Most often yynerrs is not used. Clang 15 now complains about such
variables. Bison itself does not compile:
```
src/parse-gram.c:1797:9: error: variable 'gram_nerrs' set but not used [-Werror,-Wunused-but-set-variable]
int yynerrs = 0;
^
src/parse-gram.c:79:25: note: expanded from macro 'yynerrs'
^
1 error generated.
```
Reported by Nikita Popov.
Fixes https://github.com/akimd/bison/issues/89.
* data/skeletons/yacc.c (yynerrs): Flag with YY_ATTRIBUTE_UNUSED.
* data/skeletons/lalr1.cc (yynerrs_): Likewise.
Currently we are using pointers. The whole point of
glr2.cc (vs. glr.cc) is precisely to allow genuine C++ objects to be
semantic values. Let's make that work.
* data/skeletons/glr2.cc (glr_state::glr_state): Be sure to initialize
yysval.
(glr_state): Add copy-ctor, assignment and dtor.
(glr_state::copyFrom): Be sure to initialize the destination if it was
not.
(glr_state::~glr_state): Destroy the semantic value.
* examples/c++/glr/ast.hh: Rewrite so that we use genuine objects,
rather than a traditional OOP hierarchy that requires to deal with
pointers.
With help from Bruno Belanyi <bruno.belanyi@epita.fr>.
* examples/c++/glr/c++-types.yy: Remove memory management.
Use true objects.
(main): Don't reach yydebug directly.
* examples/c++/glr/local.mk: We need C++11.
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.
Reported by Martin Blais and Yuriy Solodkyy.
https://lists.gnu.org/r/help-bison/2020-05/msg00011.htmlhttps://lists.gnu.org/r/bug-bison/2020-06/msg00038.html
While at it, modernize filename_type as api.filename.type and document
it properly.
* data/skeletons/c++.m4 (filename_type): Rename as...
(api.filename.type): this.
Default to const std::string.
* data/skeletons/location.cc (position, location): Expose the
filename_type type.
Use api.filename.type.
* doc/bison.texi (%define Summary): Document api.filename.type.
(C++ Location Values): Document position::filename_type.
* src/muscle-tab.c (muscle_percent_variable_update): Ensure backward
compatibility.
* tests/c++.at: Check that using const file names is ok.
tests/input.at: Check backward compat.
Reported by Dwight Guth.
https://lists.gnu.org/r/bug-bison/2020-06/msg00037.html
* src/AnnotationList.c (AnnotationList__computePredecessorAnnotations):
Beware that SBITSET__FOR_EACH nests _two_ for-loops, so "break" does
not actually break out of it.
That was the only occurrence in the code.
* src/Sbitset.h (SBITSET__FOR_EACH): Warn passersby.
pstate_clear is lacking a prototype.
Reported by Ryan
https://lists.gnu.org/r/bug-bison/2020-05/msg00101.html
Besides, none of the C examples were compiled with the warning flags.
* configure.ac (warn_c): Add -Wmissing-prototypes.
* data/skeletons/yacc.c (pstate_clear): Make it static.
* examples/local.mk (TEST_CFLAGS): New.
* examples/c/bistromathic/local.mk, examples/c/calc/local.mk,
* examples/c/lexcalc/local.mk, examples/c/mfcalc/local.mk,
* examples/c/pushcalc/local.mk, examples/c/reccalc/local.mk,
* examples/c/rpcalc/local.mk:
Use it.
GCC's warn_unused_result is not silenced by a cast to void, so we have
to "use" scanf's result.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=25509https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66425
Flex generated code produces too many warnings, including things such
as, with ICC:
examples/c/lexcalc/scan.c(1088): error #1682: implicit conversion
of a 64-bit integral type to a smaller integral type (potential portability problem)
2259 YY_INPUT( (&YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[number_to_move]),
2260 ^
2261
2262
I am tired of trying to fix Flex's output. The project does not seem
maintained. We ought to avoid it. So, for the time being, don't try
to enable warnings with Flex.
* examples/c/bistromathic/parse.y, examples/c/reccalc/scan.l: Fix
warnings.
* doc/bison.texi: Discard scanf's return value to defeat
-Werror=unused-result.
To write unit tests for their scanners, some users depended on
symbol_type::token():
Lexer lex("12345");
symbol_type t = lex.nextToken();
assert(t.token() == token::INTLIT);
assert(t.value.as<int>() == 12345);
But symbol_type::token() was removed in Bison 3.5 because it relied on
a conversion table. So users had to find other patterns, such as
assert(t.type_get() == by_type(token::INTLIT).type_get());
which relies on several private implementation details.
