
+
 # b4_symbol_variant(YYTYPE, YYVAL, ACTION, [ARGS])
 # ------------------------------------------------
 # Run some ACTION ("build", or "destroy") on YYVAL of symbol type
@@ -71,12 +78,12 @@ m4_map([      b4_symbol_tag_comment], [$@])dnl
 # -------------------
 # The needed includes for variants support.
 m4_define([b4_variant_includes],
-[b4_parse_assert_if([[#include <typeinfo>]])[
-#ifndef YY_ASSERT
+[b4_parse_assert_if([[#include <typeinfo>
+#ifndef ]b4_assert[
 # include <cassert>
-# define YY_ASSERT assert
+# define ]b4_assert[ assert
 #endif
-]])
+]])])



@@ -110,8 +117,8 @@ m4_define([b4_value_type_declare],
    template <typename T>
    semantic_type (YY_RVREF (T) t)]b4_parse_assert_if([
      : yytypeid_ (&typeid (T))])[
-    {
-      YY_ASSERT (sizeof (T) <= size);
+    {]b4_parse_assert_if([[
+      ]b4_assert[ (sizeof (T) <= size);]])[
      new (yyas_<T> ()) T (YY_MOVE (t));
    }

@@ -125,7 +132,7 @@ m4_define([b4_value_type_declare],
    /// Destruction, allowed only if empty.
    ~semantic_type () YY_NOEXCEPT
    {]b4_parse_assert_if([
-      YY_ASSERT (!yytypeid_);
+      ]b4_assert[ (!yytypeid_);
    ])[}

 # if 201103L <= YY_CPLUSPLUS
@@ -133,10 +140,10 @@ m4_define([b4_value_type_declare],
    template <typename T, typename... U>
    T&
    emplace (U&&... u)
-    {]b4_parse_assert_if([
-      YY_ASSERT (!yytypeid_);
-      YY_ASSERT (sizeof (T) <= size);
-      yytypeid_ = & typeid (T);])[
+    {]b4_parse_assert_if([[
+      ]b4_assert[ (!yytypeid_);
+      ]b4_assert[ (sizeof (T) <= size);
+      yytypeid_ = & typeid (T);]])[
      return *new (yyas_<T> ()) T (std::forward <U>(u)...);
    }
 # else
@@ -144,10 +151,10 @@ m4_define([b4_value_type_declare],
    template <typename T>
    T&
    emplace ()
-    {]b4_parse_assert_if([
-      YY_ASSERT (!yytypeid_);
-      YY_ASSERT (sizeof (T) <= size);
-      yytypeid_ = & typeid (T);])[
+    {]b4_parse_assert_if([[
+      ]b4_assert[ (!yytypeid_);
+      ]b4_assert[ (sizeof (T) <= size);
+      yytypeid_ = & typeid (T);]])[
      return *new (yyas_<T> ()) T ();
    }

@@ -155,10 +162,10 @@ m4_define([b4_value_type_declare],
    template <typename T>
    T&
    emplace (const T& t)
-    {]b4_parse_assert_if([
-      YY_ASSERT (!yytypeid_);
-      YY_ASSERT (sizeof (T) <= size);
-      yytypeid_ = & typeid (T);])[
+    {]b4_parse_assert_if([[
+      ]b4_assert[ (!yytypeid_);
+      ]b4_assert[ (sizeof (T) <= size);
+      yytypeid_ = & typeid (T);]])[
      return *new (yyas_<T> ()) T (t);
    }
 # endif
@@ -185,10 +192,10 @@ m4_define([b4_value_type_declare],
    template <typename T>
    T&
    as () YY_NOEXCEPT
-    {]b4_parse_assert_if([
-      YY_ASSERT (yytypeid_);
-      YY_ASSERT (*yytypeid_ == typeid (T));
-      YY_ASSERT (sizeof (T) <= size);])[
+    {]b4_parse_assert_if([[
+      ]b4_assert[ (yytypeid_);
+      ]b4_assert[ (*yytypeid_ == typeid (T));
+      ]b4_assert[ (sizeof (T) <= size);]])[
      return *yyas_<T> ();
    }

@@ -196,10 +203,10 @@ m4_define([b4_value_type_declare],
    template <typename T>
    const T&
    as () const YY_NOEXCEPT
-    {]b4_parse_assert_if([
-      YY_ASSERT (yytypeid_);
-      YY_ASSERT (*yytypeid_ == typeid (T));
-      YY_ASSERT (sizeof (T) <= size);])[
+    {]b4_parse_assert_if([[
+      ]b4_assert[ (yytypeid_);
+      ]b4_assert[ (*yytypeid_ == typeid (T));
+      ]b4_assert[ (sizeof (T) <= size);]])[
      return *yyas_<T> ();
    }

@@ -214,9 +221,9 @@ m4_define([b4_value_type_declare],
    template <typename T>
    void
    swap (self_type& that) YY_NOEXCEPT
-    {]b4_parse_assert_if([
-      YY_ASSERT (yytypeid_);
-      YY_ASSERT (*yytypeid_ == *that.yytypeid_);])[
+    {]b4_parse_assert_if([[
+      ]b4_assert[ (yytypeid_);
+      ]b4_assert[ (*yytypeid_ == *that.yytypeid_);]])[
      std::swap (as<T> (), that.as<T> ());
    }

@@ -388,11 +395,67 @@ m4_define([_b4_token_maker_define],
 ])])


-m4_define([_b4_type_clause],
-[b4_symbol_if([$1], [is_token],
-              [b4_symbol_if([$1], [has_id],
-                            [tok == token::b4_symbol([$1], [id])],
-                            [tok == b4_symbol([$1], [code])])])])
+# b4_token_kind(SYMBOL-NUM)
+# -------------------------
+# Some tokens don't have an ID.
+m4_define([b4_token_kind],
+[b4_symbol_if([$1], [has_id],
+              [token::b4_symbol([$1], [id])],
+              [b4_symbol([$1], [code])])])
+
+
+# _b4_tok_in(SYMBOL-NUM, ...)
+# ---------------------------
+# See b4_tok_in below.  The SYMBOL-NUMs... are tokens only.
+#
+# We iterate over the tokens to group them by "range" of token numbers (not
+# symbols numbers!).
+#
+# b4_fst is the start of that range.
+# b4_prev is the previous value.
+# b4_val is the current value.
+# If b4_val is the successor of b4_prev in token numbers, update the latter,
+#   otherwise emit the code for range b4_fst .. b4_prev.
+# $1 is also used as a terminator in the foreach, but it will not be printed.
+#
+m4_define([_b4_tok_in],
+[m4_pushdef([b4_prev], [$1])dnl
+m4_pushdef([b4_fst], [$1])dnl
+m4_pushdef([b4_sep], [])dnl
+m4_foreach([b4_val], m4_dquote(m4_shift($@, $1)),
+           [m4_if(b4_symbol(b4_val, [code]), m4_eval(b4_symbol(b4_prev, [code]) + 1), [],
+                  [b4_sep[]m4_if(b4_fst, b4_prev,
+                         [tok == b4_token_kind(b4_fst)],
+                         [(b4_token_kind(b4_fst) <= tok && tok <= b4_token_kind(b4_prev))])[]dnl
+m4_define([b4_fst], b4_val)dnl
+m4_define([b4_sep], [
+                   || ])])dnl
+m4_define([b4_prev], b4_val)])dnl
+m4_popdef([b4_sep])dnl
+m4_popdef([b4_fst])dnl
+m4_popdef([b4_prev])dnl
+])
+
+
+# _b4_filter_tokens(SYMBOL-NUM, ...)
+# ----------------------------------
+# Expand as the list of tokens amongst SYMBOL-NUM.
+m4_define([_b4_filter_tokens],
+[m4_pushdef([b4_sep])dnl
+m4_foreach([b4_val], [$@],
+           [b4_symbol_if(b4_val, [is_token], [b4_sep[]b4_val[]m4_define([b4_sep], [,])])])dnl
+m4_popdef([b4_sep])dnl
+])
+
+
+# b4_tok_in(SYMBOL-NUM, ...)
+# ---------------------------
+# A C++ conditional that checks that `tok` is a member of this list of symbol
+# numbers.
+m4_define([b4_tok_in],
+          [_$0(_b4_filter_tokens($@))])
+
+


 # _b4_token_constructor_define(SYMBOL-NUM...)
@@ -410,9 +473,6 @@ m4_define([_b4_token_constructor_define],
        : super_type(]b4_join([token_type (tok)],
                              b4_symbol_if([$1], [has_type], [std::move (v)]),
                              b4_locations_if([std::move (l)]))[)
-      {
-        YY_ASSERT (]m4_join([ || ], m4_map_sep([_b4_type_clause], [, ], [$@]))[);
-      }
 #else
      symbol_type (]b4_join(
          [int tok],
@@ -422,10 +482,10 @@ m4_define([_b4_token_constructor_define],
        : super_type(]b4_join([token_type (tok)],
                              b4_symbol_if([$1], [has_type], [v]),
                              b4_locations_if([l]))[)
-      {
-        YY_ASSERT (]m4_join([ || ], m4_map_sep([_b4_type_clause], [, ], [$@]))[);
-      }
 #endif
+      {]b4_parse_assert_if([[
+        ]b4_assert[ (]b4_tok_in($@)[);
+      ]])[}
 ]])])


@@ -1486,7 +1486,7 @@ yypstate_new (void)
  yypstate *yyps;]b4_pure_if([], [[
  if (yypstate_allocated)
    return YY_NULLPTR;]])[
-  yyps = YY_CAST (yypstate *, malloc (sizeof *yyps));
+  yyps = YY_CAST (yypstate *, YYMALLOC (sizeof *yyps));
  if (!yyps)
    return YY_NULLPTR;]b4_pure_if([], [[
  yypstate_allocated = 1;]])[
@@ -1515,7 +1515,7 @@ yypstate_delete (yypstate *yyps)
 #endif]b4_lac_if([[
      if (yyes != yyesa)
        YYSTACK_FREE (yyes);]])[
-      free (yyps);]b4_pure_if([], [[
+      YYFREE (yyps);]b4_pure_if([], [[
      yypstate_allocated = 0;]])[
    }
 }
@@ -57,44 +57,57 @@
 \gdef\colorPurple{%
 \setcolor{\rgbPurple}%
 }
+\gdef\colorOff{%
+ \setcolor{\maincolor}%
+}

 \gdef\rgbError{0.80 0 0}
-\gdef\colorError{%
+\gdef\diagError{%
 \setcolor{\rgbError}%
 }
 \gdef\rgbNotice{0 0 0.80}
-\gdef\colorNotice{%
+\gdef\diagNotice{%
 \setcolor{\rgbNotice}%
 }
-\gdef\colorOff{%
+\gdef\rgbWarning{0.50 0 0.50}
+\gdef\diagWarning{%
+ \setcolor{\rgbWarning}%
+}
+\gdef\diagOff{%
 \setcolor{\maincolor}%
 }
@end tex

@ifnottex
@macro colorGreen
-@inlineraw{html, <b style="color:green">}
+@inlineraw{html, <span style="color:green">}
@end macro
@macro colorYellow
-@inlineraw{html, <b style="color:#ff8000">}
+@inlineraw{html, <span style="color:#ff8000">}
@end macro
@macro colorRed
-@inlineraw{html, <b style="color:red">}
+@inlineraw{html, <span style="color:red">}
@end macro
@macro colorBlue
-@inlineraw{html, <b style="color:blue">}
+@inlineraw{html, <span style="color:blue">}
@end macro
@macro colorPurple
-@inlineraw{html, <b style="color:darkviolet">}
-@end macro
-
-@macro colorError
-@inlineraw{html, <b style="color:red">}
-@end macro
-@macro colorNotice
-@inlineraw{html, <b style="color:darkcyan">}
+@inlineraw{html, <span style="color:darkviolet">}
@end macro
@macro colorOff
+@inlineraw{html, </span>}
+@end macro
+
+@macro diagError
+@inlineraw{html, <b style="color:red">}
+@end macro
+@macro diagNotice
+@inlineraw{html, <b style="color:darkcyan">}
+@end macro
+@macro diagWarning
+@inlineraw{html, <b style="color:darkviolet">}
+@end macro
+@macro diagOff
@inlineraw{html, </b>}
@end macro
@end ifnottex
@@ -120,15 +133,15 @@
@end macro

@macro dwarning{text}
-@purple{\text\}
+@diagWarning{}\text\@diagOff{}
@end macro

@macro derror{text}
-@colorError{}\text\@colorOff{}
+@diagError{}\text\@diagOff{}
@end macro

@macro dnotice{text}
-@colorNotice{}\text\@colorOff{}
+@diagNotice{}\text\@diagOff{}
@end macro

@finalout
@@ -290,7 +303,7 @@ Grammar Rules for @code{rpcalc}

 * Rpcalc Input::            Explanation of the @code{input} nonterminal
 * Rpcalc Line::             Explanation of the @code{line} nonterminal
-* Rpcalc Expr::             Explanation of the @code{expr} nonterminal
+* Rpcalc Exp::              Explanation of the @code{exp} nonterminal

 Location Tracking Calculator: @code{ltcalc}

@@ -1775,7 +1788,7 @@ rule are referred to as @code{$1}, @code{$2}, and so on.
@menu
 * Rpcalc Input::            Explanation of the @code{input} nonterminal
 * Rpcalc Line::             Explanation of the @code{line} nonterminal
-* Rpcalc Expr::             Explanation of the @code{expr} nonterminal
+* Rpcalc Exp::              Explanation of the @code{exp} nonterminal
@end menu

@node Rpcalc Input
@@ -1840,8 +1853,8 @@ uninitialized (its value will be unpredictable).  This would be a bug if
 that value were ever used, but we don't use it: once rpcalc has printed the
 value of the user's input line, that value is no longer needed.

-@node Rpcalc Expr
-@subsubsection Explanation of @code{expr}
+@node Rpcalc Exp
+@subsubsection Explanation of @code{exp}

 The @code{exp} grouping has several rules, one for each kind of expression.
 The first rule handles the simplest expressions: those that are just
@@ -6283,7 +6296,10 @@ Introduced in Bison 3.3 to replace @code{parser_class_name}.

@item Default Value: @code{YY} for Java, @code{yy} otherwise.

-@item History: introduced in Bison 2.6
+@item History:
+introduced in Bison 2.6, with its argument in double quotes.  Uses braces
+since Bison 3.0 (double quotes are still supported for backward
+compatibility).
@end itemize
@end deffn

@@ -8302,7 +8318,53 @@ write an unambiguous grammar, but that is very hard to do in this case.)
 This particular ambiguity was first encountered in the specifications of
 Algol 60 and is called the ``dangling @code{else}'' ambiguity.

