c.m4 contains a definition of _Noreturn which is modeled after
gnulib's lib/_Noreturn.h. The latter was recently
changed (b61bf2f0e8) to not using
[[noreturn]] at all, because the uses of _Noreturn in gnulib are
sometimes incompatible with the rules of [[noreturn]].
As a result glr.cc started to use _Noreturn in C++, which clang
refuses (all the glr.cc tests currently fail with Clang++).
* data/skeletons/c.m4 (b4_attribute_define): Restore the definition of
_Noreturn as [[noreturn]] in modern C++.
The generated code uses _Noreturn in places where [[noreturn]] is
valid.
Reported by Paul Eggert.
* src/getargs.c: We don't need it anyway, since we use _Noreturn.
* data/skeletons/c.m4: While at it, update the definition of _Noreturn
stolen from gnulib.
For instance test 386, "glr.cc api.value.type={double}":
types.at:366: $CXX $CXXFLAGS $CPPFLAGS $LDFLAGS -o test test.cc $LIBS
stderr:
test.cc: In function 'ptrdiff_t yysplitStack(yyGLRStack*, ptrdiff_t)':
test.cc:490:4: error: 'PTRDIFF_MAX' was not declared in this scope
(PTRDIFF_MAX < SIZE_MAX ? PTRDIFF_MAX : YY_CAST (ptrdiff_t, SIZE_MAX))
^
test.cc:1805:37: note: in expansion of macro 'YYSIZEMAX'
ptrdiff_t half_max_capacity = YYSIZEMAX / 2 / state_size;
^~~~~~~~~
test.cc:490:4: note: suggested alternative: '__PTRDIFF_MAX__'
(PTRDIFF_MAX < SIZE_MAX ? PTRDIFF_MAX : YY_CAST (ptrdiff_t, SIZE_MAX))
^
test.cc:1805:37: note: in expansion of macro 'YYSIZEMAX'
ptrdiff_t half_max_capacity = YYSIZEMAX / 2 / state_size;
^~~~~~~~~
The failing tests are using glr.cc only, which I don't understand, the
problem is rather in glr.c, so I would expect glr.c tests to also fail.
Reported by Bruno Haible.
https://lists.gnu.org/archive/html/bug-bison/2020-05/msg00053.html
* data/skeletons/yacc.c: Move the block that defines
YYPTRDIFF_T/YYPTRDIFF_MAXIMUM, YYSIZE_T/YYSIZE_MAXIMUM, and
YYSIZEOF to...
* data/skeletons/c.m4 (b4_sizes_types_define): Here.
(b4_c99_int_type): Also take care of the #undefinition of short.
* data/skeletons/yacc.c, data/skeletons/glr.c: Use
b4_sizes_types_define.
* data/skeletons/glr.c: Adjust to use YYPTRDIFF_T/YYPTRDIFF_MAXIMUM,
YYSIZE_T/YYSIZE_MAXIMUM.
I have been hesitating a lot before doing it ---after all the user
must not use this kind, so what's the point of showing it in
yytoken_kind_t. And eventually I chose to play it safe with the
typing system and make it possible to use yytoken_kind_t for all the
tokens, even the "empty token".
* data/skeletons/c.m4: Give an id and a tag to YYEMPTY.
(b4_token_enums): Define YYEMPTY.
* data/skeletons/c++.m4 (b4_token_enums): Define YYEMPTY.
* data/skeletons/glr.c, data/skeletons/glr.cc, data/skeletons/yacc.c:
(YYEMPTY): Remove.
Use b4_symbol(-2, id) instead.
Currently EOF is handled in an adhoc way, with a #define YYEOF 0 in
the implementation file. As a result, the user has to define her own
EOF token if she wants to use it, which is a pity.
Give the $end token a visible kind name, YYEOF. Except that in C,
where enums are not scoped, we would have collisions between all the
definitions of YYEOFs in the header files, so in C, make it
<api.PREFIX>EOF.
* data/skeletons/c.m4 (YYEOF): Override its name to avoid collisions.
