* maint:
c++: shorten the assertions that check whether tokens are correct
c++: don't glue functions together
lalr1.cc: YY_ASSERT should use api.prefix
c++: don't use YY_ASSERT at all if parse.assert is disabled
c++: style: follow the Bison m4 quoting pattern
yacc.c: provide the Bison version as an integral macro
regen
style: make conversion of version string to int public
%require: accept version numbers with three parts ("3.7.4")
yacc.c: fix #definition of YYEMPTY
gnulib: update
doc: fix incorrect section title
doc: minor grammar fixes in counterexamples section
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).
The name "defines" is incorrect, the generated file contains far more
than just #defines.
* src/getargs.h, src/getargs.c (-H, --header): New option.
With optional argument, just like --defines, --xml, etc.
(defines_flag): Rename as...
(header_flag): this.
Adjust dependencies.
* data/skeletons/bison.m4, data/skeletons/c.m4, data/skeletons/glr.c,
* data/skeletons/glr.cc, data/skeletons/glr2.cc, data/skeletons/lalr1.cc,
* data/skeletons/yacc.c:
Adjust.
* examples, doc/bison.texi: Adjust.
* tests/headers.at, tests/local.at, tests/output.at: Convert most
tests from using --defines to using --header.
We will not keep YYERRCODE anyway, it causes backward compatibility
issues. So as a first step, let all the skeletons use that name,
until we have a better one.
* data/skeletons/bison.m4, data/skeletons/glr.c,
* data/skeletons/glr.cc, data/skeletons/lalr1.cc,
* data/skeletons/lalr1.d, data/skeletons/lalr1.java,
* data/skeletons/yacc.c, doc/bison.texi, tests/headers.at,
* tests/input.at:
here.
A forthcoming commit (tokens: properly define the "error" token kind)
revealed a problem in the C++ generated headers: they are not
self-contained. With this file:
%language "c++"
%define api.value.type variant
%code {
static int yylex (yy::parser::semantic_type *lvalp);
}
%token <int> X
%%
exp:
X { printf ("x\n"); }
;
%%
void
yy::parser::error (const std::string& m)
{
std::cerr << m << '\n';
}
static
int yylex (yy::parser::semantic_type *lvalp)
{
static int const input[] = {yy::parser::token::X, 0};
static int toknum = 0;
return input[toknum++];
}
int
main (int argc, char const* argv[])
{
yy::parser p;
return p.parse ();
}
the generated header fails to compile cleanly (foo.cc just #includes
the generated header):
$ clang++-mp-9.0 -c -Wundefined-func-template foo.cc
In file included from foo.cc:1:
bar.tab.hh:550:12: warning: instantiation of function 'yy::parser::basic_symbol<yy::parser::by_type>::basic_symbol' required here, but no definition is available
[-Wundefined-func-template]
struct symbol_type : basic_symbol<by_type>
^
bar.tab.hh:436:7: note: forward declaration of template entity is here
basic_symbol (basic_symbol&& that);
^
bar.tab.hh:550:12: note: add an explicit instantiation declaration to suppress this warning if 'yy::parser::basic_symbol<yy::parser::by_type>::basic_symbol' is explicitly instantiated
in another translation unit
struct symbol_type : basic_symbol<by_type>
^
1 warning generated.
* data/skeletons/c++.m4 (b4_public_types_define): Move the
implementation of the basic_symbol move-ctor to...
(b4_public_types_define): here, its declaration.
* tests/headers.at (Sane headers): Use a declared token so that the
corresponding token constructor is declared. Which triggers the
aforementioned issue.
Because of the insane current implementation of glr.cc, things are a
bit nasty. We will rename symbol_number_type as symbol_type_type
later, to keep this commit small.
* data/skeletons/c++.m4 (b4_declare_symbol_enum): New.
Also define YYNTOKENS to avoid type clashes when yyntokens_ was
actually defined in another enum.
Use it.
(symbol_number_type): Be an alias of symbol_type_type.
Use YYSYMBOL_YYEMPTY and the like.
Use symbol_number_type where appropriate.
(empty_symbol): Remove.
(yytranslate_): Use symbol_number_type, not token_number_type.
* data/skeletons/lalr1.cc: Use symbol_number_type where appropriate.