As part of transitioning from "token type" to "token kind", and making
this a public and documented interface, "by_type" was renamed
"by_kind" and "type_get()" was renamed as "kind()". The latter had
backward compatibility mechanisms, not the former.
In Bison 3.6 none of this should be used, but rather
assert(t.kind() == symbol_kind::S_INTLIT);
Reported by Pramod Kumbhar.
https://lists.gnu.org/r/bug-bison/2020-05/msg00012.html
* data/skeletons/c++.m4 (by_type): Make it an alias to by_kind.
* maint:
maint: post-release administrivia
version 3.5.4
examples: reccalc: really compile cleanly in C99
news: announce that Bison 3.6 drops YYERROR_VERBOSE
news: update for 3.5.4
style: fix spellos
typo: succesful -> successful
package: improve the readme
java: check and fix support for api.token.raw
java: style: prefer 'int[] foo' to 'int foo[]'
build: fix syntax-check issues
tests: recheck: work properly when the test suite was interrupted
doc: c++: promote api.token.raw
build: fix compatibility with old compilers
examples: reccalc: compile cleanly in C99
GCC 4.2 dies with
src/InadequacyList.c: In function 'InadequacyList__new_conflict':
src/InadequacyList.c:37: error: #pragma GCC diagnostic not allowed inside functions
src/InadequacyList.c:37: error: #pragma GCC diagnostic not allowed inside functions
src/InadequacyList.c:40: error: #pragma GCC diagnostic not allowed inside functions
Reported by Evan Lavelle.
See https://lists.gnu.org/r/bug-bison/2020-03/msg00021.html
and https://trac.macports.org/ticket/59927.
* src/system.h (GCC_VERSION): New.
Use it to control IGNORE_TYPE_LIMITS_BEGIN and
IGNORE_TYPE_LIMITS_END.
Suggested by Adrian Vogelsgesang.
https://lists.gnu.org/archive/html/bison-patches/2020-02/msg00069.html
* data/skeletons/lalr1.java (Context.EMPTY, Context.getToken): New.
(Context.yyntokens): Rename as...
(Context.NTOKENS): this.
Because (i) all the Java coding styles recommend upper case for
constants, and (ii) the Java Skeleton exposes Lexer.EOF, not
Lexer.YYEOF.
* data/skeletons/yacc.c (yyparse_context_token): New.
* examples/c/bistromathic/parse.y (yyreport_syntax_error): Don't use
yysyntax_error_arguments.
* examples/java/calc/Calc.y (yyreportSyntaxError): Likewise.
Because we want to support $<a->b>$, we must accept -> in type tags,
and reject $<->$, as it is unfinished.
Reported by Ahcheong Lee.
* src/scan-code.l (yylex): Make sure "tag" does not end with -, since
-> does not close the tag.
* tests/input.at (Stray $ or @): Check this.
See https://github.com/nemequ/icc-travis/issues/15.
Thanks to Jeff Hammond and Evan Nemerson for their help.
* configure.ac (warn_common): Disable dubious warnings.
* .travis.yml: Use ICC again.
Having a file named "exception" is risky: the compiler might use that
file in #include.
Reported by 马俊 <majun123@whu.edu.cn>.
* tests/local.at (AT_SKIP_IF_EXCEPTION_SUPPORT_IS_POOR): Generate
'exceptions', not 'exception'.
Reported by Thomas Petazzoni.
https://lists.gnu.org/archive/html/bug-bison/2019-08/msg00000.html
* examples/c/reccalc/local.mk: Complete dependencies, including for
earlier versions of Automake (for sake of our CI, on top of Ubuntu
Xenial/Bionic, which feature only Automake 1.15).
(%D%/scan.c %D%/scan.h): Upgrade to the full version provided in
Automake's documentation.
Currently we properly use the "best" integral type for tables,
including those storing state numbers. However the variables for
state numbers used in yyparse (and its dependencies such as
yy_stack_print) still use int16_t invariably. As a consequence, very
large models overflow these variables.
Let's use the "best" type for these variables too. It turns out that
we can still use 16 bits for twice larger automata: stick to unsigned
types.
However using 'unsigned' when 16 bits are not enough is troublesome
and generates tons of warnings about signedness issues. Instead,
let's use 'int'.
Reported by Tom Kramer.
https://lists.gnu.org/archive/html/bug-bison/2019-09/msg00018.html
* data/skeletons/yacc.c (b4_state_num_type): New.
(yy_state_num): Be computed from YYNSTATES.
* tests/linear: New.
* tests/torture.at (State number type): New.
Use it.
Reported by Andreas Damm.
https://savannah.gnu.org/support/?110032
* data/skeletons/lalr1.cc (stack_symbol_type::operator=): New
overload, const, to please the IAR C++ compiler (version ca 2013).