Unless the user already gave it a different name.
* data/skeletons/glr.c (YYEOF): Remove.
Use ]b4_symbol(0, [id])[ instead.
Add support for "pre_epilogue", for glr.cc.
* data/skeletons/glr.cc: Remove dead code (never emitted #undefs).
* data/skeletons/yacc.c
* src/parse-gram.c
* src/reader.c
* src/symtab.c
* tests/actions.at
* tests/input.at
* data/skeletons/bison.m4 (b4_symbol_token_kind): Give a definition to
$undefined.
(b4_token_visible_if): $undefined has an id.
* src/output.c (prepare_symbol_definitions): Stop lying: $undefined
_is_ a token.
* tests/input.at: Adjust.
* data/skeletons/bison.m4 (b4_symbol_kind): Dispatch on the UNDEF
token number rather than its name.
* data/skeletons/c++.m4, data/skeletons/c.m4, data/skeletons/java.m4:
Comment changes.
* data/skeletons/bison.m4, data/skeletons/c++.m4, data/skeletons/c.m4,
* data/skeletons/glr.cc, data/skeletons/lalr1.cc,
* data/skeletons/lalr1.d, data/skeletons/lalr1.java:
Refer to the "kind" of a symbol, not its "type", where appropriate.
Now that yacc.c and glr.c both know yysymbol_type_t, convert the
common routines.
* data/skeletons/c.m4 (yydestruct, yy_symbol_value_print)
(yy_symbol_print): Use yysymbol_type_t instead of int.
* data/skeletons/glr.c: Use yySymbol where appropriate.
* data/skeletons/yacc.c (YY_ACCESSING_SYMBOL): New wrapper around
yystos.
Use it.
* tests/local.at (yyreport_syntax_error): Use yysymbol_type_t where
appropriate.
This is not only cleaner, it also protects us from mixing signed
values (YYEMPTY is #defined as -2) with unsigned types (the
yysymbol_type_t enum is typically compiled as a small unsigned).
For instance GCC 9:
input.c: In function 'yyparse':
input.c:1107:7: error: conversion to 'unsigned int' from 'int'
may change the sign of the result
[-Werror=sign-conversion]
1107 | yyn += yytoken;
| ^~
input.c:1107:10: error: conversion to 'int' from 'unsigned int'
may change the sign of the result
[-Werror=sign-conversion]
1107 | yyn += yytoken;
| ^~~~~~~
input.c:1108:47: error: comparison of integer expressions of
different signedness:
'yytype_int8' {aka 'const signed char'} and
'yysymbol_type_t' {aka 'enum yysymbol_type_t'}
[-Werror=sign-compare]
1108 | if (yyn < 0 || YYLAST < yyn || yycheck[yyn] != yytoken)
| ^~
input.c:702:25: error: operand of ?: changes signedness from 'int'
to 'unsigned int' due to unsignedness of
other operand [-Werror=sign-compare]
702 | #define YYEMPTY (-2)
| ^~~~
input.c:1220:33: note: in expansion of macro 'YYEMPTY'
1220 | yytoken = yychar == YYEMPTY ? YYEMPTY : YYTRANSLATE (yychar);
| ^~~~~~~
input.c:1220:41: error: unsigned conversion from 'int' to
'unsigned int' changes value
from '-2' to '4294967294'
[-Werror=sign-conversion]
1220 | yytoken = yychar == YYEMPTY ? YYEMPTY : YYTRANSLATE (yychar);
| ^
Eventually, it might be interesting to move away from -2 (which is the
only possible negative symbol number) and use the next available
number, to save bits. We could actually even simply use "0" and shift
the rest, which would allow to write "!yytoken" to mean really
"yytoken != YYEMPTY".
* data/skeletons/c.m4 (b4_declare_symbol_enum): Define YYSYMBOL_YYEMPTY.
* data/skeletons/yacc.c: Use it.
* src/parse-gram.y (yyreport_syntax_error): Use YYSYMBOL_YYEMPTY, not
YYEMPTY, when dealing with a symbol.