Adjust to the replacement of empty_symbol by YYSYMBOL_YYEMPTY.
(yy_error_token_, yy_undef_token_, yyeof_, yyntokens_): Remove.
Adjust dependencies.
* data/skeletons/glr.cc: Use symbol_number_type where appropriate.
Forward definitions of YYSYMBOL_YYEMPTY, etc. to glr.c.
* tests/headers.at: Accept YYNTOKENS and other YYSYMBOL_*.
* tests/local.at (AT_YYERROR_DEFINE(c++)): Use symbol_number_type.
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.
This is really weird: GCC points to the LHS of the assignment...
260. headers.at:184: testing Sane headers: api.pure api.push-pull=both ...
tests/headers.at:184: COLUMNS=1000; export COLUMNS; bison --color=no -fno-caret -d -o input.c input.y
tests/headers.at:184: $CC $CFLAGS $CPPFLAGS -c -o input.o input.c
stderr:
input.c: In function 'yyparse':
input.c:1276:16: error: 'yylval' may be used uninitialized in this function [-Werror=maybe-uninitialized]
1276 | yylval = *yypushed_val;
| ~~~~~~~^~~~~~~~~~~~~~~
input.c: In function 'yypull_parse':
input.c:1276:16: error: 'yylval' may be used uninitialized in this function [-Werror=maybe-uninitialized]
1276 | yylval = *yypushed_val;
| ~~~~~~~^~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
stdout:
tests/headers.at:184: exit code was 1, expected 0
See also d87c8ac79a
and 9645a2b20e.
* tests/headers.at (Several parsers, Several parsers): Disable these
warnings when in push parser.
Sun C 5.12 defines __SUNPRO_C to 0x5120 but diagnoses
‘__attribute__ ((__unused__))’. Change the ifdefs to use
the same method as Gnulib in this area.
* data/skeletons/c.m4 (YY_ATTRIBUTE): Remove, since
not all attributes were added in the same compiler version.
(YY_ATTRIBUTE_PURE, YY_ATTRIBUTE_UNUSED):
Use specific GCC version for each attribute.
Pay no attention to __SUNPRO_C.
* tests/headers.at (Several parsers): Tighten tests accordingly.
Let's make a difference between places where Perl is required for the
test (AT_PERL_REQUIRE), and the places where it's used to run the
test, but it's not not to run the test (AT_PERL_CHECK).
* tests/local.at (AT_REQUIRE): New.
(AT_PERL_CHECK, AT_PERL_REQUIRE): New.
Use them where appropriate.
* tests/local.mk ($(TESTSUITE)): Beware not to start the line with
'-pi' if Perl is empty, as Make understands this as "it's ok to fail".
Which it is not.
My previous tests (with ./configure PERL=false) have been fooled by
configure, that managed to find perl anyway. This time, I ran this on
a Fedora in Docker, without Perl.
* tests/calc.at, tests/diagnostics.at, tests/headers.at,
* tests/input.at, tests/local.at, tests/named-refs.at,
* tests/output.at, tests/regression.at, tests/skeletons.at,
* tests/synclines.at, tests/torture.at: Don't require Perl.
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 the caller must specify the ./ prefix to its command. Let's
avoid that: it will be nicer to read, make it easier to have a version
that works for Java and C/C++.
* tests/local.at (AT_PARSER_CHECK): Prefix the command with ./.
Adjust callers.
Reported by Derek Clegg
http://lists.gnu.org/archive/html/bug-bison/2019-01/msg00021.html
aux/parser-internal.h:429:12: error: 'syntax_error' has no out-of-line virtual
method definitions; its vtable will be emitted in every translation unit
[-Werror,-Wweak-vtables]
struct syntax_error : std::runtime_error
To avoid this warning, we need syntax_error to have a virtual function
defined in a compilation unit. Let it be the destructor. To comply
with C++98, this dtor should be 'throw()'. Merely making YY_NOEXCEPT
be 'throw()' in C++98 triggers
errors (http://lists.gnu.org/archive/html/bug-bison/2019-01/msg00022.html),
so let's introduce YY_NOTHROW and flag only ~syntax_error with it.
Also, since we now have an explicit dtor, we need to provide an copy
ctor.
* configure.ac (warn_cxx): Add -Wweak-vtables.