-To avoid warnings from Bison about predictable, legitimate shift/reduce
+To assist the grammar author in understanding the nature of each conflict,
+Bison can be asked to generate ``counterexamples''.  In the present case it
+actually even proves that the grammar is ambiguous by exhibiting a string
+with two different parses:
+
+@macro danglingElseCex
+@group
+@ifnottex
+  Example: @yellow{"if" expr "then"} @blue{"if" expr "then" stmt} @red{•} @blue{"else" stmt}
+  Shift derivation
+    @yellow{if_stmt}
+    @yellow{↳ "if" expr "then"} @green{stmt}
+                        @green{↳} @blue{if_stmt}
+                           @blue{↳ "if" expr "then" stmt} @red{•} @blue{"else" stmt}
+  Example: @yellow{"if" expr "then"} @blue{"if" expr "then" stmt} @red{•} @yellow{"else" stmt}
+  Reduce derivation
+    @yellow{if_stmt}
+    @yellow{↳ "if" expr "then"} @green{stmt}                        @yellow{"else" stmt}
+                        @green{↳} @blue{if_stmt}
+                           @blue{↳ "if" expr "then" stmt} @red{•}
+@end ifnottex
+@iftex
+  Example: @yellow{"if" expr "then"} @blue{"if" expr "then" stmt} @red{•} @blue{"else" stmt}
+  Shift derivation
+    @yellow{if_stmt}
+    @yellow{@arrow{} "if" expr "then"} @green{stmt}
+                        @green{@arrow{}} @blue{if_stmt}
+                           @blue{@arrow{} "if" expr "then" stmt} @red{•} @blue{"else" stmt}
+  Example: @yellow{"if" expr "then"} @blue{"if" expr "then" stmt} @red{•} @yellow{"else" stmt}
+  Reduce derivation
+    @yellow{if_stmt}
+    @yellow{@arrow{} "if" expr "then"} @green{stmt}                        @yellow{"else" stmt}
+                        @green{@arrow{}} @blue{if_stmt}
+                           @blue{@arrow{} "if" expr "then" stmt} @red{•}
+@end iftex
+@end group
+@end macro
+@example
+@danglingElseCex
+@end example
+
+@noindent
+@xref{Counterexamples}, for more details.
+
+@sp 1
+
+To avoid warnings from Bison about predictable, @emph{legitimate} shift/reduce
 conflicts, you can use the @code{%expect @var{n}} declaration.
 There will be no warning as long as the number of shift/reduce conflicts
 is exactly @var{n}, and Bison will report an error if there is a
@@ -8693,7 +8755,8 @@ maybeword:
@end example

@noindent
-The error is an ambiguity: there is more than one way to parse a single
+The error is an ambiguity: as counterexample generation would demonstrate
+(@pxref{Counterexamples}), there is more than one way to parse a single
@code{word} into a @code{sequence}.  It could be reduced to a
@code{maybeword} and then into a @code{sequence} via the second rule.
 Alternatively, nothing-at-all could be reduced into a @code{sequence}
@@ -8890,12 +8953,14 @@ name_list:
 It would seem that this grammar can be parsed with only a single token of
 lookahead: when a @code{param_spec} is being read, an @code{"id"} is a
@code{name} if a comma or colon follows, or a @code{type} if another
-@code{"id"} follows.  In other words, this grammar is LR(1).
+@code{"id"} follows.  In other words, this grammar is LR(1).  Yet Bison
+finds one reduce/reduce conflict, for which counterexample generation
+(@pxref{Counterexamples}) would find a @emph{nonunifying} example.

@cindex LR
@cindex LALR
-However, for historical reasons, Bison cannot by default handle all
-LR(1) grammars.
+This is because Bison does not handle all LR(1) grammars @emph{by default},
+for historical reasons.
 In this grammar, two contexts, that after an @code{"id"} at the beginning
 of a @code{param_spec} and likewise at the beginning of a
@code{return_spec}, are similar enough that Bison assumes they are the
@@ -9870,6 +9935,9 @@ and understand the parser run-time traces (@pxref{Tracing}).

@node Counterexamples
@section Generation of Counterexamples
+@cindex cex
+@cindex counterexamples
+@cindex conflict counterexamples

 Solving conflicts is probably the most delicate part of the design of an LR
 parser, as demonstrated by the number of sections devoted to them in this
@@ -9877,17 +9945,18 @@ very documentation.  To solve a conflict, one must understand it: when does
 it occur?  Is it because of a flaw in the grammar?  Is it rather because
 LR(1) cannot cope with this grammar?

-On difficulty is that conflicts occur in the @emph{automaton}, and it can be
-tricky to related them to issues in the @emph{grammar} itself.  With
-experience and patience, analysis the detailed description of the automaton
-(@pxref{Understanding}) allows to find example strings that reach these conflicts.
+One difficulty is that conflicts occur in the @emph{automaton}, and it can
+be tricky to relate them to issues in the @emph{grammar} itself.  With
+experience and patience, analysis of the detailed description of the
+automaton (@pxref{Understanding}) allows one to find example strings that
+reach these conflicts.

 That task is made much easier thanks to the generation of counterexamples,
 initially developed by Chinawat Isradisaikul and Andrew Myers
@pcite{Isradisaikul 2015}.

-As a first example, see the example grammar of @ref{Shift/Reduce}, which
-features on shift/reduce conflict:
+As a first example, see the grammar of @ref{Shift/Reduce}, which features
+one shift/reduce conflict:

@c see doc/if-then-else.y
@example
@@ -9901,49 +9970,14 @@ Let's rerun @command{bison} with the option
@option{-Wcex}/@option{-Wcounterexamples}@inlinefmt{info, (the following
 output is actually in color)}:

-@ifnottex
@example
 if-then-else.y: @dwarning{warning}: 1 shift/reduce conflict [@dwarning{-Wconflicts-sr}]
 if-then-else.y: @dwarning{warning}: shift/reduce conflict on token "else" [@dwarning{-Wcounterexamples}]
-@group
-  Example: @yellow{"if" expr "then"} "if" expr "then" stmt • "else" stmt
-  Shift derivation
-    @yellow{if_stmt}
-    @yellow{↳ "if" expr "then"} @green{stmt}
-                       @green{↳} @blue{if_stmt}
-                         @blue{↳ "if" expr "then" stmt} @red{•} @blue{"else" stmt}
-  Example: @yellow{"if" expr "then"} @blue{"if" expr "then" stmt} @red{•} @yellow{"else" stmt}
-  Reduce derivation
-    @yellow{if_stmt}
-    @yellow{↳ "if" expr "then"} @green{stmt}                        @yellow{"else" stmt}
-                       @green{↳} @blue{if_stmt}
-                         @blue{↳ "if" expr "then" stmt} @red{•}
-@end group
+@danglingElseCex
@end example
-@end ifnottex
-@iftex
-@example
-if-then-else.y: @dwarning{warning}: 1 shift/reduce conflict [@dwarning{-Wconflicts-sr}]
-if-then-else.y: @dwarning{warning}: shift/reduce conflict on token "else" [@dwarning{-Wcounterexamples}]
-@group
-  Example: @yellow{"if" expr "then"} "if" expr "then" stmt • "else" stmt
-  Shift derivation
-    @yellow{if_stmt}
-    @yellow{@arrow{} "if" expr "then"} @green{stmt}
-                        @green{@arrow{}} @blue{if_stmt}
-                          @blue{@arrow{} "if" expr "then" stmt} @red{•} @blue{"else" stmt}
-  Example: @yellow{"if" expr "then"} @blue{"if" expr "then" stmt} @red{•} @yellow{"else" stmt}
-  Reduce derivation
-    @yellow{if_stmt}
-    @yellow{@arrow{} "if" expr "then"} @green{stmt}                        @yellow{"else" stmt}
-                        @green{@arrow{}} @blue{if_stmt}
-                           @blue{@arrow{} "if" expr "then" stmt} @red{•}
-@end group
-@end example
-@end iftex

-This shows two different derivations for one single expression.  That
-demonstrates that the grammar is ambiguous.
+This shows two different derivations for one single expression, which proves
+that the grammar is ambiguous.

@sp 1

@@ -9966,13 +10000,13 @@ maybeword:

 Bison generates the following counterexamples:

-@ifnottex
@example
@group
 $ @kbd{bison -Wcex sequence.y}
 sequence.y: @dwarning{warning}: 1 shift/reduce conflict [@dwarning{-Wconflicts-sr}]
 sequence.y: @dwarning{warning}: 2 reduce/reduce conflicts [@dwarning{-Wconflicts-rr}]
@end group
+@ifnottex
@group
 sequence.y: @dwarning{warning}: shift/reduce conflict on token "word" [@dwarning{-Wcounterexamples}]
  Example: @red{•} @green{"word"}
@@ -10017,15 +10051,8 @@ sequence.y:8.3-45: @dwarning{warning}: rule useless in parser due to conflicts [
    8 |   @dwarning{%empty    @{ printf ("empty maybeword\n"); @}}
      |   @dwarning{^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~}
@end group
-@end example
@end ifnottex
@iftex
-@example
-@group
-$ @kbd{bison -Wcex sequence.y}
-sequence.y: @dwarning{warning}: 1 shift/reduce conflict [@dwarning{-Wconflicts-sr}]
-sequence.y: @dwarning{warning}: 2 reduce/reduce conflicts [@dwarning{-Wconflicts-rr}]
-@end group
@group
 sequence.y: @dwarning{warning}: shift/reduce conflict on token "word" [@dwarning{-Wcounterexamples}]
  Example: @red{•} @green{"word"}
@@ -10070,12 +10097,12 @@ sequence.y:8.3-45: @dwarning{warning}: rule useless in parser due to conflicts [
    8 |   @dwarning{%empty    @{ printf ("empty maybeword\n"); @}}
      |   @dwarning{^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~}
@end group
-@end example
@end iftex
+@end example

 Each of these three conflicts, again, prove that the grammar is ambiguous.
 For instance, the second conflict (the reduce/reduce one) shows that the
-grammar accept the empty input in two different ways.
+grammar accepts the empty input in two different ways.

@sp 1

@@ -10096,10 +10123,10 @@ expr: %empty | expr ID ','

@command{bison} reports:

-@ifnottex
@example
 ids.y: @dwarning{warning}: 1 shift/reduce conflict [@dwarning{-Wconflicts-sr}]
 ids.y: @dwarning{warning}: shift/reduce conflict on token ID [@dwarning{-Wcounterexamples}]
+@ifnottex
@group
  First example: @purple{expr} @red{•} @purple{ID ','} @green{ID} @yellow{$end}
  Shift derivation
@@ -10120,12 +10147,8 @@ ids.y:4.4-7: @dwarning{warning}: rule useless in parser due to conflicts [@dwarn
    4 | a: expr
      |    ^~~~
@end group
-@end example
@end ifnottex
@iftex
-@example
-ids.y: @dwarning{warning}: 1 shift/reduce conflict [@dwarning{-Wconflicts-sr}]
-ids.y: @dwarning{warning}: shift/reduce conflict on token ID [@dwarning{-Wcounterexamples}]
@group
  First example: @purple{expr} @red{•} @purple{ID ','} @green{ID} @yellow{$end}
  Shift derivation
@@ -10146,8 +10169,8 @@ ids.y:4.4-7: @dwarning{warning}: rule useless in parser due to conflicts [@dwarn
    4 | a: expr
      |    ^~~~
@end group
-@end example
@end iftex
+@end example

 This conflict is caused by the parser not having enough information to know
 the difference between these two examples.  The parser would need an
@@ -15411,6 +15434,12 @@ Macro to discard a value from the parser stack and fake a lookahead
 token.  @xref{Action Features}.
@end deffn

+@deffn {Macro} YYBISON
+The version of Bison as an integer, for instance 30704 for version 3.7.4.
+Defined in @file{yacc.c} only.  Before version 3.7.4, @code{YYBISON} was
+defined to 1.
+@end deffn
+
@deffn {Variable} yychar
 External integer variable that contains the integer value of the
 lookahead token.  (In a pure parser, it is a local variable within
@@ -15631,6 +15660,10 @@ permitted.  @xref{Language and Grammar}.
 A sequence of tokens and/or nonterminals, with one dot, that demonstrates a
 conflict.  The dot marks the place where the conflict occurs.

+@cindex unifying counterexample
+@cindex counterexample, unifying
+@cindex nonunifying counterexample
+@cindex counterexample, nonunifying
 A @emph{unifying} counterexample is a single string that has two different
 parses; its existence proves that the grammar is ambiguous.  When a unifying
 counterexample cannot be found in reasonable time, a @emph{nonunifying}
@@ -57,7 +57,7 @@ MAINTAINERCLEANFILES = $(CROSS_OPTIONS_TEXI)

 # Fix Info's @code in @deftype
 # https://lists.gnu.org/archive/html/help-texinfo/2019-11/msg00004.html
-all: $(srcdir)/$(%C%_bison).info.bak
+all-local: $(srcdir)/$(%C%_bison).info.bak
 $(srcdir)/$(%C%_bison).info.bak: $(srcdir)/$(%C%_bison).info
 	$(AM_V_GEN) $(PERL) -pi.bak -0777	\
 	  -e 's{(^ --.*\n(?: {10}.*\n)*)}'	\
@@ -185,13 +185,13 @@ my $verbose = 1;

 =over 4

-=item C<verbose($level, $message)>
+=item C<verbose ($level, $message)>

 Report the C<$message> is C<$level> E<lt>= C<$verbose>.

 =cut

-sub verbose($$)
+sub verbose ($$)
 {
  my ($level, $message) = @_;
  print STDERR $message
@@ -201,13 +201,13 @@ sub verbose($$)

 ######################################################################

-=item C<directives($bench, @directive)>
+=item C<directives ($bench, @directive)>

 Format the list of directives for Bison for bench named C<$bench>.

 =cut

-sub directives($@)
+sub directives ($@)
 {
  my ($bench, @directive) = @_;
  my $res = "/* Directives for bench '$bench'. */\n";
@@ -218,6 +218,27 @@ sub directives($@)

 ######################################################################

+=item C<is_pure (@directive)>
+
+Whether api.pure is set.
+
+=cut
+
+sub is_pure (@)
+{
+  my (@directive) = @_;
+  for my $dir (@directive)
+    {
+      if ($dir =~ /\A%define api.pure/)
+        {
+          return 1;
+        }
+    }
+  return 0;
+}
+
+######################################################################
+
 =item C<generate_grammar_triangular ($base, $max, @directive)>

 Create a large triangular grammar which looks like :
@@ -389,18 +410,14 @@ sub generate_grammar_calc ($$@)
 %define api.value.type union
 $directives

-%{
+%code provides {
 static int power (int base, int exponent);
 /* yyerror receives the location if:
   - %location & %pure & %glr
   - %location & %pure & %yacc & %parse-param. */
 static void yyerror (const char *s);
-#if YYPURE
-static int yylex (YYSTYPE* yylvalp);
-#else
-static int yylex (void);
-#endif
-%}
+static int yylex (@{[is_pure (@directive) ? "YYSTYPE *yylvalp" : "void"]});
+}

 /* Bison Declarations */
 %token
@@ -467,12 +484,7 @@ yyerror (const char *s)
 }

 static int
-#if YYPURE
-# define yylval (*yylvalp)
-yylex (YYSTYPE* yylvalp)
-#else
-yylex (void)
-#endif
+yylex (@{[is_pure (@directive) ? "YYSTYPE *yylvalp" : "void"]})
 {
  int c;

@@ -498,7 +510,7 @@ yylex (void)
    case '5': case '6': case '7': case '8': case '9':
      {
        int nchars = 0;
-        int n = sscanf (input - 1, "%d%n", &yylval.NUM, &nchars);
+        int n = sscanf (input - 1, "%d%n", &@{[is_pure (@directive) ? "yylvalp->" : "yylval."]}NUM, &nchars);
        assert (n == 1);
        input += nchars - 1;
        return NUM;
@@ -506,7 +518,7 @@ yylex (void)

    default:
      yyerror ("error: invalid character");
-      return yylex ();
+      return yylex (@{[is_pure (@directive) ? "yylvalp" : ""]});
    }
 }
 EOF
@@ -592,10 +604,10 @@ $directives
  // Prototype of the yylex function providing subsequent tokens.
  static
 #if USE_TOKEN_CTOR
-  yy::parser::symbol_type yylex();
+  yy::parser::symbol_type yylex ();
 #else
-  yy::parser::token_type yylex(yy::parser::semantic_type* yylvalp,
-                               yy::parser::location_type* yyllocp);
+  yy::parser::token_type yylex (yy::parser::semantic_type *yylvalp,
+                                yy::parser::location_type *yyllocp);
 #endif

  // Conversion to string.
@@ -618,8 +630,8 @@ EOF
      print $out <<'EOF';
 %token <std::string> TEXT
 %token <int> NUMBER
-%printer { std::cerr << "Number: " << $$; } <int>
-%printer { std::cerr << "Text: " << $$; } <std::string>
+%printer { yyo << "Number: " << $$; } <int>
+%printer { yyo << "Text: " << $$; } <std::string>
 %type <std::string> text result

 %%
@@ -641,8 +653,8 @@ EOF
 %union {int ival; std::string* sval;}
 %token <sval> TEXT
 %token <ival> NUMBER
-%printer { std::cerr << "Number: " << $$; } <ival>
-%printer { std::cerr << "Text: " << *$$; } <sval>
+%printer { yyo << "Number: " << $$; } <ival>
+%printer { yyo << "Text: " << *$$; } <sval>
 %type <sval> text result