* tests/regression.at: Adjust.
There's a number of advantage in exposing the symbol (internal)
numbers:
- custom error messages can use them to decide how to represent a
given symbol, or a set of symbols.
- we need something similar in uses of yyexpected_tokens. For
instance, currently, bistromathic's completion() reads:
int ntokens = expected_tokens (line, tokens, YYNTOKENS);
[...]
for (int i = 0; i < ntokens; ++i)
if (tokens[i] == YYTRANSLATE (TOK_VAR))
[...]
else if (tokens[i] == YYTRANSLATE (TOK_FUN))
[...]
else
[...]
- now that it's a compile-time expression, we can easily build static
tables, switch, etc.
- some users depended on the ability to get the token number from a
symbol to write test cases for their scanners. But Bison 3.5
removed the table this feature depended upon (a reverse
yytranslate). Now they can check against the actual symbol number,
without having pay (space and time) a conversion.
See https://lists.gnu.org/r/bug-bison/2020-01/msg00001.html, and
https://lists.gnu.org/archive/html/bug-bison/2020-03/msg00015.html.
- it helps us clearly separate the internal symbol numbers from the
external token numbers, whose difference is sometimes blurred in the
code when values coincide (e.g. "yychar = yytoken = YYEOF").
- it allows us to get rid of ugly macros with inconsistent names such
as YYUNDEFTOK and YYTERROR, and to group related definitions
together.
- similarly it provides a clean access to the $accept symbol (which
proves convenient in a current experimentation of mine with several
%start symbols).
Let's declare this type as a private type (in the *.c file, not
the *.h one). So it does not need to be influenced by the api prefix.
* data/skeletons/bison.m4 (b4_symbol_sid): New.
(b4_symbol): Use it.
* data/skeletons/c.m4 (b4_symbol_enum, b4_declare_symbol_enum): New.
* data/skeletons/yacc.c: Use b4_declare_symbol_enum.
(YYUNDEFTOK, YYTERROR): Remove.
Use the corresponding symbol enum instead.
These macros have been extremely useful when we had to support K&R C,
which we dropped long ago. Now, they merely make the code uselessly
hard to read.
* data/skeletons/c.m4, data/skeletons/glr.c, data/skeletons/glr.cc,
* data/skeletons/yacc.c:
Stop using b4_function_define.
In Java there is no need for N_ and yytranslate_. So instead of
hard-coding the use of N_ in the table of the symbol names, rely on
b4_symbol_translate.
* src/output.c (prepare_symbol_names): Use b4_symbol_translate instead
of N_.
* data/skeletons/c.m4 (b4_symbol_translate): New.
* data/skeletons/lalr1.java (yysymbolName): New.
Use it.
* examples/java/calc/Calc.y: Use parse.error=detailed.
* tests/calc.at: Check parse.error=detailed.
Only parse.error verbose and simple will get the original yytname: the
other options will rely on a different table. So let's move on top of
the yysymbol_name function.
* data/skeletons/c.m4 (yy_symbol_print): Use yysymbol_name.
* data/skeletons/glr.c (yytokenName): Rename as...
(yysymbol_name): this.
The change of naming scheme is unfortunate, but it's definitely glr.c
which is "wrong".
We still have a few old C casts in lalr1.cc, let's get rid of them.
Reported by Frank Heckenbach.
Actually, let's monitor all our casts using easy to grep macros.
Let's use these macros to use the C++ standard casts when we are in
C++.
* data/skeletons/c.m4 (b4_cast_define): New.
* data/skeletons/glr.c, data/skeletons/glr.cc,
* data/skeletons/lalr1.cc, data/skeletons/stack.hh,
* data/skeletons/yacc.c:
Use it and/or its casts.
* tests/actions.at, tests/cxx-type.at,
* tests/glr-regression.at, tests/headers.at, tests/torture.at,
* tests/types.at:
Use YY_CAST instead of C casts.
* configure.ac (warn_cxx): Add -Wold-style-cast.
* doc/bison.texi: Disable it.