* data/skeletons/c++.m4 (YY_NOTHROW): New.
(syntax_error): Declare the dtor, and define the copy ctor.
* data/skeletons/glr.cc, data/skeletons/lalr1.cc (~syntax_error):
Define.
* src/fixits.h, src/fixits.c (fixits_empty): New.
* src/complain.c (deprecated_directive): Register the Wdeprecated
fixits only if -Wdeprecated was enabled, so that we don't apply
updates if the user didn't ask for them.
* src/main.c (main): If there were fixits, issue a warning suggesting
running with --update.
Free uniqstrs after the fixits, since the latter use the former.
* tests/headers.at, tests/input.at: Update expectations.
Reported by Derek Clegg.
http://lists.gnu.org/archive/html/bug-bison/2019-01/msg00006.html
Clang does not like this:
template <typename D>
struct basic_symbol : D
{
basic_symbol();
};
struct by_type {};
struct symbol_type : basic_symbol<by_type>
{
symbol_type(){}
};
It gives:
$ clang++-mp-7.0 -Wundefined-func-template foo.cc -c
foo.cc:11:3: warning: instantiation of function 'basic_symbol<by_type>::basic_symbol'
required here, but no definition is available [-Wundefined-func-template]
symbol_type(){}
^
foo.cc:4:3: note: forward declaration of template entity is here
basic_symbol();
^
foo.cc:11:3: note: add an explicit instantiation declaration to suppress this warning
if 'basic_symbol<by_type>::basic_symbol' is explicitly instantiated in
another translation unit
symbol_type(){}
^
1 warning generated.
The same applies for the basic_symbol's destructor and `clear()`.
* configure.ac (warn_cxx): Add -Wundefined-func-template.
This triggered one failure in the test suite:
* tests/headers.at (Sane headers): here, where we check that we can
compile the generated headers in other compilation units than the
parser's.
Add a variant type to make sure that basic_symbol and symbol_type are
properly generated in this case.
* data/skeletons/c++.m4 (basic_symbol): Inline the definitions of the
destructor and of `clear` in the class definition.
Currently the diagnostics for %name-prefix are not precise enough. In
particular, they does not show that braces must be used instead of
quotes.
Before:
foo.y:3.1-14: warning: deprecated directive, use '%define api.prefix' [-Wdeprecated]
%name-prefix = "foo"
^^^^^^^^^^^^^^
After:
foo.y:3.1-20: warning: deprecated directive, use '%define api.prefix {foo}' [-Wdeprecated]
%name-prefix = "foo"
^^^^^^^^^^^^^^^^^^^^
To do this we need the value passed to %name-prefix, so move the
warning from the scanner to the parser.
Accuracy will be very important for the forthcoming changes.
* src/parse-gram.y (do_name_prefix): New.
(PERCENT_NAME_PREFIX): Have a semantic value: the raw source, with
possibly underscores, equal sign, and spaces. This is used to provide
a more accurate message. It does not take comments into account,
but...
* src/scan-gram.l (%name-prefix): Delegate the warnings to the parser.
* tests/headers.at, tests/input.at: Adjust expectations.
* tests/local.at (AT_LOCATION_TYPE_IF): Turn into...
(AT_LOCATION_TYPE_SPAN_IF): this.
Adjust dependencies.
* tests/headers.at (Several parsers): Add another C++ parser,
which uses the first C++ parser's locations.
Modern C++ (i.e., C++11 and later) introduced "move only" types: types such
as std::unique_ptr<T> that can never be duplicated. They must never be
copied (by assignments and constructors), they must be "moved". The
implementation of lalr1.cc used to copy symbols (including their semantic
values). This commit ensures that values are only moved in modern C++, yet
remain compatible with C++98/C++03.
Suggested by Frank Heckenbach, who provided a full implementation on
top of C++17's std::variant.
See http://lists.gnu.org/archive/html/bug-bison/2018-03/msg00002.html,
and https://lists.gnu.org/archive/html/bison-patches/2018-04/msg00002.html.
Symbols (terminal/non terminal) are handled by several functions that used
to take const-refs, which resulted eventually in a copy pushed on the stack.
With modern C++ (C++11 and later) the callers must use std::move, and the
callees must take their arguments as rvalue refs (foo&&). In order to avoid
duplicating these functions to support both legacy C++ and modern C++, let's
introduce macros (YY_MOVE, YY_RVREF, etc.) that rely on copy-semantics for
C++98/03, and move-semantics for modern C++.