 %%
@@ -664,10 +676,10 @@ EOF

 static
 #if USE_TOKEN_CTOR
-yy::parser::symbol_type yylex()
+yy::parser::symbol_type yylex ()
 #else
-yy::parser::token_type yylex(yy::parser::semantic_type* yylvalp,
-                             yy::parser::location_type* yyllocp)
+yy::parser::token_type yylex (yy::parser::semantic_type *yylvalp,
+                              yy::parser::location_type *yyllocp)
 #endif
 {
  typedef yy::parser::location_type location_type;
@@ -251,29 +251,29 @@ err: Next token is token ) (1.4: )
 err: Shifting token ) (1.4: )
 err: Entering state 20
 err: Stack now 0 2 10 20
-err: Reducing stack by rule 15 (line 151):
+err: Reducing stack by rule XX (line XXX):
 err:    $1 = token ( (1.1: )
 err:    $2 = token error (1.2-3: )
 err:    $3 = token ) (1.4: )
 err: -> $$ = nterm exp (1.1-4: 666)
-err: Entering state 7
-err: Stack now 0 7
+err: Entering state 8
+err: Stack now 0 8
 err: Return for a new token:
 err: Reading a token
 err: Now at end of input.
 err: LAC: initial context established for end of file
-err: LAC: checking lookahead end of file: R2 G8 S19
-err: Reducing stack by rule 2 (line 126):
+err: LAC: checking lookahead end of file: R2 G7 S14
+err: Reducing stack by rule XX (line XXX):
 err:    $1 = nterm exp (1.1-4: 666)
 err: -> $$ = nterm input (1.1-4: )
-err: Entering state 8
-err: Stack now 0 8
+err: Entering state 7
+err: Stack now 0 7
 err: Now at end of input.
 err: Shifting token end of file (1.5: )
 err: LAC: initial context discarded due to shift
-err: Entering state 19
-err: Stack now 0 8 19
-err: Stack now 0 8 19
+err: Entering state 14
+err: Stack now 0 7 14
+err: Stack now 0 7 14
 err: Cleanup: popping token end of file (1.5: )
 err: Cleanup: popping nterm input (1.1-4: )' -p

@@ -31,6 +31,13 @@ endif FLEX_WORKS

 %D%/parse.c: $(dependencies)

+# Tell Make scan.o depends on parse.h, except that Make sees only
+# parse.c, not parse.h.  We can't use BUILT_SOURCES to this end, since
+# we use the built bison.
+%D%/lexcalc$(DASH)scan.o: %D%/parse.c
+# Likewise, but for Automake before 1.16.
+%D%/examples_c_lexcalc_lexcalc$(DASH)scan.o: %D%/parse.c
+
 EXTRA_DIST += %D%/lexcalc.test
 dist_lexcalc_DATA = %D%/parse.y %D%/scan.l %D%/Makefile %D%/README.md
 CLEANFILES += %D%/parse.[ch] %D%/scan.c %D%/parse.output
@@ -27,7 +27,7 @@ EXTRA_DIST += %D%/calc.test

 %D%/calc.d: %D%/calc.y $(dependencies)
 	$(AM_V_GEN)$(MKDIR_P) %D%
-	$(AM_V_at)$(BISON) $(srcdir)/%D%/calc.y -o $@
+	$(AM_V_at)$(BISON) -o $@ $(srcdir)/%D%/calc.y

 %D%/calc: %D%/calc.d
 	$(AM_V_GEN) $(DC) $(DCFLAGS) -of$@ %D%/calc.d
@@ -27,7 +27,7 @@ EXTRA_DIST += %D%/Calc.test

 %D%/Calc.java: %D%/Calc.y $(dependencies)
 	$(AM_V_GEN)$(MKDIR_P) %D%
-	$(AM_V_at)$(BISON) $(srcdir)/%D%/Calc.y -o $@
+	$(AM_V_at)$(BISON) -o $@ $(srcdir)/%D%/Calc.y

 %D%/Calc.class: %D%/Calc.java
 	$(AM_V_GEN) $(SHELL) $(top_builddir)/javacomp.sh %D%/Calc.java
@@ -27,7 +27,7 @@ EXTRA_DIST += %D%/Calc.test

 %D%/Calc.java: %D%/Calc.y $(dependencies)
 	$(AM_V_GEN)$(MKDIR_P) %D%
-	$(AM_V_at)$(BISON) $(srcdir)/%D%/Calc.y -o $@
+	$(AM_V_at)$(BISON) -o $@ $(srcdir)/%D%/Calc.y

 %D%/Calc.class: %D%/Calc.java
 	$(AM_V_GEN) $(SHELL) $(top_builddir)/javacomp.sh %D%/Calc.java
@@ -192,8 +192,6 @@
 /localcharset.h
 /locale.h
 /locale.in.h
-/localtime-buffer.c
-/localtime-buffer.h
 /lstat.c
 /malloc.c
 /malloca.c
@@ -338,8 +336,11 @@
 /sys_types.in.h
 /sys_wait.in.h
 /sysexits.in.h
+/termios.h
+/termios.in.h
 /textstyle.h
 /textstyle.in.h
+/thread-optim.h
 /time.h
 /time.in.h
 /timespec.c
@@ -97,7 +97,6 @@
 /locale-ja.m4
 /locale-zh.m4
 /locale_h.m4
-/localtime-buffer.m4
 /lock.m4
 /longlong.m4
 /lstat.m4
@@ -117,6 +116,7 @@
 /msvc-inval.m4
 /msvc-nothrow.m4
 /multiarch.m4
+/musl.m4
 /nls.m4
 /nocrash.m4
 /non-recursive-gnulib-prefix-hack.m4
@@ -128,6 +128,7 @@
 /open.m4
 /pathmax.m4
 /perror.m4
+/pid_t.m4
 /pipe2.m4
 /po.m4
 /posix_spawn.m4
@@ -184,6 +185,7 @@
 /strndup.m4
 /strnlen.m4
 /strverscmp.m4
+/sys_ioctl_h.m4
 /sys_resource_h.m4
 /sys_socket_h.m4
 /sys_stat_h.m4
@@ -191,6 +193,7 @@
 /sys_times_h.m4
 /sys_types_h.m4
 /sys_wait_h.m4
+/termios_h.m4
 /threadlib.m4
 /time_h.m4
 /timespec.m4
@@ -113,13 +113,8 @@ free_counterexample (counterexample *cex)
  free (cex);
 }

-static int max (int a, int b)
-{
-  return a < b ? b : a;
-}
-
 static void
-print_counterexample (const counterexample *cex, FILE *out, const char *prefix)
+counterexample_print (const counterexample *cex, FILE *out, const char *prefix)
 {
  const bool flat = getenv ("YYFLAT");
  const char *example1_label
@@ -131,8 +126,8 @@ print_counterexample (const counterexample *cex, FILE *out, const char *prefix)
  const char *deriv2_label
    = cex->shift_reduce ? _("Reduce derivation") : _("Second reduce derivation");
  const int width =
-    max (max (mbswidth (example1_label, 0), mbswidth (example2_label, 0)),
-         max (mbswidth (deriv1_label, 0),   mbswidth (deriv2_label, 0)));
+    max_int (max_int (mbswidth (example1_label, 0), mbswidth (example2_label, 0)),
+             max_int (mbswidth (deriv1_label, 0),   mbswidth (deriv2_label, 0)));
  if (flat)
    fprintf (out, "  %s%s%*s ", prefix,
             example1_label, width - mbswidth (example1_label, 0), "");
@@ -526,7 +521,7 @@ nonunifying_shift_path (state_item_list reduce_path, state_item *shift_conflict)
      for (gl_list_iterator_t it = gl_list_iterator (result);
           state_item_list_next (&it, &sip);
           )
-        print_state_item (sip, stderr, "");
+        state_item_print (sip, stderr, "");
    }
  return result;
 }
@@ -717,10 +712,10 @@ ssb_equals (const search_state_bundle *s1, const search_state_bundle *s2)
 typedef gl_list_t ssb_list;

 static size_t
-visited_hasher (const search_state *ss, size_t maximum)
+visited_hasher (const search_state *ss, size_t max)
 {
-  return (parse_state_hasher (ss->states[0], maximum)
-          + parse_state_hasher (ss->states[1], maximum)) % maximum;
+  return (parse_state_hasher (ss->states[0], max)
+          + parse_state_hasher (ss->states[1], max)) % max;
 }

 static bool
@@ -1267,7 +1262,7 @@ counterexample_report (state_item_number itm1, state_item_number itm2,
    : example_from_path (shift_reduce, itm2, shortest_path, next_sym);

  gl_list_free (shortest_path);
-  print_counterexample (cex, out, prefix);
+  counterexample_print (cex, out, prefix);
  free_counterexample (cex);
 }

@@ -1290,8 +1285,8 @@ counterexample_report_shift_reduce (state_item_number itm1, state_item_number it
  // In the report, print the items.
  if (out != stderr || trace_flag & trace_cex)
    {
-      print_state_item (&state_items[itm1], out, prefix);
-      print_state_item (&state_items[itm2], out, prefix);
+      state_item_print (&state_items[itm1], out, prefix);
+      state_item_print (&state_items[itm2], out, prefix);
    }
  counterexample_report (itm1, itm2, next_sym, true, out, prefix);
 }
@@ -1334,8 +1329,8 @@ counterexample_report_reduce_reduce (state_item_number itm1, state_item_number i
  // In the report, print the items.
  if (out != stderr || trace_flag & trace_cex)
    {
-      print_state_item (&state_items[itm1], out, prefix);
-      print_state_item (&state_items[itm2], out, prefix);
+      state_item_print (&state_items[itm1], out, prefix);
+      state_item_print (&state_items[itm2], out, prefix);
    }
  counterexample_report (itm1, itm2, bitset_first (conflict_syms),
                         false, out, prefix);
@@ -76,12 +76,12 @@ void derivation_list_free (derivation_list dl)
 derivation *
 derivation_new (symbol_number sym, derivation_list children)
 {
-  derivation *deriv = xmalloc (sizeof (derivation));
-  deriv->sym = sym;
-  deriv->children = children;
-  deriv->reference_count = 0;
-  deriv->color = -1;
-  return deriv;
+  derivation *res = xmalloc (sizeof *res);
+  res->sym = sym;
+  res->children = children;
+  res->reference_count = 0;
+  res->color = -1;
+  return res;
 }

 void
@@ -135,12 +135,6 @@ derivation_size (const derivation *deriv)
 }


-static int
-max (int a, int b)
-{
-  return a < b ? b : a;
-}
-
 // Longest distance from root to leaf.
 static int
 derivation_depth (const derivation *deriv)
@@ -154,7 +148,7 @@ derivation_depth (const derivation *deriv)
      for (gl_list_iterator_t it = gl_list_iterator (deriv->children);
           derivation_list_next (&it, &child);
           )
-        res = max (res, derivation_depth (child));
+        res = max_int (res, derivation_depth (child));
      return res + 1;
    }
  else
@@ -237,7 +231,7 @@ derivation_width (const derivation *deriv)
          // No separator at the beginning.
          children_width -= derivation_separator_width;
        }
-      return max (self_width, children_width);
+      return max_int (self_width, children_width);
    }
  else if (deriv == &d_dot)
    {
@@ -112,7 +112,15 @@ static struct obstack obstack_for_string;
 # define STRING_1GROW(Char)                     \
  obstack_1grow (&obstack_for_string, Char)

-# define STRING_FREE()                                  \
+# ifdef NDEBUG
+#  define STRING_FREE()                                 \
  obstack_free (&obstack_for_string, last_string)
+# else
+#  define STRING_FREE()                                  \
+  do {                                                   \
+    obstack_free (&obstack_for_string, last_string);     \
+    last_string = NULL;                                  \
+  } while (0)
+# endif

 #endif
@@ -423,7 +423,7 @@ ielr_item_has_lookahead (state *s, symbol_number lhs, size_t item,
             check all predecessors' goto follows for the LHS.  */
          if (item_number_is_rule_number (ritem[s->items[item] - 2]))
            {
-              aver (lhs != accept->content->number);
+              aver (lhs != acceptsymbol->content->number);
              for (state **predecessor = predecessors[s->number];
                   *predecessor;
                   ++predecessor)
@@ -103,6 +103,8 @@ src_bison_SOURCES =                             \
  src/state.h                                   \
  src/state-item.c                              \
  src/state-item.h                              \
+  src/strversion.c                              \
+  src/strversion.h                              \
  src/symlist.c                                 \
  src/symlist.h                                 \
  src/symtab.c                                  \
@@ -143,7 +145,6 @@ src_bison_LDADD =                               \
  $(LIB_SETLOCALE_NULL)                         \
  $(LIBICONV)                                   \
  $(LIBINTL)                                    \
-  $(LIBREADLINE)                                \
  $(LIBTEXTSTYLE)


@@ -40,18 +40,6 @@

 location const empty_loc = EMPTY_LOCATION_INIT;

-static int
-min_int (int a, int b)
-{
-  return a < b ? a : b;
-}
-
-static int
-max_int (int a, int b)
-{
-  return a >= b ? a : b;
-}
-
 /* The terminal width.  Not less than 40.  */
 static int
 columns (void)
@@ -167,7 +155,9 @@ int
 location_print (location loc, FILE *out)
 {
  int res = 0;
-  if (trace_flag & trace_locations)
+  if (location_empty (loc))
+    res += fprintf (out, "(empty location)");
+  else if (trace_flag & trace_locations)
    {
      res += boundary_print (&loc.start, out);
      res += fprintf (out, "-");
@@ -256,7 +256,7 @@ shortest_path_from_start (state_item_number target, symbol_number next_sym)
      gl_list_iterator_t it = gl_list_iterator (res);
      const void *sip;
      while (gl_list_iterator_next (&it, &sip, NULL))
-        print_state_item ((state_item *) sip, stdout, "");
+        state_item_print ((state_item *) sip, stdout, "");
    }
  return res;
 }
@@ -127,9 +127,6 @@ muscle_init (void)

  muscle_table = hash_xinitialize (HT_INITIAL_CAPACITY, NULL, hash_muscle,
                                   hash_compare_muscles, muscle_entry_free);
-
-  /* Version and input file.  */
-  MUSCLE_INSERT_STRING ("version", VERSION);
 }


@@ -42,6 +42,7 @@
 #include "scan-skel.h"
 #include "symtab.h"
 #include "tables.h"
+#include "strversion.h"

 static struct obstack format_obstack;

@@ -249,7 +250,7 @@ prepare_symbol_names (char const *muscle_name)
      if (i)
        obstack_1grow (&format_obstack, ' ');
      if (translatable)
-        obstack_sgrow (&format_obstack, "]b4_symbol_translate([");
+        obstack_sgrow (&format_obstack, "]b4_symbol_translate""([");
      obstack_escape (&format_obstack, cp);
      if (translatable)
        obstack_sgrow (&format_obstack, "])[");
@@ -554,7 +555,7 @@ prepare_symbol_definitions (void)
  /* Map "orig NUM" to new numbers.  See data/README.  */
  for (symbol_number i = ntokens; i < nsyms + nuseless_nonterminals; ++i)
    {
-      obstack_printf (&format_obstack, "symbol(orig %d, number)", i);
+      obstack_printf (&format_obstack, "symbol""(orig %d, number)", i);
      const char *key = obstack_finish0 (&format_obstack);
      MUSCLE_INSERT_INT (key, nterm_map ? nterm_map[i - ntokens] : i);
    }
@@ -565,12 +566,12 @@ prepare_symbol_definitions (void)
      const char *key;

 #define SET_KEY(Entry)                                          \
-      obstack_printf (&format_obstack, "symbol(%d, %s)",        \
+      obstack_printf (&format_obstack, "symbol""(%d, %s)",        \
                      i, Entry);                                \
      key = obstack_finish0 (&format_obstack);

 #define SET_KEY2(Entry, Suffix)                                 \
-      obstack_printf (&format_obstack, "symbol(%d, %s_%s)",     \
+      obstack_printf (&format_obstack, "symbol""(%d, %s_%s)",     \
                      i, Entry, Suffix);                        \
      key = obstack_finish0 (&format_obstack);

@@ -807,6 +808,9 @@ prepare (void)
  char const *cp = getenv ("BISON_USE_PUSH_FOR_PULL");
  bool use_push_for_pull_flag = cp && *cp && strtol (cp, 0, 10);