Sun C 5.12 defines __SUNPRO_C to 0x5120 but diagnoses
‘__attribute__ ((__unused__))’. Change the ifdefs to use
the same method as Gnulib in this area.
* data/skeletons/c.m4 (YY_ATTRIBUTE): Remove, since
not all attributes were added in the same compiler version.
(YY_ATTRIBUTE_PURE, YY_ATTRIBUTE_UNUSED):
Use specific GCC version for each attribute.
Pay no attention to __SUNPRO_C.
* tests/headers.at (Several parsers): Tighten tests accordingly.
Oracle Solaris Studio 12.3 (Sun C 5.12 2011/11/16) by default does
not conform to C99; it defines __STDC_VERSION__ to be 199409L, so
the Bison code does not include <stdint.h> (not required by C89
amendment 1) even though this compiler does have <stdint.h>. On
this platform <limits.h> defines INT_LEAST8_MAX (POSIX allows
this) so the skeleton got confused and thought that <stdint.h> had
been included even though it wasn’t.
* data/skeletons/c.m4 (b4_c99_int_type_define) [!__PTRDIFF_MAX__]:
Always include <limits.h>.
(YY_STDINT_H): Define when <stdint.h> was included.
All uses of expressions like ‘defined INT_LEAST8_MAX’ changed to
‘defined YY_STDINT_H’, since Sun C 5.12 <limits.h> defines macros
like INT_LEAST8_MAX but does not declare types like int_least8_t.
* data/skeletons/c.m4 (b4_c99_int_type_define): Reorder to put the
signed types first, since they’re simpler and this keeps similar
code closer. For signed types, don’t bother checking whether the
type promotes to int since the type must be signed anyway. For
unsigned types, protect a test like ‘UCHAR_MAX <= INT_MAX’ with
‘!defined __UINT_LEAST8_MAX__’, as otherwise the logic is wrong
for oddball platforms; and once we do that, there should no need
for ‘defined INT_MAX’ so remove that.
A number of portability issues with GCC 4.6 .. 4.9 (inclusive):
input.c:184:7: error: "UCHAR_MAX" is not defined [-Werror=undef]
#elif UCHAR_MAX <= INT_MAX
^
input.c:184:20: error: "INT_MAX" is not defined [-Werror=undef]
#elif UCHAR_MAX <= INT_MAX
^
input.c:202:7: error: "USHRT_MAX" is not defined [-Werror=undef]
#elif USHRT_MAX <= INT_MAX
^
input.c:202:20: error: "INT_MAX" is not defined [-Werror=undef]
#elif USHRT_MAX <= INT_MAX
^
* data/skeletons/c.m4 (b4_c99_int_type_define): Don't assume they are
defined.
That way, glr.c can use it too.
* data/skeletons/c.m4 (b4_int_type):
Do not special-case ‘char’; it’s not worth the trouble,
as clang complains about char subscripts.
(b4_c99_int_type, b4_c99_int_type_define): New macros,
taken from yacc.c.
* data/skeletons/glr.c: Use b4_int_type_define.
* data/skeletons/yacc.c (b4_int_type): Remove, since there’s
no longer any need to redefine it.
Use b4_c99_int_type_define rather than its body.
This patch contains more fixes to prefer signed to unsigned
integer types, as modern tools like 'gcc -fsanitize=undefined'
can check for signed integer overflow but not unsigned overflow.
* NEWS: Document the API change.
* boostrap.conf (gnulib_modules): Add intprops.
* data/skeletons/glr.c: Include stddef.h and stdint.h,
since this skeleton can assume C99 or later.
(YYSIZEMAX): Now signed, and the minimum of SIZE_MAX and PTRDIFF_MAX.
(yybool) [!__cplusplus]: Now signed (which is how bool behaves).
(YYTRANSLATE): Avoid use of unsigned, and make the macro
safe even for values greater than UINT_MAX.