That's easy for inner types, when the parser's functions pass arguments to
each other. Functions facing the user (make_NUMBER, make_STRING, etc.)
should support both rvalue-refs (for instance to support move-only types:
make_INT (std::make_unique<int> (1))), and lvalue-refs (so that we can pass
a variable: make_INT (my_int)). To avoid the multiplication of the
signatures (there is also the location), let's take the argument by value.
See:
https://lists.gnu.org/archive/html/bison-patches/2018-09/msg00024.html.
* data/c++.m4 (b4_cxx_portability): New.
(basic_symbol): In C++11, replace copy-ctors with move-ctors.
In C++11, replace copies with moves.
* data/lalr1.cc (stack_symbol_type, yypush_): Likewise.
Use YY_MOVE to avoid useless copies.
* data/variant.hh (variant): Support move-semantics.
(make_SYMBOL): In C++11, in order to support both read-only lvalues,
and rvalues, take the argument as a copy.
* data/stack.hh (yypush_): Use rvalue-refs in C++11.
* tests/c++.at: Use move semantics.
* tests/headers.at: Adjust to the new macros (YY_MOVE, etc.).
* configure.ac (CXX98_CXXFLAGS, CXX11_CXXFLAGS, CXX14_CXXFLAGS)
(CXX17_CXXFLAGS, ENABLE_CXX11): New.
* tests/atlocal.in: Receive them.
* examples/variant.yy: Don't define things in std.
* examples/variant-11.test, examples/variant-11.yy: New.
Check the support of move-only types.
* examples/README, examples/local.mk: Adjust.
With GCC7 we have warnings (false positive):
x8.c: In function 'x8_parse':
x8.c:1233:16: error: 'yylval' may be used uninitialized in this function [-Werror=maybe-uninitialized]
yylval = *yypushed_val;
~~~~~~~^~~~~~~~~~~~~~~
x8.c: In function 'x8_pull_parse':
x8.c:1233:16: error: 'yylval' may be used uninitialized in this function [-Werror=maybe-uninitialized]
yylval = *yypushed_val;
~~~~~~~^~~~~~~~~~~~~~~
See also 9645a2b20e.
* tests/local.at (AT_PUSH_IF): New.
(AT_BISON_OPTION_POPDEFS): Pop it, and pop AT_PURE_IF.
* tests/headers.at (Several parsers, Several parsers): Disable these
warnings when in push parser.
The header generated for variants with assertions but without
locations, is not self-contained. Prepare a check for this.
* tests/headers.at (Sane headers): New, extracted from...
(Several parsers): here.
* data/lalr1.cc, doc/bison.texi, etc/bench.pl.in, examples/variant.yy,
* tests/actions.at, tests/atlocal.in, tests/c++.at, tests/headers.at,
* tests/local.at, tests/types.at:
Don't use std::endl, it flushes uselessly, and is considered bad
style.
Building C++ parsers with -Wsuggest-attribute=const and
-Wsuggest-attribute=noreturn triggers warning in generated code.
* data/lalr1.cc: Call b4_attribute_define.
(debug_stream, debug_level): Flag as pure.
* tests/headers.at (Several parsers): There are now more YY macros
that "leak".
* tests/local.at (AT_NAME_PREFIX): Also match api.namespace.
(AT_MAIN_DEFINE): Take it into account.
* tests/c++.at, tests/headers.at: Use AT_NAME_PREFIX.
(AT_CHECK_NAMESPACE): Rename as...
(AT_TEST): this.
Reported by Théophile Ranquet.
* tests/glr-regression.at: Rewrite some test cases so that AT_PARSER_CHECK,
which runs valgrind, is exposed with the parser, not with "echo".
* tests/local.at, tests/regression.at, tests/headers.at:
Use AT_PARSER_CHECK for generated parsers.
Does not work on Solaris 10. Reported by Dennis Clarke.
http://lists.gnu.org/archive/html/bug-bison/2012-11/msg00009.html
* tests/headers.at (Several parsers): Use Perl instead.
While at it, run it only once, on all the generated headers.
Adjust to YY_NULL be defined in position.hh.