+  /* Versions.  */
+  MUSCLE_INSERT_STRING ("version_string", VERSION);
+  MUSCLE_INSERT_INT ("version", strversion_to_int (VERSION));
  MUSCLE_INSERT_INT ("required_version", required_version);

  /* Flags. */
@@ -1,4 +1,4 @@
-/* A Bison parser, made by GNU Bison 3.6.90.  */
+/* A Bison parser, made by GNU Bison 3.7.3.7-d831b.  */

 /* Bison implementation for Yacc-like parsers in C

@@ -46,10 +46,10 @@
   USER NAME SPACE" below.  */

 /* Identify Bison output.  */
-#define YYBISON 1
+#define YYBISON 30703

 /* Bison version.  */
-#define YYBISON_VERSION "3.6.90"
+#define YYBISON_VERSION "3.7.3.7-d831b"

 /* Skeleton name.  */
 #define YYSKELETON_NAME "yacc.c"
@@ -149,7 +149,7 @@ enum yysymbol_kind_t
  YYSYMBOL_BRACED_CODE = 41,               /* "{...}"  */
  YYSYMBOL_BRACED_PREDICATE = 42,          /* "%?{...}"  */
  YYSYMBOL_BRACKETED_ID = 43,              /* "[identifier]"  */
-  YYSYMBOL_CHAR = 44,                      /* "character literal"  */
+  YYSYMBOL_CHAR_LITERAL = 44,              /* "character literal"  */
  YYSYMBOL_COLON = 45,                     /* ":"  */
  YYSYMBOL_EPILOGUE = 46,                  /* "epilogue"  */
  YYSYMBOL_EQUAL = 47,                     /* "="  */
@@ -162,7 +162,7 @@ enum yysymbol_kind_t
  YYSYMBOL_TAG = 54,                       /* "<tag>"  */
  YYSYMBOL_TAG_ANY = 55,                   /* "<*>"  */
  YYSYMBOL_TAG_NONE = 56,                  /* "<>"  */
-  YYSYMBOL_INT = 57,                       /* "integer literal"  */
+  YYSYMBOL_INT_LITERAL = 57,               /* "integer literal"  */
  YYSYMBOL_PERCENT_PARAM = 58,             /* "%param"  */
  YYSYMBOL_PERCENT_UNION = 59,             /* "%union"  */
  YYSYMBOL_PERCENT_EMPTY = 60,             /* "%empty"  */
@@ -218,8 +218,6 @@ typedef enum yysymbol_kind_t yysymbol_kind_t;
  #include "system.h"

  #include <c-ctype.h>
-  #include <errno.h>
-  #include <intprops.h>
  #include <quotearg.h>
  #include <vasnprintf.h>
  #include <xmemdup0.h>
@@ -233,6 +231,7 @@ typedef enum yysymbol_kind_t yysymbol_kind_t;
  #include "reader.h"
  #include "scan-code.h"
  #include "scan-gram.h"
+  #include "strversion.h"

  /* Pretend to be at least that version, to check features published
     in that version while developping it.  */
@@ -639,19 +638,19 @@ union yyalloc
  /* YYRLINE[YYN] -- Source line where rule number YYN was defined.  */
 static const yytype_int16 yyrline[] =
 {
-       0,   312,   312,   321,   322,   326,   327,   333,   337,   342,
-     343,   344,   345,   346,   347,   348,   353,   358,   359,   360,
-     361,   362,   363,   363,   364,   365,   366,   367,   368,   369,
-     370,   371,   375,   376,   385,   386,   390,   401,   405,   409,
-     417,   427,   428,   438,   439,   445,   458,   458,   463,   463,
-     468,   472,   482,   483,   484,   485,   489,   490,   495,   496,
-     500,   501,   505,   506,   507,   520,   529,   533,   537,   545,
-     546,   550,   563,   564,   569,   570,   571,   589,   593,   597,
-     605,   607,   612,   619,   629,   633,   637,   645,   650,   662,
-     663,   669,   670,   671,   678,   678,   686,   687,   688,   693,
-     696,   698,   700,   702,   704,   706,   708,   710,   712,   717,
-     718,   727,   751,   752,   753,   754,   766,   768,   792,   797,
-     798,   803,   811,   812
+       0,   311,   311,   320,   321,   325,   326,   332,   336,   341,
+     342,   343,   344,   345,   346,   347,   352,   357,   358,   359,
+     360,   361,   362,   362,   363,   364,   365,   366,   367,   368,
+     369,   370,   374,   375,   384,   385,   389,   400,   404,   408,
+     416,   426,   427,   437,   438,   444,   457,   457,   462,   462,
+     467,   471,   481,   482,   483,   484,   488,   489,   494,   495,
+     499,   500,   504,   505,   506,   519,   528,   532,   536,   544,
+     545,   549,   562,   563,   568,   569,   570,   588,   592,   596,
+     604,   606,   611,   618,   628,   632,   636,   644,   649,   661,
+     662,   668,   669,   670,   677,   677,   685,   686,   687,   692,
+     695,   697,   699,   701,   703,   705,   707,   709,   711,   716,
+     717,   726,   750,   751,   752,   753,   765,   767,   791,   796,
+     797,   802,   810,   811
 };
 #endif

@@ -1115,8 +1114,8 @@ tron (yyo);
         { fprintf (yyo, "[%s]", ((*yyvaluep).BRACKETED_ID)); }
        break;

-    case YYSYMBOL_CHAR: /* "character literal"  */
-         { fputs (char_name (((*yyvaluep).CHAR)), yyo); }
+    case YYSYMBOL_CHAR_LITERAL: /* "character literal"  */
+         { fputs (char_name (((*yyvaluep).CHAR_LITERAL)), yyo); }
        break;

    case YYSYMBOL_EPILOGUE: /* "epilogue"  */
@@ -1139,8 +1138,8 @@ tron (yyo);
         { fprintf (yyo, "<%s>", ((*yyvaluep).TAG)); }
        break;

-    case YYSYMBOL_INT: /* "integer literal"  */
-         { fprintf (yyo, "%d", ((*yyvaluep).INT)); }
+    case YYSYMBOL_INT_LITERAL: /* "integer literal"  */
+         { fprintf (yyo, "%d", ((*yyvaluep).INT_LITERAL)); }
        break;

    case YYSYMBOL_PERCENT_PARAM: /* "%param"  */
@@ -2087,11 +2086,11 @@ yyreduce:
    break;

  case 12: /* prologue_declaration: "%expect" "integer literal"  */
-                                   { expected_sr_conflicts = (yyvsp[0].INT); }
+                                   { expected_sr_conflicts = (yyvsp[0].INT_LITERAL); }
    break;

  case 13: /* prologue_declaration: "%expect-rr" "integer literal"  */
-                                   { expected_rr_conflicts = (yyvsp[0].INT); }
+                                   { expected_rr_conflicts = (yyvsp[0].INT_LITERAL); }
    break;

  case 14: /* prologue_declaration: "%file-prefix" "string"  */
@@ -2339,13 +2338,13 @@ yyreduce:

  case 67: /* token_decls: "<tag>" token_decl.1  */
    {
-      (yyval.token_decls) = symbol_list_type_set ((yyvsp[0].yykind_80), (yyvsp[-1].TAG), (yylsp[-1]));
+      (yyval.token_decls) = symbol_list_type_set ((yyvsp[0].yykind_80), (yyvsp[-1].TAG));
    }
    break;

  case 68: /* token_decls: token_decls "<tag>" token_decl.1  */
    {
-      (yyval.token_decls) = symbol_list_append ((yyvsp[-2].token_decls), symbol_list_type_set ((yyvsp[0].yykind_80), (yyvsp[-1].TAG), (yylsp[-1])));
+      (yyval.token_decls) = symbol_list_append ((yyvsp[-2].token_decls), symbol_list_type_set ((yyvsp[0].yykind_80), (yyvsp[-1].TAG)));
    }
    break;

@@ -2396,13 +2395,13 @@ yyreduce:

  case 78: /* token_decls_for_prec: "<tag>" token_decl_for_prec.1  */
    {
-      (yyval.token_decls_for_prec) = symbol_list_type_set ((yyvsp[0].yykind_85), (yyvsp[-1].TAG), (yylsp[-1]));
+      (yyval.token_decls_for_prec) = symbol_list_type_set ((yyvsp[0].yykind_85), (yyvsp[-1].TAG));
    }
    break;

  case 79: /* token_decls_for_prec: token_decls_for_prec "<tag>" token_decl_for_prec.1  */
    {
-      (yyval.token_decls_for_prec) = symbol_list_append ((yyvsp[-2].token_decls_for_prec), symbol_list_type_set ((yyvsp[0].yykind_85), (yyvsp[-1].TAG), (yylsp[-1])));
+      (yyval.token_decls_for_prec) = symbol_list_append ((yyvsp[-2].token_decls_for_prec), symbol_list_type_set ((yyvsp[0].yykind_85), (yyvsp[-1].TAG)));
    }
    break;

@@ -2431,13 +2430,13 @@ yyreduce:

  case 85: /* symbol_decls: "<tag>" symbol_decl.1  */
    {
-      (yyval.symbol_decls) = symbol_list_type_set ((yyvsp[0].yykind_88), (yyvsp[-1].TAG), (yylsp[-1]));
+      (yyval.symbol_decls) = symbol_list_type_set ((yyvsp[0].yykind_88), (yyvsp[-1].TAG));
    }
    break;

  case 86: /* symbol_decls: symbol_decls "<tag>" symbol_decl.1  */
    {
-      (yyval.symbol_decls) = symbol_list_append ((yyvsp[-2].symbol_decls), symbol_list_type_set ((yyvsp[0].yykind_88), (yyvsp[-1].TAG), (yylsp[-1])));
+      (yyval.symbol_decls) = symbol_list_append ((yyvsp[-2].symbol_decls), symbol_list_type_set ((yyvsp[0].yykind_88), (yyvsp[-1].TAG)));
    }
    break;

@@ -2506,7 +2505,7 @@ yyreduce:
    break;

  case 105: /* rhs: rhs "%dprec" "integer literal"  */
-    { grammar_current_rule_dprec_set ((yyvsp[0].INT), (yylsp[0])); }
+    { grammar_current_rule_dprec_set ((yyvsp[0].INT_LITERAL), (yylsp[0])); }
    break;

  case 106: /* rhs: rhs "%merge" "<tag>"  */
@@ -2514,11 +2513,11 @@ yyreduce:
    break;

  case 107: /* rhs: rhs "%expect" "integer literal"  */
-    { grammar_current_rule_expect_sr ((yyvsp[0].INT), (yylsp[0])); }
+    { grammar_current_rule_expect_sr ((yyvsp[0].INT_LITERAL), (yylsp[0])); }
    break;

  case 108: /* rhs: rhs "%expect-rr" "integer literal"  */
-    { grammar_current_rule_expect_rr ((yyvsp[0].INT), (yylsp[0])); }
+    { grammar_current_rule_expect_rr ((yyvsp[0].INT_LITERAL), (yylsp[0])); }
    break;

  case 109: /* named_ref.opt: %empty  */
@@ -2566,9 +2565,9 @@ yyreduce:
          location loc = muscle_percent_define_get_loc (var);
          subcomplain (&loc, complaint, _("definition of %s"), var);
        }
-      (yyval.id) = symbol_get (char_name ((yyvsp[0].CHAR)), (yylsp[0]));
+      (yyval.id) = symbol_get (char_name ((yyvsp[0].CHAR_LITERAL)), (yylsp[0]));
      symbol_class_set ((yyval.id), token_sym, (yylsp[0]), false);
-      symbol_code_set ((yyval.id), (yyvsp[0].CHAR), (yylsp[0]));
+      symbol_code_set ((yyval.id), (yyvsp[0].CHAR_LITERAL), (yylsp[0]));
    }
    break;

@@ -3032,41 +3031,11 @@ handle_pure_parser (location const *loc, char const *directive)
 }


-/* Convert VERSION into an int (MAJOR * 100 + MINOR).  Return -1 on
-   errors.
-
-   Changes of behavior are only on minor version changes, so "3.0.5"
-   is the same as "3.0": 300. */
-static int
-str_to_version (char const *version)
-{
-  IGNORE_TYPE_LIMITS_BEGIN
-  int res = 0;
-  errno = 0;
-  char *cp = NULL;
-  long major = strtol (version, &cp, 10);
-  if (errno || cp == version || *cp != '.' || major < 0
-      || INT_MULTIPLY_WRAPV (major, 100, &res))
-    return -1;
-
-  ++cp;
-  char *cp1 = NULL;
-  long minor = strtol (cp, &cp1, 10);
-  if (errno || cp1 == cp || (*cp1 != '\0' && *cp1 != '.')
-      || ! (0 <= minor && minor < 100)
-      || INT_ADD_WRAPV (minor, res, &res))
-    return -1;
-
-  IGNORE_TYPE_LIMITS_END
-  return res;
-}
-
-
 static void
 handle_require (location const *loc, char const *version_quoted)
 {
  char *version = unquote (version_quoted);
-  required_version = str_to_version (version);
+  required_version = strversion_to_int (version);
  if (required_version == -1)
    {
      complain (loc, complaint, _("invalid version requirement: %s"),
@@ -3147,8 +3116,7 @@ char_name (char c)
    }
 }

-static
-void
+static void
 current_lhs (symbol *sym, location loc, named_ref *ref)
 {
  current_lhs_symbol = sym;
@@ -1,4 +1,4 @@
-/* A Bison parser, made by GNU Bison 3.6.90.  */
+/* A Bison parser, made by GNU Bison 3.7.3.7-d831b.  */

 /* Bison interface for Yacc-like parsers in C

@@ -123,7 +123,7 @@ extern int gram_debug;
    BRACED_CODE = 41,              /* "{...}"  */
    BRACED_PREDICATE = 42,         /* "%?{...}"  */
    BRACKETED_ID = 43,             /* "[identifier]"  */
-    CHAR = 44,                     /* "character literal"  */
+    CHAR_LITERAL = 44,             /* "character literal"  */
    COLON = 45,                    /* ":"  */
    EPILOGUE = 46,                 /* "epilogue"  */
    EQUAL = 47,                    /* "="  */
@@ -136,7 +136,7 @@ extern int gram_debug;
    TAG = 54,                      /* "<tag>"  */
    TAG_ANY = 55,                  /* "<*>"  */
    TAG_NONE = 56,                 /* "<>"  */
-    INT = 57,                      /* "integer literal"  */
+    INT_LITERAL = 57,              /* "integer literal"  */
    PERCENT_PARAM = 58,            /* "%param"  */
    PERCENT_UNION = 59,            /* "%union"  */
    PERCENT_EMPTY = 60             /* "%empty"  */
@@ -156,7 +156,7 @@ union GRAM_STYPE
  char* EPILOGUE;                          /* "epilogue"  */
  char* PROLOGUE;                          /* "%{...%}"  */
  code_props_type code_props_type;         /* code_props_type  */
-  int INT;                                 /* "integer literal"  */
+  int INT_LITERAL;                         /* "integer literal"  */
  int yykind_82;                           /* int.opt  */
  named_ref* yykind_95;                    /* named_ref.opt  */
  param_type PERCENT_PARAM;                /* "%param"  */
@@ -188,7 +188,7 @@ union GRAM_STYPE
  uniqstr yykind_74;                       /* tag.opt  */
  uniqstr tag;                             /* tag  */
  uniqstr variable;                        /* variable  */
-  unsigned char CHAR;                      /* "character literal"  */
+  unsigned char CHAR_LITERAL;              /* "character literal"  */
  value_type value;                        /* value  */


@@ -42,8 +42,6 @@
  #include "system.h"

  #include <c-ctype.h>
-  #include <errno.h>
-  #include <intprops.h>
  #include <quotearg.h>
  #include <vasnprintf.h>
  #include <xmemdup0.h>
@@ -57,6 +55,7 @@
  #include "reader.h"
  #include "scan-code.h"
  #include "scan-gram.h"
+  #include "strversion.h"

  /* Pretend to be at least that version, to check features published
     in that version while developping it.  */
@@ -214,7 +213,7 @@
  BRACED_CODE       "{...}"
  BRACED_PREDICATE  "%?{...}"
  BRACKETED_ID      _("[identifier]")
-  CHAR              _("character literal")
+  CHAR_LITERAL      _("character literal")
  COLON             ":"
  EPILOGUE          _("epilogue")
  EQUAL             "="
@@ -232,7 +231,7 @@
 %code pre-printer  {tron (yyo);}
 %code post-printer {troff (yyo);}