(yytnamerr, struct yyGLRState, struct yyGLRStateSet, struct yyGLRStack)
(yyaddDeferredAction, yyinitStateSet, yyinitGLRStack)
(yyexpandGLRStack, yymarkStackDeleted, yyremoveDeletes)
(yyglrShift, yyglrShiftDefer, yy_reduce_print, yydoAction)
(yyglrReduce, yysplitStack, yyreportTree, yycompressStack)
(yyprocessOneStack, yyreportSyntaxError, yyrecoverSyntaxError)
(yyparse, yy_yypstack, yypstack, yypdumpstack):
* tests/input.at (Torturing the Scanner):
Prefer ptrdiff_t to size_t.
* data/skeletons/c++.m4 (b4_yytranslate_define):
* src/AnnotationList.c (AnnotationList__computePredecessorAnnotations):
* src/AnnotationList.h (AnnotationIndex):
* src/InadequacyList.h (InadequacyListNodeCount):
* src/closure.c (closure_new):
* src/complain.c (error_message, complains, complain_indent)
(complain_args, duplicate_directive, duplicate_rule_directive):
* src/gram.c (nritems, ritem_print, grammar_dump):
* src/ielr.c (ielr_compute_ritem_sees_lookahead_set)
(ielr_item_has_lookahead, ielr_compute_annotation_lists)
(ielr_compute_lookaheads):
* src/location.c (columns, boundary_print, location_print):
* src/muscle-tab.c (muscle_percent_define_insert)
(muscle_percent_define_check_values):
* src/output.c (prepare_rules, prepare_actions):
* src/parse-gram.y (id, handle_require):
* src/reader.c (record_merge_function_type, packgram):
* src/reduce.c (nuseless_productions, nuseless_nonterminals)
(inaccessable_symbols):
* src/relation.c (relation_print):
* src/scan-code.l (variant, variant_table_size, variant_count)
(variant_add, get_at_spec, show_sub_message, show_sub_messages)
(parse_ref):
* src/scan-gram.l (<SC_ESCAPED_STRING,SC_ESCAPED_CHARACTER>)
(scan_integer, convert_ucn_to_byte, handle_syncline):
* src/scan-skel.l (at_complain):
* src/symtab.c (complain_symbol_redeclared)
(complain_semantic_type_redeclared, complain_class_redeclared)
(symbol_class_set, complain_user_token_number_redeclared):
* src/tables.c (conflict_tos, conflrow, conflict_table)
(conflict_list, save_row, pack_vector):
* tests/local.at (AT_YYLEX_DEFINE(c)):
Prefer signed to unsigned integer.
* data/skeletons/lalr1.cc (yy_lac_check_):
* tests/actions.at (_AT_CHECK_PRINTER_AND_DESTRUCTOR):
* tests/local.at (AT_YYLEX_DEFINE(c)):
Omit now-unnecessary casts.
* data/skeletons/location.cc (b4_location_define):
* doc/bison.texi (Mfcalc Lexer, C++ position, C++ location):
Prefer int to unsigned for line and column numbers.
Change example to abort explicitly on memory exhaustion,
and fix an off-by-one bug that led to undefined behavior.
* data/skeletons/stack.hh (stack::operator[]):
Also allow ptrdiff_t indexes.
(stack::pop, slice::slice, slice::operator[]):
Index arg is now ptrdiff_t, not int.
(stack::ssize): New method.
(slice::range_): Now ptrdiff_t, not int.
* data/skeletons/yacc.c (b4_state_num_type): Remove.
All uses replaced by b4_int_type.
(YY_CONVERT_INT_BEGIN, YY_CONVERT_INT_END): New macros.
(yylac, yyparse): Use them around conversions that -Wconversion
would give false alarms about. Omit unnecessary casts.
(yy_stack_print): Use int rather than unsigned, and omit
a cast that doesn’t seem to be needed here any more.
* examples/c++/variant.yy (yylex):
* examples/c++/variant-11.yy (yylex):
Omit no-longer-needed conversions to unsigned.
* src/InadequacyList.c (InadequacyList__new_conflict):
Don’t assume *node_count is unsigned.
* src/output.c (muscle_insert_unsigned_table):
Remove; no longer used.