With
%token EOF 0 EOF 0
we get
input.y:3.14-16: warning: symbol EOF redeclared [-Wother]
3 | %token EOF 0 EOF 0
| ^~~
input.y:3.8-10: previous declaration
3 | %token EOF 0 EOF 0
| ^~~
Assertion failed: (nsyms == ntokens + nvars), function check_and_convert_grammar,
file /Users/akim/src/gnu/bison/src/reader.c, line 839.
Reported by Marc Schönefeld.
* src/symtab.c (symbol_user_token_number_set): Register only the
first definition of the end of input token.
* tests/input.at (Symbol redeclared): Check that case.
hash_initialize returns NULL when out of memory. Check for it, and
die cleanly instead of crashing.
Reported by 江 祖铭 (Zu-Ming Jiang).
https://lists.gnu.org/archive/html/bug-bison/2019-08/msg00015.html
* src/muscle-tab.c, src/state.c, src/symtab.c, src/uniqstr.c:
Check the value returned by hash_initialize.
https://lists.gnu.org/archive/html/bison-patches/2019-08/msg00007.html
When Bison is started with a flag that suppresses warning messages, the
error_message() function can produce a few gigabytes of indentation
because of a dangling pointer.
* src/complain.c (error_message): Don't reset indent_ptr here, but...
(complain_indent): here.
* tests/diagnostics.at (Indentation with message suppression): Check
this case.
Build the tarball in one job, check it in many.
Unfortunately no real gain in overall duration.
With help from Clément Démoulins.
* .travis.yml: here.
Remove all the tricks that were used to be able to boostrap on old
distros.
(before_install): Merge into 'script', because before_install applies
to all the jobs, and we don't want to run it for the 'compile' job.
The "includes" relation [DeRemer 1982] is between gotos, so of course,
for a given goto, there cannot be more that ngotos (number of gotos)
images. But we manipulate the set of images of a goto as a list,
without checking that an image was not already introduced. So we can
"register" way more images than ngotos, leading to a crash (heap
buffer overflow).
Reported by wcventure.
http://lists.gnu.org/archive/html/bug-bison/2019-03/msg00007.html
For the records, this bug is present in the first committed version of
Bison.
* src/lalr.c (build_relations): Don't insert the same goto several
times.
* tests/sets.at (Build Relations): New.
Since Bison 3.3, semantic values in rule actions (i.e., '$...') are
passed to the m4 backend as the symbol number. Unfortunately, when
there are unused symbols, the symbols are renumbered _after_ the
numbers were used in the rule actions. As a result, the evaluation of
the skeleton failed because it used non existing symbol numbers.
Which is the happy scenario: we could use numbers of other existing
symbols...
Reported by Balázs Scheidler.
http://lists.gnu.org/archive/html/bug-bison/2019-01/msg00044.html
Translating the rule actions after the symbol renumbering moves too
many parts in bison. Relying on the symbol identifiers is more
troublesome than it might first seem: some don't have an
identifier (tokens with only a literal string), some might have a
complex one (tokens with a literal string with characters special for
M4). Well, these are tokens, but nterms also have issues: "dummy"
nterms (for midrule actions) are named $@32 etc. which is risky for
M4.
Instead, let's simply give M4 the mapping between the old numbers and
the new ones. To avoid confusion between old and new numbers, always
emit pre-renumbering numbers as "orig NUM".
* data/README: Give details about "orig NUM".
* data/skeletons/bison.m4 (__b4_symbol, _b4_symbol): Resolve the
"orig NUM".
* src/output.c (prepare_symbol_definitions): Pass nterm_map to m4.
* src/reduce.h, src/reduce.c (nterm_map): Extract it from
nonterminals_reduce, to make it public.
(reduce_free): Free it.
* src/scan-code.l (handle_action_dollar): When referring to a nterm,
use "orig NUM".
* tests/reduce.at (Useless Parts): New, based Balázs Scheidler's
report.
Suggested by David Barto
https://lists.gnu.org/archive/html/help-bison/2015-02/msg00004.html
and Victor Zverovich.
https://lists.gnu.org/archive/html/bison-patches/2018-10/msg00121.html
This is very easy to do, thanks to work by Bruno Haible in gnulib.
See "Supporting Relocation" in gnulib's documentation.
* bootstrap.conf: We need relocatable-prog and relocatable-script (for yacc).
* src/yacc.in: New.
* configure.ac, src/local.mk: Instantiate it.
* src/main.c, src/output.c (main, pkgdatadir): Use relocatable2.
* doc/bison.texi (FAQ): Document it.