-%type <unsigned char> CHAR
+%type <unsigned char> CHAR_LITERAL
 %printer { fputs (char_name ($$), yyo); } <unsigned char>

 %type <char*> "{...}" "%?{...}" "%{...%}" EPILOGUE STRING TSTRING
@@ -249,7 +248,7 @@
 %printer { fprintf (yyo, "%%%s", $$); } PERCENT_FLAG
 %printer { fprintf (yyo, "<%s>", $$); } TAG tag

-%token <int> INT _("integer literal")
+%token <int> INT_LITERAL _("integer literal")
 %printer { fprintf (yyo, "%d", $$); } <int>

 %type <symbol*> id id_colon string_as_id symbol token_decl token_decl_for_prec
@@ -342,8 +341,8 @@ prologue_declaration:
 | "%defines"                       { defines_flag = true; }
 | "%defines" STRING                { handle_defines ($2); }
 | "%error-verbose"                 { handle_error_verbose (&@$, $1); }
-| "%expect" INT                    { expected_sr_conflicts = $2; }
-| "%expect-rr" INT                 { expected_rr_conflicts = $2; }
+| "%expect" INT_LITERAL            { expected_sr_conflicts = $2; }
+| "%expect-rr" INT_LITERAL         { expected_rr_conflicts = $2; }
 | "%file-prefix" STRING            { handle_file_prefix (&@$, &@1, $1, $2); }
 | "%glr-parser"
    {
@@ -532,11 +531,11 @@ token_decls:
    }
 | TAG token_decl.1[syms]
    {
-      $$ = symbol_list_type_set ($syms, $TAG, @TAG);
+      $$ = symbol_list_type_set ($syms, $TAG);
    }
 | token_decls TAG token_decl.1[syms]
    {
-      $$ = symbol_list_append ($1, symbol_list_type_set ($syms, $TAG, @TAG));
+      $$ = symbol_list_append ($1, symbol_list_type_set ($syms, $TAG));
    }
 ;

@@ -561,7 +560,7 @@ token_decl:
 %type <int> int.opt;
 int.opt:
  %empty  { $$ = -1; }
-| INT
+| INT_LITERAL
 ;

 %type <symbol*> alias;
@@ -592,11 +591,11 @@ token_decls_for_prec:
    }
 | TAG token_decl_for_prec.1[syms]
    {
-      $$ = symbol_list_type_set ($syms, $TAG, @TAG);
+      $$ = symbol_list_type_set ($syms, $TAG);
    }
 | token_decls_for_prec TAG token_decl_for_prec.1[syms]
    {
-      $$ = symbol_list_append ($1, symbol_list_type_set ($syms, $TAG, @TAG));
+      $$ = symbol_list_append ($1, symbol_list_type_set ($syms, $TAG));
    }
 ;

@@ -632,11 +631,11 @@ symbol_decls:
    }
 | TAG symbol_decl.1[syms]
    {
-      $$ = symbol_list_type_set ($syms, $TAG, @TAG);
+      $$ = symbol_list_type_set ($syms, $TAG);
    }
 | symbol_decls TAG symbol_decl.1[syms]
    {
-      $$ = symbol_list_append ($1, symbol_list_type_set ($syms, $TAG, @TAG));
+      $$ = symbol_list_append ($1, symbol_list_type_set ($syms, $TAG));
    }
 ;

@@ -703,13 +702,13 @@ rhs:
    { grammar_current_rule_empty_set (@2); }
 | rhs "%prec" symbol
    { grammar_current_rule_prec_set ($3, @3); }
-| rhs "%dprec" INT
+| rhs "%dprec" INT_LITERAL
    { grammar_current_rule_dprec_set ($3, @3); }
 | rhs "%merge" TAG
    { grammar_current_rule_merge_set ($3, @3); }
-| rhs "%expect" INT
+| rhs "%expect" INT_LITERAL
    { grammar_current_rule_expect_sr ($3, @3); }
-| rhs "%expect-rr" INT
+| rhs "%expect-rr" INT_LITERAL
    { grammar_current_rule_expect_rr ($3, @3); }
 ;

@@ -765,7 +764,7 @@ value:
 id:
  ID
    { $$ = symbol_from_uniqstr ($1, @1); }
-| CHAR
+| CHAR_LITERAL
    {
      const char *var = "api.token.raw";
      if (current_class == nterm_sym)
@@ -1043,41 +1042,11 @@ handle_pure_parser (location const *loc, char const *directive)
 }


-/* Convert VERSION into an int (MAJOR * 100 + MINOR).  Return -1 on
-   errors.
-
-   Changes of behavior are only on minor version changes, so "3.0.5"
-   is the same as "3.0": 300. */
-static int
-str_to_version (char const *version)
-{
-  IGNORE_TYPE_LIMITS_BEGIN
-  int res = 0;
-  errno = 0;
-  char *cp = NULL;
-  long major = strtol (version, &cp, 10);
-  if (errno || cp == version || *cp != '.' || major < 0
-      || INT_MULTIPLY_WRAPV (major, 100, &res))
-    return -1;
-
-  ++cp;
-  char *cp1 = NULL;
-  long minor = strtol (cp, &cp1, 10);
-  if (errno || cp1 == cp || (*cp1 != '\0' && *cp1 != '.')
-      || ! (0 <= minor && minor < 100)
-      || INT_ADD_WRAPV (minor, res, &res))
-    return -1;
-
-  IGNORE_TYPE_LIMITS_END
-  return res;
-}
-
-
 static void
 handle_require (location const *loc, char const *version_quoted)
 {
  char *version = unquote (version_quoted);
-  required_version = str_to_version (version);
+  required_version = strversion_to_int (version);
  if (required_version == -1)
    {
      complain (loc, complaint, _("invalid version requirement: %s"),
@@ -1158,8 +1127,7 @@ char_name (char c)
    }
 }

-static
-void
+static void
 current_lhs (symbol *sym, location loc, named_ref *ref)
 {
  current_lhs_symbol = sym;
@@ -28,19 +28,19 @@
 #include "lssi.h"
 #include "nullable.h"

-typedef struct parse_state
+struct parse_state
 {
-  // path of state-items the parser has traversed
+  // Path of state-items the parser has traversed.
  struct si_chunk
  {
-    // elements newly added in this chunk
+    // Elements newly added in this chunk.
    state_item_list contents;
-    // properties of the linked list this chunk represents
+    // Properties of the linked list this chunk represents.
    const state_item *head_elt;
    const state_item *tail_elt;
    size_t total_size;
  } state_items;
-  // list of derivations of the symbols
+  // List of derivations of the symbols.
  struct deriv_chunk
  {
    derivation_list contents;
@@ -50,18 +50,15 @@ typedef struct parse_state
  } derivs;
  struct parse_state *parent;
  int reference_count;
-  // incremented during productions,
-  // decremented during reductions
+  // Incremented during productions, decremented during reductions.
  int depth;
-  // whether the contents of the chunks should be
-  // prepended or appended to the list the chunks
-  // represent
+  // Whether the contents of the chunks should be prepended or
+  // appended to the list the chunks represent.
  bool prepend;
-  // causes chunk contents to be freed when the
-  // reference count is one. Used when only the chunk metadata
-  // will be needed.
+  // Causes chunk contents to be freed when the reference count is
+  // one. Used when only the chunk metadata will be needed.
  bool free_contents_early;
-} parse_state;
+};


 static void
@@ -438,9 +435,8 @@ simulate_transition (parse_state *ps)
  // symbols into account.
  parse_state_list result = parse_state_list_new ();
  state_item_number si_next = si->trans;
-  // check for disabled transition, shouldn't happen
-  // as any state_items that lead to these should be
-  // disabled.
+  // Check for disabled transition, shouldn't happen as any
+  // state_items that lead to these should be disabled.
  if (si_next < 0)
    return result;
  parse_state *next_ps = copy_parse_state (false, ps);
@@ -594,8 +590,8 @@ print_parse_state (parse_state *ps)
  FILE *out = stderr;
  fprintf (out, "(size %zu depth %d rc %d)\n",
          ps->state_items.total_size, ps->depth, ps->reference_count);
-  print_state_item (ps->state_items.head_elt, out, "");
-  print_state_item (ps->state_items.tail_elt, out, "");
+  state_item_print (ps->state_items.head_elt, out, "");
+  state_item_print (ps->state_items.tail_elt, out, "");
  if (ps->derivs.total_size > 0)
    derivation_print (ps->derivs.head_elt, out, "");
  putc ('\n', out);
@@ -406,8 +406,8 @@ grammar_midrule_action (void)
     action.  Create the MIDRULE.  */
  location dummy_loc = current_rule->action_props.location;
  symbol *dummy = dummy_symbol_get (dummy_loc);
-  symbol_type_set(dummy,
-                  current_rule->action_props.type, current_rule->action_props.location);
+  symbol_type_set (dummy,
+                   current_rule->action_props.type, current_rule->action_props.location);
  symbol_list *midrule = symbol_list_sym_new (dummy, dummy_loc);

  /* Remember named_ref of previous action. */
@@ -804,7 +804,7 @@ check_and_convert_grammar (void)

     $accept: %start $end.  */
  {
-    symbol_list *p = symbol_list_sym_new (accept, empty_loc);
+    symbol_list *p = symbol_list_sym_new (acceptsymbol, empty_loc);
    p->rhs_loc = grammar->rhs_loc;
    p->next = symbol_list_sym_new (startsymbol, empty_loc);
    p->next->next = symbol_list_sym_new (eoftoken, empty_loc);
@@ -815,8 +815,11 @@ check_and_convert_grammar (void)
    grammar = p;
  }

-  aver (nsyms <= SYMBOL_NUMBER_MAXIMUM);
-  aver (nsyms == ntokens + nnterms);
+  if (SYMBOL_NUMBER_MAXIMUM - nnterms < ntokens)
+    complain (NULL, fatal, "too many symbols in input grammar (limit is %d)",
+              SYMBOL_NUMBER_MAXIMUM);
+
+  nsyms = ntokens + nnterms;

  /* Assign the symbols their symbol numbers.  */
  symbols_pack ();
@@ -160,9 +160,9 @@ inaccessable_symbols (void)
  bitset Pp = bitset_create (nrules, BITSET_FIXED);

  /* If the start symbol isn't useful, then nothing will be useful. */
-  if (bitset_test (N, accept->content->number - ntokens))
+  if (bitset_test (N, acceptsymbol->content->number - ntokens))
    {
-      bitset_set (V, accept->content->number);
+      bitset_set (V, acceptsymbol->content->number);

      while (1)
        {
@@ -301,7 +301,7 @@ nonterminals_reduce (void)
      for (item_number *rhsp = rules[r].rhs; 0 <= *rhsp; ++rhsp)
        if (ISVAR (*rhsp))
          *rhsp = symbol_number_as_item_number (nterm_map[*rhsp - ntokens]);
-    accept->content->number = nterm_map[accept->content->number - ntokens];
+    acceptsymbol->content->number = nterm_map[acceptsymbol->content->number - ntokens];
  }

  nsyms -= nuseless_nonterminals;
@@ -381,7 +381,7 @@ reduce_grammar (void)
    {
      reduce_print ();

-      if (!bitset_test (N, accept->content->number - ntokens))
+      if (!bitset_test (N, acceptsymbol->content->number - ntokens))
        complain (&startsymbol_loc, fatal,
                  _("start symbol %s does not derive any sentence"),
                  startsymbol->tag);
@@ -322,8 +322,8 @@ eqopt    ({sp}=)?
    BEGIN SC_AFTER_IDENTIFIER;
  }

-  {int}      RETURN_VALUE (INT, scan_integer (yytext, 10, *loc));
-  {xint}     RETURN_VALUE (INT, scan_integer (yytext, 16, *loc));
+  {int}      RETURN_VALUE (INT_LITERAL, scan_integer (yytext, 10, *loc));
+  {xint}     RETURN_VALUE (INT_LITERAL, scan_integer (yytext, 16, *loc));

  /* Identifiers may not start with a digit.  Yet, don't silently
     accept "1FOO" as "1 FOO".  */
@@ -403,6 +403,7 @@ eqopt    ({sp}=)?
 {
  \0         {
    complain (loc, complaint, _("invalid null character"));
+    STRING_FINISH ();
    STRING_FREE ();
    return GRAM_error;
  }
@@ -566,6 +567,8 @@ eqopt    ({sp}=)?
              _("POSIX Yacc does not support string literals"));
    RETURN_VALUE (STRING, last_string);
  }
+  <<EOF>>   unexpected_eof (token_start, "\"");
+  "\n"      unexpected_newline (token_start, "\"");
 }

 <SC_ESCAPED_TSTRING>
@@ -579,13 +582,10 @@ eqopt    ({sp}=)?
              _("POSIX Yacc does not support string literals"));
    RETURN_VALUE (TSTRING, last_string);
  }
+  <<EOF>>   unexpected_eof (token_start, "\")");
+  "\n"      unexpected_newline (token_start, "\")");
 }

-<SC_ESCAPED_STRING,SC_ESCAPED_TSTRING>
-{
-  <<EOF>>   unexpected_eof (token_start, "\"");
-  "\n"      unexpected_newline (token_start, "\"");
-}


  /*----------------------------------------------------------.
@@ -599,7 +599,6 @@ eqopt    ({sp}=)?
    STRING_FINISH ();
    BEGIN INITIAL;
    loc->start = token_start;
-    val->CHAR = last_string[0];

    if (last_string[0] == '\0')
      {
@@ -615,8 +614,9 @@ eqopt    ({sp}=)?
      }
    else
      {
+        val->CHAR_LITERAL = last_string[0];
        STRING_FREE ();
-        return CHAR;
+        return CHAR_LITERAL;
      }
  }
  {eol}     unexpected_newline (token_start, "'");
@@ -691,6 +691,15 @@ eqopt    ({sp}=)?
              p);
    STRING_1GROW ('?');
  }
+
+  "\\"             {
+    // None of the other rules matched: the last character of this
+    // file is "\".  But Flex does not support "\\<<EOF>>".
+    unexpected_eof (token_start,
+                    YY_START == SC_ESCAPED_CHARACTER ? "?'"
+                    : YY_START == SC_ESCAPED_STRING ? "?\""
+                    : "?\")");
+  }
 }

  /*--------------------------------------------.
@@ -933,9 +942,9 @@ convert_ucn_to_byte (char const *ucn)
 }


-/*---------------------------------------------------------------------.
-| Handle '#line INT( "FILE")?\n'.  ARGS has already skipped '#line '.  |
-`---------------------------------------------------------------------*/
+/*----------------------------------------------------------------------------.
+| Handle '#line INT_LITERAL( "FILE")?\n'.  ARGS has already skipped '#line '. |
+`----------------------------------------------------------------------------*/

 static void
 handle_syncline (char *args, location loc)
@@ -475,7 +475,7 @@ prune_disabled_paths (void)
 }

 void
-print_state_item (const state_item *si, FILE *out, const char *prefix)
+state_item_print (const state_item *si, FILE *out, const char *prefix)
 {
  fputs (prefix, out);
  item_print (si->item, NULL, out);
@@ -506,7 +506,7 @@ state_items_report (void)
          if (si->trans >= 0)
            {
              fputs ("    -> ", stdout);
-              print_state_item (&state_items[si->trans], stdout, "");
+              state_item_print (&state_items[si->trans], stdout, "");
            }

          bitset sets[2] = { si->prods, si->revs };
@@ -521,7 +521,7 @@ state_items_report (void)
                  BITSET_FOR_EACH (biter, b, sin, 0)
                    {
                      fputs (txt[seti], stdout);
-                      print_state_item (&state_items[sin], stdout, "");
+                      state_item_print (&state_items[sin], stdout, "");
                    }
                }
            }
@@ -90,9 +90,10 @@ state_item_index_lookup (state_number s, state_item_number off)
 }

 void state_items_init (void);
-void print_state_item (const state_item *si, FILE *out, const char *prefix);
 void state_items_free (void);

+void state_item_print (const state_item *si, FILE *out, const char *prefix);
+
 bool production_allowed (const state_item *si, const state_item *next);