* NEWS: Mention this.
* data/skeletons/c.m4 (b4_int_type):
Prefer char if it will do, and prefer signed types to unsigned if
either will do.
* data/skeletons/glr.c (yy_reduce_print): No need to
convert rule line to unsigned long.
(yyrecoverSyntaxError): Put action into an int to
avoid GCC warning of using a char subscript.
* data/skeletons/lalr1.cc (yy_lac_check_, yysyntax_error_):
Prefer ptrdiff_t to size_t.
* data/skeletons/yacc.c (b4_int_type):
Prefer signed types to unsigned if either will do.
* data/skeletons/yacc.c (b4_declare_parser_state_variables):
(YYSTACK_RELOCATE, YYCOPY, yy_lac_stack_realloc, yy_lac)
(yytnamerr, yysyntax_error, yyparse): Prefer ptrdiff_t to size_t.
(YYPTRDIFF_T, YYPTRDIFF_MAXIMUM): New macros.
(YYSIZE_T): Fix "! defined YYSIZE_T" typo.
(YYSIZE_MAXIMUM): Take the minimum of PTRDIFF_MAX and SIZE_MAX.
(YYSIZEOF): New macro.
(YYSTACK_GAP_MAXIMUM, YYSTACK_BYTES, YYSTACK_RELOCATE)
(yy_lac_stack_realloc, yyparse): Use it.
(YYCOPY, yy_lac_stack_realloc): Cast to YYSIZE_T to pacify GCC.
(yy_reduce_print): Use int instead of unsigned long when int
will do.
(yy_lac_stack_realloc): Prefer long to unsigned long when
either will do.
* tests/regression.at: Adjust to these changes.
Instead of
#define YYPACT_NINF -130
#define yypact_value_is_default(Yystate) \
(!!((Yystate) == (-130)))
generate
#define YYPACT_NINF (-130)
#define yypact_value_is_default(Yyn) \
((Yyn) == YYPACT_NINF)
* data/skeletons/c.m4 (b4_table_value_equals): Add support for $4.
* data/skeletons/glr.c, data/skeletons/yacc.c: Use it.
Also, use shorter macro argument names, the name of the macro is clear
enough.
This makes reading the trace slightly easier. It would be very nice
to highlight the "big steps", especially reductions. But this is a
private experiment: do not use it.
* data/diagnostics.css (value): New.
* src/parse-gram.y: Use no delimiters and no c quotation for strings
to facilitate debugging.
(tron, troff, TRACE): New.
Not very elegant, but until there is support for printf-formats in
libtextstyle, it shall be enough.
Reported by Balázs Scheidler.
* data/skeletons/c.m4 (b4_location_type_define): Use api.location.type
if defined.
* doc/bison.texi: Document it.
* tests/local.at (AT_C_IF, AT_LANG_CASE): New.
Support Span in C.
* tests/calc.at (Span): Convert it to be usable in C and C++.
Check api.location.type with yacc.c and glr.c.
Currently, with --no-lines, instead of "#line file line\n", we emit
"\n". Let's emit nothing.
* data/skeletons/bison.m4 (b4_syncline): Emit at end-of-line when enabled.
* data/skeletons/bison.m4, data/skeletons/c.m4, data/skeletons/glr.cc,
* data/skeletons/lalr1.cc, src/output.c: Use dnl after b4_syncline to
avoid spurious empty lines.
* tests/synclines.at (Sync Lines): Make sure that --no-lines is like
grep -v #line.
* tests/calc.at: Make sure that a rich grammar file behaves properly
with %no-lines.
The timevar and bitset modules now use the c99 module which causes
$CXX to now include -std=gnu++11 when possible. Unfortunately, G++
4.7 does not implement [[noreturn]] in C++11 mode, so our tests of
glr.cc (which uses _Noreturn) fail with
input.cc:954:1: error: expected unqualified-id before '[' token
right before [[noreturn]]. 4.8 works fine.
* data/skeletons/c.m4 (b4_attribute_define): Do not use [[noreturn]]
with GCC 4.7.