 // Iterating on a state_item_list.
@@ -0,0 +1,67 @@
+/* Convert version string to int.
+
+   Copyright (C) 2020 Free Software Foundation, Inc.
+
+   This file is part of Bison, the GNU Compiler Compiler.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+#include "system.h"
+
+#include "strversion.h"
+
+#include <errno.h>
+#include <intprops.h>
+
+int
+strversion_to_int (char const *version)
+{
+  IGNORE_TYPE_LIMITS_BEGIN
+  int res = 0;
+  errno = 0;
+  char *cp = NULL;
+
+  {
+    long major = strtol (version, &cp, 10);
+    if (errno || cp == version || *cp != '.' || major < 0
+        || INT_MULTIPLY_WRAPV (major, 10000, &res))
+      return -1;
+  }
+
+  {
+    ++cp;
+    char *prev = cp;
+    long minor = strtol (cp, &cp, 10);
+    if (errno || cp == prev || (*cp != '\0' && *cp != '.')
+        || ! (0 <= minor && minor < 100)
+        || INT_MULTIPLY_WRAPV (minor, 100, &minor)
+        || INT_ADD_WRAPV (minor, res, &res))
+      return -1;
+  }
+
+  if (*cp == '.')
+    {
+      ++cp;
+      char *prev = cp;
+      long micro = strtol (cp, &cp, 10);
+      if (errno || cp == prev || (*cp != '\0' && *cp != '.')
+          || ! (0 <= micro && micro < 100)
+          || INT_ADD_WRAPV (micro, res, &res))
+        return -1;
+    }
+
+  IGNORE_TYPE_LIMITS_END
+  return res;
+}
@@ -0,0 +1,28 @@
+/* Convert version string to int.
+
+   Copyright (C) 2020 Free Software Foundation, Inc.
+
+   This file is part of Bison, the GNU Compiler Compiler.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#ifndef STRVERSION_H_
+# define STRVERSION_H_
+
+/* Convert VERSION into an int (MAJOR * 10000 + MINOR * 100 + MICRO).
+   E.g., "3.7.4" => 30704, "3.8" => 30800.
+   Return -1 on errors. */
+int strversion_to_int (char const *version);
+
+#endif
@@ -83,10 +83,10 @@ symbol_list_type_new (uniqstr type_name, location loc)


 symbol_list *
-symbol_list_type_set (symbol_list *syms, uniqstr type_name, location loc)
+symbol_list_type_set (symbol_list *syms, uniqstr type_name)
 {
  for (symbol_list *l = syms; l; l = l->next)
-    symbol_type_set (l->content.sym, type_name, loc);
+    symbol_type_set (l->content.sym, type_name, l->sym_loc);
  return syms;
 }

@@ -110,8 +110,7 @@ symbol_list *symbol_list_type_new (uniqstr type_name, location loc);

 /** Assign the type \c type_name to all the members of \c syms.
 ** \returns \c syms */
-symbol_list *symbol_list_type_set (symbol_list *syms,
-                                   uniqstr type_name, location loc);
+symbol_list *symbol_list_type_set (symbol_list *syms, uniqstr type_name);

 /** Print this list.

@@ -59,7 +59,7 @@ static semantic_type **semantic_types_sorted = NULL;
 symbol *errtoken = NULL;
 symbol *undeftoken = NULL;
 symbol *eoftoken = NULL;
-symbol *accept = NULL;
+symbol *acceptsymbol = NULL;
 symbol *startsymbol = NULL;
 location startsymbol_loc;

@@ -137,11 +137,6 @@ symbol_new (uniqstr tag, location loc)
  res->alias = NULL;
  res->content = sym_content_new (res);
  res->is_alias = false;
-
-  if (nsyms == SYMBOL_NUMBER_MAXIMUM)
-    complain (NULL, fatal, _("too many symbols in input grammar (limit is %d)"),
-              SYMBOL_NUMBER_MAXIMUM);
-  nsyms++;
  return res;
 }

@@ -182,11 +177,11 @@ symbol_free (void *ptr)
 */

 static void
-symbols_sort (symbol **first, symbol **second)
+symbols_sort (const symbol **first, const symbol **second)
 {
  if (0 < location_cmp ((*first)->location, (*second)->location))
    {
-      symbol* tmp = *first;
+      const symbol* tmp = *first;
      *first = *second;
      *second = tmp;
    }
@@ -243,7 +238,11 @@ semantic_type_new (uniqstr tag, const location *loc)
 | Print a symbol.  |
 `-----------------*/

-#define SYMBOL_ATTR_PRINT(Attr)                         \
+#define SYMBOL_INT_ATTR_PRINT(Attr)                     \
+  if (s->content)                                       \
+    fprintf (f, " %s = %d", #Attr, s->content->Attr)
+
+#define SYMBOL_STR_ATTR_PRINT(Attr)                     \
  if (s->content && s->content->Attr)                   \
    fprintf (f, " %s { %s }", #Attr, s->content->Attr)

@@ -264,7 +263,11 @@ symbol_print (symbol const *s, FILE *f)
               : c == nterm_sym    ? "nterm"
               : NULL, /* abort.  */
               s->tag);
-      SYMBOL_ATTR_PRINT (type_name);
+      putc (' ', f);
+      location_print (s->location, f);
+      SYMBOL_INT_ATTR_PRINT (code);
+      SYMBOL_INT_ATTR_PRINT (number);
+      SYMBOL_STR_ATTR_PRINT (type_name);
      SYMBOL_CODE_PRINT (destructor);
      SYMBOL_CODE_PRINT (printer);
    }
@@ -371,7 +374,7 @@ symbol_from_uniqstr_fuzzy (const uniqstr key)
 }

 static void
-complain_symbol_undeclared (symbol *sym)
+complain_symbol_undeclared (const symbol *sym)
 {
  assert (sym->content->status != declared);
  const symbol *best = symbol_from_uniqstr_fuzzy (sym->tag);
@@ -398,7 +401,10 @@ void
 symbol_location_as_lhs_set (symbol *sym, location loc)
 {
  if (!sym->location_of_lhs)
-    sym->location = loc;
+    {
+      sym->location = loc;
+      sym->location_of_lhs = true;
+    }
 }


@@ -548,10 +554,6 @@ symbol_class_set (symbol *sym, symbol_class class, location loc, bool declaring)
      if (class == token_sym && s->class == pct_type_sym)
        complain_pct_type_on_token (&sym->location);

-      if (class == nterm_sym && s->class != nterm_sym)
-        s->number = nnterms++;
-      else if (class == token_sym && s->number == NUMBER_UNDEFINED)
-        s->number = ntokens++;
      s->class = class;

      if (declaring)
@@ -573,9 +575,9 @@ symbol_class_set (symbol *sym, symbol_class class, location loc, bool declaring)
 }


-/*------------------------------------------------.
-| Set the USER_TOKEN_NUMBER associated with SYM.  |
-`------------------------------------------------*/
+/*----------------------------.
+| Set the token code of SYM.  |
+`----------------------------*/

 void
 symbol_code_set (symbol *sym, int code, location loc)
@@ -598,10 +600,6 @@ symbol_code_set (symbol *sym, int code, location loc)
      if (code == 0 && !eoftoken)
        {
          eoftoken = sym->content->symbol;
-          /* It is always mapped to 0, so it was already counted in
-             NTOKENS.  */
-          if (eoftoken->content->number != NUMBER_UNDEFINED)
-            --ntokens;
          eoftoken->content->number = 0;
        }
    }
@@ -621,9 +619,11 @@ symbol_check_defined (symbol *sym)
    {
      complain_symbol_undeclared (sym);
      s->class = nterm_sym;
-      s->number = nnterms++;
    }

+  if (s->number == NUMBER_UNDEFINED)
+    s->number = s->class == token_sym ? ntokens++ : nnterms++;
+
  if (s->class == token_sym
      && sym->tag[0] == '"'
      && !sym->is_alias)
@@ -742,7 +742,7 @@ symbol_pack (symbol *sym)
 }

 static void
-complain_code_redeclared (int num, symbol *first, symbol *second)
+complain_code_redeclared (int num, const symbol *first, const symbol *second)
 {
  symbols_sort (&first, &second);
  complain (&second->location, complaint,
@@ -758,13 +758,11 @@ complain_code_redeclared (int num, symbol *first, symbol *second)
 `-------------------------------------------------*/

 static void
-symbol_translation (symbol *sym)
+symbol_translation (const symbol *sym)
 {
-  /* Nonterminal? */
-  if (sym->content->class == token_sym
-      && !sym->is_alias)
+  if (sym->content->class == token_sym && !sym->is_alias)
    {
-      /* A token which translation has already been set?*/
+      /* A token whose translation has already been set? */
      if (token_translations[sym->content->code]
          != undeftoken->content->number)
        complain_code_redeclared
@@ -849,10 +847,10 @@ symbols_new (void)
                                   hash_symbol_comparator,
                                   symbol_free);

-  /* Construct the accept symbol. */
-  accept = symbol_get ("$accept", empty_loc);
-  accept->content->class = nterm_sym;
-  accept->content->number = nnterms++;
+  /* Construct the acceptsymbol symbol. */
+  acceptsymbol = symbol_get ("$accept", empty_loc);
+  acceptsymbol->content->class = nterm_sym;
+  acceptsymbol->content->number = nnterms++;

  /* Construct the YYerror/"error" token */
  errtoken = symbol_get ("YYerror", empty_loc);
@@ -969,7 +967,6 @@ dummy_symbol_get (location loc)
  assure (len < sizeof buf);
  symbol *sym = symbol_get (buf, loc);
  sym->content->class = nterm_sym;
-  sym->content->number = nnterms++;
  return sym;
 }

@@ -1002,7 +999,7 @@ symbol_cmp (void const *a, void const *b)
 }

 /* Store in *SORTED an array of pointers to the symbols contained in
-   TABLE, sorted (alphabetically) by tag. */
+   TABLE, sorted by order of appearance (i.e., by location). */

 static void
 table_sort (struct hash_table *table, symbol ***sorted)
@@ -227,7 +227,7 @@ void symbol_precedence_set (symbol *sym, int prec, assoc a, location loc);
 void symbol_class_set (symbol *sym, symbol_class class, location loc,
                       bool declaring);

-/** Set the \c code associated with \c sym.  */
+/** Set the token \c code of \c sym, specified by the user at \c loc.  */
 void symbol_code_set (symbol *sym, int code, location loc);


@@ -245,7 +245,7 @@ extern symbol *eoftoken;
 /** The genuine start symbol.

   $accept: start-symbol $end */
-extern symbol *accept;
+extern symbol *acceptsymbol;

 /** The user start symbol. */
 extern symbol *startsymbol;
@@ -131,6 +131,22 @@ typedef size_t uintptr_t;
 # include <stdbool.h>


+/*-----------.
+| Integers.  |
+`-----------*/
+
+static inline int
+min_int (int a, int b)
+{
+  return a < b ? a : b;
+}
+
+static inline int
+max_int (int a, int b)
+{
+  return a >= b ? a : b;
+}
+

 /*-------------.
 | Assertions.  |
@@ -915,6 +915,12 @@ AT_BISON_OPTION_PUSHDEFS([$1])

 AT_DATA_CALC_Y([$1])
 AT_FULL_COMPILE(AT_JAVA_IF([[Calc]], [[calc]]), AT_DEFINES_IF([[lex], [main]], [[], []]), [$2], [-Wno-deprecated])
+
+AT_YACC_IF(
+  [# No direct calls to malloc/free.
+  AT_CHECK([[$EGREP '(malloc|free) *\(' calc.[ch] | $EGREP -v 'INFRINGES ON USER NAME SPACE']],
+           [1])])
+
 AT_PUSH_IF([AT_JAVA_IF(
 [# Verify that this is a push parser.
  AT_CHECK_JAVA_GREP([[Calc.java]],
@@ -204,17 +204,20 @@ AT_SETUP([Several parsers])
 # Generate and compile to *.o.  Make sure there is no (allowed) YY*
 # nor yy* identifiers in the header after applying api.prefix.  Check
 # that headers can be compiled by a C++ compiler.
+#
+# They should all use parse.assert to make sure that we don't even
+# conflict of YY_ASSERT.
 m4_pushdef([AT_TEST],
-[AT_BISON_OPTION_PUSHDEFS([%define api.prefix {$1_} $2])
+[AT_BISON_OPTION_PUSHDEFS([%define api.prefix {$1_} %define parse.assert $2])
 AT_DATA_GRAMMAR([$1.y],
 [[%define api.prefix {$1_}
+%define parse.assert
 $2
 %define parse.error verbose
-%union
-{
-  int integer;
-}
-%{
+]AT_VARIANT_IF([],
+[%union {int integer;}])[
+
+%code {
 #include <stdio.h> /* printf. */
 ]AT_PUSH_IF([[
 #if defined __GNUC__ && (7 == __GNUC__ || 9 == __GNUC__)
@@ -223,8 +226,10 @@ $2
 ]])[
  ]AT_YYERROR_DECLARE[
  ]AT_YYLEX_DECLARE[
-%}
+}
+
 %%
+
 exp:
  'x' '1' { printf ("x1\n"); }
 | 'x' '2' { printf ("x2\n"); }
@@ -235,9 +240,12 @@ exp:
 | 'x' '7' { printf ("x7\n"); }
 | 'x' '8' { printf ("x8\n"); }
 | 'x' '9' { printf ("x9\n"); }
+| 'x' 'a' { printf ("xa\n"); }
+| 'x' 'b' { printf ("xb\n"); }
 ;

 %%
+
 ]AT_YYERROR_DEFINE[
 ]AT_YYLEX_DEFINE(["$1"])[
 ]])
@@ -270,6 +278,8 @@ extern "C"
 #endif
 #include "x5.hh"
 #include "x9.hh"
+#include "xa.hh"
+#include "xb.hh"

 #define RUN(S)                                  \
  do {                                          \
@@ -292,6 +302,10 @@ main (void)
  RUN(x8_parse());
  x9_::parser p9;
  RUN(p9.parse());
+  xa_::parser pa;
+  RUN(pa.parse());
+  xb_::parser pb;
+  RUN(pb.parse());
  return 0;
 }
 ]])# main.cc
@@ -304,7 +318,9 @@ AT_TEST([x5], [%locations %debug %language "c++"])
 AT_TEST([x6], [%define api.pure])
 AT_TEST([x7], [%define api.push-pull both])
 AT_TEST([x8], [%define api.pure %define api.push-pull both])
-AT_TEST([x9], [%locations %code requires {#include "location.hh"} %define api.location.type {x5_::location} %debug %language "c++"])
+AT_TEST([x9], [%locations %code requires {#include "location.hh"} %define api.location.type {::x5_::location} %debug %language "c++"])
+AT_TEST([xa], [%locations %code requires {#include "location.hh"} %define api.location.type {::x5_::location} %language "c++" %define api.value.type variant])
+AT_TEST([xb], [%locations %define api.location.file none %language "c++" %define api.value.type variant])
 #AT_TEST([x5], [%locations %language "c++" %glr-parser])

 # Check that api.prefix works properly:
@@ -340,6 +356,8 @@ AT_PERL_CHECK([[-n -0777 -e '
      |YY_NULLPTR
      |YY_RVREF
      |YY_\w+_INCLUDED
+      |FILE\ \*yyo   # Function argument.
+      |const\ yylocp # Function argument.
      )\b}{}gx;
  while (/^(.*YY.*)$/gm)
  {
@@ -357,7 +375,7 @@ AT_PERL_CHECK([[-n -0777 -e '
 # Do this late, so that other checks have been performed.
 AT_SKIP_IF_CANNOT_LINK_C_AND_CXX

-AT_COMPILE_CXX([parser], [[x[1-9].o -DCC_IS_CXX=$CC_IS_CXX main.cc]])
+AT_COMPILE_CXX([parser], [[x[1-9a-b].o -DCC_IS_CXX=$CC_IS_CXX main.cc]])
 AT_PARSER_CHECK([parser], [0], [[expout]])

 m4_popdef([AT_TEST])
@@ -1,4 +1,4 @@
-# Checking the Bison scanner.                    -*- Autotest -*-
+# Checking the Bison reader.                    -*- Autotest -*-

 # Copyright (C) 2002-2015, 2018-2020 Free Software Foundation, Inc.

@@ -78,10 +78,13 @@ AT_CLEANUP
 ## Invalid inputs.  ##
 ## ---------------- ##

+# The truly bad guys no human would write, but easily uncovered by
+# fuzzers.
 AT_SETUP([Invalid inputs])

 AT_DATA([input.y],
 [[\000\001\002\377?
+"\000"
 %%
 ?
 default: 'a' }
@@ -92,21 +95,50 @@ default: 'a' }
 ]])
 AT_PERL_REQUIRE([[-pi -e 's/\\(\d{3})/chr(oct($1))/ge' input.y]])

-AT_BISON_CHECK([input.y], [1], [],
+AT_BISON_CHECK([-fcaret input.y], [1], [], [stderr])
+
+# Autotest's diffing, when there are NUL bytes, just reports "binary
+# files differ".  So don't leave NUL bytes.
+AT_PERL_CHECK([[-p -e 's{([\0\377])}{sprintf "\\x%02x", ord($1)}ge' stderr]], [],
 [[input.y:1.1-2: error: invalid characters: '\0\001\002\377?'
-input.y:3.1: error: invalid character: '?'
-input.y:4.14: error: invalid character: '}'
-input.y:5.1: error: invalid character: '%'
-input.y:5.2: error: invalid character: '&'
-input.y:6.1-17: error: invalid directive: '%a-does-not-exist'
-input.y:7.1: error: invalid character: '%'
-input.y:7.2: error: invalid character: '-'
-input.y:8.1-9.0: error: missing '%}' at end of file
+    1 | \x00\xff?
+      | ^~
+input.y:2.2: error: invalid null character
+    2 | "\x00"
+      |  ^
+input.y:4.1: error: invalid character: '?'
+    4 | ?
+      | ^
+input.y:5.14: error: invalid character: '}'
+    5 | default: 'a' }
+      |              ^
+input.y:6.1: error: invalid character: '%'
+    6 | %&
+      | ^
+input.y:6.2: error: invalid character: '&'
+    6 | %&
+      |  ^
+input.y:7.1-17: error: invalid directive: '%a-does-not-exist'
+    7 | %a-does-not-exist
+      | ^~~~~~~~~~~~~~~~~
+input.y:8.1: error: invalid character: '%'
+    8 | %-
+      | ^
+input.y:8.2: error: invalid character: '-'
+    8 | %-
+      |  ^
+input.y:9.1-10.0: error: missing '%}' at end of file
+    9 | %{
+      | ^~
 ]])

 AT_CLEANUP


+## ------------------------ ##
+## Invalid inputs with {}.  ##
+## ------------------------ ##
+
 AT_SETUP([Invalid inputs with {}])

 # We used to SEGV here.  See
@@ -788,6 +820,33 @@ input.y:3.8-10: note: previous declaration
 AT_CLEANUP


+## ---------------- ##
+## EOF redeclared.  ##
+## ---------------- ##
+
+AT_SETUP([EOF redeclared])
+
+# We used to crash when redefining a token after having defined EOF.
+# See https://lists.gnu.org/r/bug-bison/2020-08/msg00008.html.
+
+AT_DATA([[input.y]],
+[[%token FOO BAR FOO 0
+%%
+input: %empty
+]])
+
+AT_BISON_CHECK([-fcaret input.y], [0], [],
+[[input.y:1.16-18: warning: symbol FOO redeclared [-Wother]
+    1 | %token FOO BAR FOO 0
+      |                ^~~
+input.y:1.8-10: note: previous declaration
+    1 | %token FOO BAR FOO 0
+      |        ^~~
+]])
+
+AT_CLEANUP
+
+
 ## --------------------------- ##
 ## Symbol class redefinition.  ##
 ## --------------------------- ##
@@ -1224,12 +1283,12 @@ AT_TEST([[%token foo "foo"
 %%
 exp: foo;
 ]],
-[[input.y:3.7-11: error: %type redeclaration for foo
+[[input.y:3.13-15: error: %type redeclaration for foo
    3 | %type <baz> foo
-      |       ^~~~~
-input.y:2.7-11: note: previous declaration
+      |             ^~~
+input.y:2.13-17: note: previous declaration
    2 | %type <bar> "foo"
-      |       ^~~~~
+      |             ^~~~~
 ]])

 AT_TEST([[%token foo "foo"
@@ -1336,11 +1395,6 @@ AT_CLEANUP
 AT_SETUP([Torturing the Scanner])

 AT_BISON_OPTION_PUSHDEFS
-AT_DATA([input.y], [])
-AT_BISON_CHECK([input.y], [1], [],
-[[input.y:1.1: error: unexpected end of file
-]])
-

 AT_DATA([input.y],
 [{}
@@ -2447,6 +2501,99 @@ input.y:5.19: error: invalid character after \-escape: \001
 AT_CLEANUP


+## ------------------------ ##
+## Unexpected end of file.  ##
+## ------------------------ ##
+
+AT_SETUP([[Unexpected end of file]])
+
+
+AT_DATA([input.y], [])
+AT_BISON_CHECK([-fcaret input.y], [1], [],
+[[input.y:1.1: error: unexpected end of file
+]])
+
+
+AT_DATA_NO_FINAL_EOL([char.y],
+[[%token FOO ']])
+
+AT_BISON_CHECK([-fcaret char.y], [1], [],
+[[char.y:1.12: error: missing "'" at end of file
+    1 | %token FOO '
+      |            ^
+char.y:1.12: error: empty character literal
+    1 | %token FOO '
+      |            ^
+]])
+
+
+AT_DATA_NO_FINAL_EOL([escape-in-char.y],
+[[%token FOO '\]])
+
+AT_BISON_CHECK([-fcaret escape-in-char.y], [1], [],
+[[escape-in-char.y:1.12-13: error: missing '?\'' at end of file
+    1 | %token FOO '\
+      |            ^~
+escape-in-char.y:1.14: error: unexpected end of file
+    1 | %token FOO '\
+      |              ^
+]])
+
+
+AT_DATA_NO_FINAL_EOL([string.y],
+[[%token FOO "]])
+
+AT_BISON_CHECK([-fcaret string.y], [1], [],
+[[string.y:1.12: error: missing '"' at end of file
+    1 | %token FOO "
+      |            ^
+string.y:1.13: error: unexpected end of file
+    1 | %token FOO "
+      |             ^
+]])
+
+
+AT_DATA_NO_FINAL_EOL([escape-in-string.y],
+[[%token FOO "\]])
+
+AT_BISON_CHECK([-fcaret escape-in-string.y], [1], [],
+[[escape-in-string.y:1.12-13: error: missing '?"' at end of file
+    1 | %token FOO "\
+      |            ^~
+escape-in-string.y:1.14: error: unexpected end of file
+    1 | %token FOO "\
+      |              ^
+]])
+
+
+AT_DATA_NO_FINAL_EOL([tstring.y],
+[[%token FOO _("]])
+
+AT_BISON_CHECK([-fcaret tstring.y], [1], [],
+[[tstring.y:1.12-14: error: missing '")' at end of file
+    1 | %token FOO _("
+      |            ^~~
+tstring.y:1.15: error: unexpected end of file
+    1 | %token FOO _("
+      |               ^
+]])
+
+
+AT_DATA_NO_FINAL_EOL([escape-in-tstring.y],
+[[%token FOO _("\]])
+
+AT_BISON_CHECK([-fcaret escape-in-tstring.y], [1], [],
+[[escape-in-tstring.y:1.12-15: error: missing '?")' at end of file
+    1 | %token FOO _("\
+      |            ^~~~
+escape-in-tstring.y:1.16: error: unexpected end of file
+    1 | %token FOO _("\
+      |                ^
+]])
+
+AT_CLEANUP
+
+
 ## ------------------------- ##
 ## LAC: Errors for %define.  ##
 ## ------------------------- ##
@@ -351,7 +351,7 @@ AT_TOKEN_CTOR_IF(
 [m4_pushdef([AT_LOC], [[(]AT_NAME_PREFIX[lloc)]])
 m4_pushdef([AT_VAL], [[(]AT_NAME_PREFIX[lval)]])
 m4_pushdef([AT_YYLEX_FORMALS],     [])
- m4_pushdef([AT_YYLEX_RETURN],      [yy::parser::symbol_type])
+ m4_pushdef([AT_YYLEX_RETURN],      [AT_NAMESPACE::parser::symbol_type])
 m4_pushdef([AT_YYLEX_ARGS],        [])
 m4_pushdef([AT_USE_LEX_ARGS],      [])
 m4_pushdef([AT_YYLEX_PRE_FORMALS], [])
@@ -390,6 +390,7 @@ AT_LOCATION_TYPE_SPAN_IF(


 AT_GLR_IF([AT_KEYWORDS([glr])])
+AT_PUSH_IF([AT_KEYWORDS([push])])
 ])# _AT_BISON_OPTION_PUSHDEFS


@@ -759,7 +759,7 @@ AT_TEST([x1],
         ])

 # Check the CPP guard and Doxyen comments.
-AT_CHECK([sed -ne 's/#line [0-9]\+ "/#line "/p;/INCLUDED/p;/\\file/{p;n;p;}' out/include/ast/loc.hh], [],
+AT_CHECK([[sed -ne 's/#line [0-9][0-9]* "/#line "/p;/INCLUDED/p;/\\file/{p;n;p;}' out/include/ast/loc.hh]], [],
 [[ ** \file bar/include/ast/loc.hh
 ** Define the x1::location class.
 #ifndef YY_YY_BAR_INCLUDE_AST_LOC_HH_INCLUDED
@@ -771,7 +771,7 @@ AT_CHECK([sed -ne 's/#line [0-9]\+ "/#line "/p;/INCLUDED/p;/\\file/{p;n;p;}' out
 #endif // !YY_YY_BAR_INCLUDE_AST_LOC_HH_INCLUDED
 ]])

-AT_CHECK([sed -ne 's/^#line [0-9]\+ "/#line "/p;/INCLUDED/p;/\\file/{p;n;p;}' out/x1.hh], [],
+AT_CHECK([[sed -ne 's/^#line [0-9][0-9]* "/#line "/p;/INCLUDED/p;/\\file/{p;n;p;}' out/x1.hh]], [],
 [[ ** \file bar/x1.hh
 ** Define the x1::parser class.
 #ifndef YY_YY_BAR_X1_HH_INCLUDED
Author	SHA1	Message	Date
Akim Demaille	7a11a9308c	version 3.7.4 * NEWS: Record release date.	2020-11-14 12:04:26 +01:00
Akim Demaille	d8cc6b073e	c++: shorten the assertions that check whether tokens are correct Before: YY_ASSERT (tok == token::YYEOF \|\| tok == token::YYerror \|\| tok == token::YYUNDEF \|\| tok == 120 \|\| tok == 49 \|\| tok == 50 \|\| tok == 51 \|\| tok == 52 \|\| tok == 53 \|\| tok == 54 \|\| tok == 55 \|\| tok == 56 \|\| tok == 57 \|\| tok == 97 \|\| tok == 98); After: YY_ASSERT (tok == token::YYEOF \|\| (token::YYerror <= tok && tok <= token::YYUNDEF) \|\| tok == 120 \|\| (49 <= tok && tok <= 57) \|\| (97 <= tok && tok <= 98)); Clauses are now also wrapped on several lines. This is nicer to read and diff, but also avoids pushing Visual C++ to its arbitrary limits (640K and lines of 16380 bytes ought to be enough for anybody, otherwise make an C2026 error). The useless parens are there for the dummy warnings about precedence (in the future, will we also have to put parens in `1+23`?). data/skeletons/variant.hh (_b4_filter_tokens, b4_tok_in, b4_tok_in): New. (_b4_token_constructor_define): Use them.	2020-11-13 06:17:52 +01:00
Akim Demaille	0264b4bca0	c++: don't glue functions together * data/skeletons/bison.m4 (b4_type_foreach): Accept a separator. * data/skeletons/c++.m4: Use it. And fix an incorrect comment.	2020-11-13 06:17:52 +01:00
Akim Demaille	8b424b865e	lalr1.cc: YY_ASSERT should use api.prefix Working on the previous commit I realized that YY_ASSERT was used in the generated headers, so must follow api.prefix to avoid clashes when multiple C++ parser with variants are used. Actually many more macros should obey api.prefix (YY_CPLUSPLUS, YY_COPY, etc.). There was no complaint so far, so it's not urgent enough for 3.7.4, but it should be addressed in 3.8. * data/skeletons/variant.hh (b4_assert): New. Use it. * tests/local.at (AT_YYLEX_RETURN): Fix. * tests/headers.at: Make sure variant-based C++ parsers are checked too. This test did find that YY_ASSERT escaped renaming (before the fix in this commit).	2020-11-13 06:17:52 +01:00
Akim Demaille	f4431ea115	c++: don't use YY_ASSERT at all if parse.assert is disabled In some extreme situations (about 800 tokens), we generate a single-line assertion long enough for Visual C++ to discard the end of the line, thus falling into parse ends for the missing `);`. On a shorter example: YY_ASSERT (tok == token::TOK_YYEOF \|\| tok == token::TOK_YYerror \|\| tok == token::TOK_YYUNDEF \|\| tok == token::TOK_ASSIGN \|\| tok == token::TOK_MINUS \|\| tok == token::TOK_PLUS \|\| tok == token::TOK_STAR \|\| tok == token::TOK_SLASH \|\| tok == token::TOK_LPAREN \|\| tok == token::TOK_RPAREN); Whether NDEBUG is used or not is irrelevant, the parser dies anyway. Reported by Jot Dot <[email protected]>. https://lists.gnu.org/r/bug-bison/2020-11/msg00002.html We should avoid emitting lines so long. We probably should also use a range-based assertion (with extraneous parens to pacify fascist compilers): YY_ASSERT ((token::TOK_YYEOF <= tok && tok <= token::TOK_YYUNDEF) \|\| (token::TOK_ASSIGN <= tok && ...) But anyway, we should simply not emit this assertion at all when not asked for. * data/skeletons/variant.hh: Do not define, nor use, YY_ASSERT when it is not enabled.	2020-11-13 06:17:52 +01:00
Akim Demaille	fe8c36ddca	c++: style: follow the Bison m4 quoting pattern * data/skeletons/variant.hh: here.	2020-11-13 06:17:24 +01:00
Akim Demaille	21c147b6e5	yacc.c: provide the Bison version as an integral macro Suggested by Balazs Scheidler. https://github.com/akimd/bison/issues/55 * src/muscle-tab.c (muscle_init): Move/rename `b4_version` to/as... * src/output.c (prepare): `b4_version_string`. Also define `b4_version`. * data/skeletons/bison.m4, data/skeletons/c.m4, data/skeletons/d.m4, * data/skeletons/java.m4: Adjust. * doc/bison.texi: Document it.	2020-11-11 09:08:57 +01:00
Akim Demaille	d3c575a6c6	regen	2020-11-11 08:47:23 +01:00
Akim Demaille	d8b49e2b73	style: make conversion of version string to int public * src/parse-gram.y (str_to_version): Rename as/move to... * src/strversion.h, src/strversion.c (strversion_to_int): these new files.	2020-11-11 08:47:23 +01:00
Akim Demaille	14c65a35f0	%require: accept version numbers with three parts ("3.7.4") * src/parse-gram.y (str_to_version): Support three parts. * data/skeletons/location.cc, data/skeletons/stack.hh: Adjust.	2020-11-11 08:47:23 +01:00
Todd C. MillerandAkim Demaille	c47bb87f9f	yacc.c: fix #definition of YYEMPTY When generating a C parser, YYEMPTY is present in enum yytokentype but there is no corresponding #define like there is for the other values. There is a special case for YYEMPTY in b4_token_enums but no corresponding case in b4_token_defines. * data/skeletons/c.m4 (b4_token_defines): Do define YYEMPTY.	2020-11-11 08:47:21 +01:00
Akim Demaille	98c35e0025	gnulib: update	2020-11-10 07:56:13 +01:00
Akim Demaille	bd6b046ce7	doc: fix incorrect section title Reported by Gaurav Singh <[email protected]>. https://lists.gnu.org/r/bug-bison/2020-11/msg00000.html * doc/bison.texi (Rpcalc Expr): Rename as... (Rpcalc Exp): this, as the nterm is named 'exp'.	2020-11-01 09:12:27 +01:00
Nick GassonandAkim Demaille	7c6e7bd300	doc: minor grammar fixes in counterexamples section * doc/bison.texi: Minor fixes in counterexamples section.	2020-10-28 06:36:43 +01:00
Akim Demaille	3cba59dd7f	doc: fix typo * README: here.	2020-10-14 21:12:04 +02:00
Akim Demaille	a15879c623	maint: post-release administrivia * NEWS: Add header line for next release. * .prev-version: Record previous version. * cfg.mk (old_NEWS_hash): Auto-update.	2020-10-13 07:23:28 +02:00
Akim Demaille	5d501ee728	version 3.7.3 * NEWS: Record release date.	2020-10-13 07:01:24 +02:00
Akim Demaille	bc5e4541da	build: don't link bison against libreadline Reported by Paul Smith <[email protected]>. https://lists.gnu.org/r/bug-bison/2020-10/msg00001.html * src/local.mk (src_bison_LDADD): here.	2020-10-13 06:57:33 +02:00
Akim Demaille	567d1eaa19	gnulib: update	2020-10-13 06:46:06 +02:00
Akim Demaille	c08e0863be	glr.cc: fix: use symbol_name * data/skeletons/glr.cc: here.	2020-09-27 09:22:02 +02:00
Akim Demaille	541943ee04	build: fix a concurrent build issue in examples Reported by Thomas Deutschmann <[email protected]>. https://lists.gnu.org/r/bug-bison/2020-09/msg00010.html * examples/c/lexcalc/local.mk: scan.o depends on parse.[ch].	2020-09-06 10:08:22 +02:00
Akim Demaille	dcdd119f69	maint: post-release administrivia * NEWS: Add header line for next release. * .prev-version: Record previous version. * cfg.mk (old_NEWS_hash): Auto-update.	2020-09-05 18:31:25 +02:00
Akim Demaille	a0bc06b703	version 3.7.2 * NEWS: Record release date.	2020-09-05 18:06:16 +02:00
Akim Demaille	5e33dfe59d	build: disable syntax-check warning error_message_uppercase etc/bench.pl.in-419-static int yylex (@{[is_pure (@directive) ? "YYSTYPE yylvalp" : "void"]}); cfg.mk: here.	2020-09-05 17:59:56 +02:00
Akim Demaille	2a4e9a358f	gnulib: update	2020-09-05 17:44:38 +02:00
Akim Demaille	f7b642cff7	build: fix incorrect dependencies Commit `af000bab11` ("doc: work around Texinfo 6.7 bug"), published in 3.4.91, added a dependency on the "all" target. This is a super bad idea, since "make all" will run this target before "all", which builds bison. It turns out that this new dependency actually needed bison to be built. So all the regular process (i) build $(BUILT_SOURCES) and then (ii) build bison, was wrecked since some of the $(BUILT_SOURCES) depended on bison... It was "easy" to see in the logs of "make V=1" because we were building bison files (such as src/files.o) before displaying the banner for "all-recursive". With this fix, we finally get again the proper sequence: rm -f examples/c/reccalc/scan.stamp examples/c/reccalc/scan.stamp.tmp /opt/local/libexec/gnubin/mkdir -p examples/c/reccalc touch examples/c/reccalc/scan.stamp.tmp flex -oexamples/c/reccalc/scan.c --header=examples/c/reccalc/scan.h ./examples/c/reccalc/scan.l mv examples/c/reccalc/scan.stamp.tmp examples/c/reccalc/scan.stamp rm -f lib/fcntl.h-t lib/fcntl.h && \ { echo '/* DO NOT EDIT! GENERATED AUTOMATICALLY! /'; \ ... } > lib/fcntl.h-t && \ mv lib/fcntl.h-t lib/fcntl.h ... mv -f lib/alloca.h-t lib/alloca.h make all-recursive Reported by Mingli Yu <[email protected]>. https://github.com/akimd/bison/issues/31 https://lists.gnu.org/r/bison-patches/2020-05/msg00055.html Reported by Claudio Calvelli <[email protected]>. https://lists.gnu.org/r/bug-bison/2020-09/msg00001.html https://bugs.gentoo.org/716516 doc/local.mk (all): Rename as... (all-local): this. So that we don't compete with BUILT_SOURCES.	2020-09-05 17:42:20 +02:00
Akim Demaille	3da17724ad	doc: updates * NEWS, TODO: here.	2020-09-02 21:37:23 +02:00
Akim Demaille	68e3e442f9	gnulib: update	2020-08-30 17:32:43 +02:00
Akim Demaille	e432619d11	tests: beware of sed portability issues Reported by David Laxer <[email protected]>. https://lists.gnu.org/r/bug-bison/2020-08/msg00027.html * tests/output.at: Don't use + with sed. While at it, fix a quotation problem hidden by the use of '#'.	2020-08-30 17:16:18 +02:00
Akim Demaille	a1b7fef045	c: always use YYMALLOC/YYFREE Reported by Kovalex <[email protected]>. https://lists.gnu.org/r/bug-bison/2020-08/msg00015.html * data/skeletons/yacc.c: Don't make direct calls to malloc/free. * tests/calc.at: Check it.	2020-08-30 10:05:18 +02:00
Akim Demaille	067e35a8be	build: beware of POSIX mode Reported by Dennis Clarke. https://lists.gnu.org/r/bug-bison/2020-08/msg00013.html * examples/d/local.mk, examples/java/calc/local.mk, * examples/java/simple/local.mk: Pass bison's options before its argument, in case we're in POSIX mode.	2020-08-30 09:38:05 +02:00
Akim Demaille	0522047c96	doc: history of api.prefix Reported by Matthew Fernandez <[email protected]>. https://lists.gnu.org/r/help-bison/2020-08/msg00015.html * doc/bison.texi (api.prefix): We move to {} in 3.0.	2020-08-30 09:29:00 +02:00
Akim Demaille	3724b50ef9	CI: intel moved the script for ICC * .travis.yml: Adjust.	2020-08-11 07:18:48 +02:00
Akim Demaille	b801b7b670	fix: unterminated \-escape An assertion failed when the last character is a '\' and we're in a character or a string. Reported by Agency for Defense Development. https://lists.gnu.org/r/bug-bison/2020-08/msg00009.html * src/scan-gram.l: Catch unterminated escapes. * tests/input.at (Unexpected end of file): New.	2020-08-08 07:53:33 +02:00
Akim Demaille	b7aab2dbad	fix: crash when redefining the EOF token Reported by Agency for Defense Development. https://lists.gnu.org/r/bug-bison/2020-08/msg00008.html On an empty such as %token FOO BAR FOO 0 %% input: %empty we crash because when we find FOO 0, we decrement ntokens (since FOO was discovered to be EOF, which is already known to be a token, so we increment ntokens for it, and need to cancel this). This "works well" when EOF is properly defined in one go, but here it is first defined and later only assign token code 0. In the meanwhile BAR was given the token number that we just decremented. To fix this, assign symbol numbers after parsing, not during parsing, so that we also saw all the explicit token codes. To maintain the current numbers (I'd like to keep no difference in the output, not just equivalence), we need to make sure the symbols are numbered in the same order: that of appearance in the source file. So we need the locations to be correct, which was almost the case, except for nterms that appeared several times as LHS (i.e., several times as "foo: ..."). Fixing the use of location_of_lhs sufficed (it appears it was intended for this use, but its implementation was unfinished: it was always set to "false" only). * src/symtab.c (symbol_location_as_lhs_set): Update location_of_lhs. (symbol_code_set): Remove broken hack that decremented ntokens. (symbol_class_set, dummy_symbol_get): Don't set number, ntokens and nnterms. (symbol_check_defined): Do it. (symbols): Don't count nsyms here. Actually, don't count nsyms at all: let it be done in... * src/reader.c (check_and_convert_grammar): here. Define nsyms from ntokens and nnterms after parsing. * tests/input.at (EOF redeclared): New. * examples/c/bistromathic/bistromathic.test: Adjust the traces: in "%nterm <double> exp %% input: ...", exp used to be numbered before input.	2020-08-07 07:30:06 +02:00
Akim Demaille	89e42ffb4b	style: fix missing space before paren * cfg.mk (_space_before_paren_exempt): Be less laxist. * src/output.c, src/reader.c: Fix space before paren issues. Pacify the warnings where applicable.	2020-08-07 07:30:06 +02:00
Akim Demaille	6aae4a7378	style: fix comments and more debug trace * src/location.c, src/symtab.h, src/symtab.c: here.	2020-08-07 07:30:06 +02:00
Akim Demaille	7d4a4300c2	style: more uses of const * src/symtab.c: here.	2020-08-07 07:30:06 +02:00
Akim Demaille	31d4ec28bd	bench: fix support for pure parser * etc/bench.pl.in (is_pure): New. (generate_grammar_calc): Use code provides where needed. Use is_pure to call yylex properly. Coding style fixes.	2020-08-07 07:29:16 +02:00
Akim Demaille	0a5bfb4fda	portability: multiple typedefs Older versions of GCC (4.1.2 here) don't like repeated typedefs. CC src/bison-parse-simulation.o src/parse-simulation.c:61: error: redefinition of typedef 'parse_state' src/parse-simulation.h:74: error: previous declaration of 'parse_state' was here make: *** [Makefile:7876: src/bison-parse-simulation.o] Error 1 Reported by Nelson H. F. Beebe. * src/parse-simulation.c (parse_state): Don't typedef, parse-simulation.h did it already.	2020-08-03 07:30:35 +02:00
Akim Demaille	12d0b15679	style: revert "avoid warnings with GCC 4.6" This reverts commit `d0bec3175f` (which should have read "We have a clash...", not "With have a clash..."). Now that `max()` was renamed `max_int()`, we can use `max` again, as elsewhere in the code. * src/counterexample.c (visited_hasher): Alpha reconversion.	2020-08-02 10:20:23 +02:00
Akim Demaille	cb7dcb011e	maint: post-release administrivia * NEWS: Add header line for next release. * .prev-version: Record previous version. * cfg.mk (old_NEWS_hash): Auto-update.	2020-08-02 09:32:34 +02:00
Akim Demaille	71579c7219	version 3.7.1 * NEWS: Record release date.	2020-08-02 09:10:02 +02:00
Akim Demaille	2f8a874215	portability: we use termios.h and sys/ioctl.h Reported by Maarten De Braekeleer. https://lists.gnu.org/r/bison-patches/2020-07/msg00079.html * bootstrap.conf (gnulib_modules): Add termios and sys_ioctl.	2020-08-02 08:36:49 +02:00
Maarten De BraekeleerandAkim Demaille	ad6f600bb1	portability: rename accept to acceptsymbol because of MSVC MSVC already defines this symbol. * src/symtab.h, src/symtab.c (accept): Rename as... (acceptsymbol): this. Adjust dependencies.	2020-08-02 08:32:57 +02:00
Akim Demaille	de4f41eab7	regen	2020-08-02 08:32:57 +02:00
Maarten De BraekeleerandAkim Demaille	e73f086b0d	portability: use CHAR_LITERAL instead of CHAR because MSVC defines CHAR * src/parse-gram.y, src/scan-gram.l: here.	2020-08-02 08:32:57 +02:00
Maarten De BraekeleerandAkim Demaille	8cf098415e	portability: use INT_LITERAL instead of INT because MSVC defines INT It is defined as a typedef, not a macro. https://lists.gnu.org/r/bison-patches/2020-08/msg00001.html * src/parse-gram.y, src/scan-gram.l: here.	2020-08-02 08:32:30 +02:00
Akim Demaille	977e19840d	portability: beware of max () with MSVC Reported by Maarten De Braekeleer. https://lists.gnu.org/r/bison-patches/2020-07/msg00080.html We don't want to use gnulib's min and max macros, since we use function calls in min/max arguments. * src/location.c (max_int, min_int): Move to... * src/system.h: here. * src/counterexample.c, src/derivation.c: Use max_int instead of max.	2020-08-02 08:19:35 +02:00
Akim Demaille	d975c2f76e	libtextstyle: be sure to have ostream_printf and hyperlink support Older versions of libtextstyle do not support them, rule them out. Reported by Lars Wendler https://lists.gnu.org/r/bug-bison/2020-07/msg00030.html and by Arnold Robbins https://lists.gnu.org/r/bug-bison/2020-07/msg00041.html and https://lists.gnu.org/mailman/private/gawk-devel/2020-July/003988.html and by Nelson H. F. Beebe https://lists.gnu.org/mailman/private/gawk-devel/2020-July/003993.html With support from Bruno Haible in gnulib https://lists.gnu.org/r/bug-gnulib/2020-08/msg00000.html thread starting at https://lists.gnu.org/r/bug-gnulib/2020-07/msg00148.html * configure.ac: Require libtextstyle 0.20.5. * gnulib: Update.	2020-08-02 08:19:35 +02:00
Akim Demaille	0676801b8c	CI: comment changes	2020-08-01 10:02:44 +02:00
Akim Demaille	82aa96e9b1	regen	2020-08-01 08:54:46 +02:00
Akim Demaille	cb65553449	diagnostics: better location for type redeclarations From foo.y:1.7-11: error: %type redeclaration for bar 1 \| %type <foo> bar bar \| ^~~~~ foo.y:1.7-11: note: previous declaration 1 \| %type <foo> bar bar \| ^~~~~ to foo.y:1.17-19: error: %type redeclaration for bar 1 \| %type <foo> bar bar \| ^~~ foo.y:1.13-15: note: previous declaration 1 \| %type <foo> bar bar \| ^~~ * src/symlist.h, src/symlist.c (symbol_list_type_set): There's no need for the tag's location, use that of the symbol. * src/parse-gram.y: Adjust. * tests/input.at: Adjust.	2020-08-01 08:54:46 +02:00
Akim Demaille	f47a1bd622	todo: updates for D	2020-07-30 07:14:57 +02:00
Akim Demaille	205d372c68	cex: style: comment changes * src/parse-simulation.c: here.	2020-07-29 20:00:59 +02:00
Akim Demaille	07a1243b40	cex: style: prefer "res" for the returned value * src/derivation.c (derivation_new): here.	2020-07-29 20:00:59 +02:00
Akim Demaille	ece343d2c2	cex: style: prefer FOO_print to print_FOO * src/state-item.h, src/state-item.c (print_state_item): Rename as... (state_item_print): this. * src/counterexample.c (print_counterexample): Rename as... (counterexample_print): this.	2020-07-29 20:00:27 +02:00
Akim Demaille	be95a4fe29	scanner: don't crash on strings containing a NUL byte We crash if the input contains a string containing a NUL byte. Reported by Suhwan Song. https://lists.gnu.org/r/bug-bison/2020-07/msg00051.html * src/flex-scanner.h (STRING_FREE): Avoid accidental use of last_string. * src/scan-gram.l: Don't call STRING_FREE without calling STRING_FINISH first. * tests/input.at (Invalid inputs): Check that case.	2020-07-28 19:01:48 +02:00
Akim Demaille	6accee7716	doc: refer to cex from sections dealing with conflicts The documentation about -Wcex should be put forward. * doc/bison.texi: Refer to -Wcex from the sections about conflicts.	2020-07-28 07:45:07 +02:00
Akim Demaille	e63f22703e	doc: factor ifnottex/iftex examples * doc/bison.texi: Factor the common bits out of ifnottex/iftex.	2020-07-28 07:45:07 +02:00
Akim Demaille	fa390dc311	doc: fix colors The original Texinfo macros introducing colors were made for diagnostics, which are printed in bold. So by copy-paste accident the styles we introduced for counterexamples were also in bold. They should not. * doc/bison.texi: Separate the styling of diagnostics from the styling for counterexamples. Don't use bold in the latter case.	2020-07-28 07:45:07 +02:00
Akim Demaille	17fdf5eca2	doc: fixes * doc/bison.texi: Fix spello. Fix missing colors, and factor.	2020-07-28 07:45:07 +02:00
Akim Demaille	72b3c1a673	maint: post-release administrivia * NEWS: Add header line for next release. * .prev-version: Record previous version. * cfg.mk (old_NEWS_hash): Auto-update.	2020-07-23 20:15:38 +02:00
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