On the CI, we have this spurious failure with clang 3.9 with
-std=c++17:
In file included from list.y:23:
In file included from /usr/include/c++/4.8/iostream:39:
In file included from /usr/include/c++/4.8/ostream:38:
In file included from /usr/include/c++/4.8/ios:42:
In file included from /usr/include/c++/4.8/bits/ios_base.h:41:
In file included from /usr/include/c++/4.8/bits/locale_classes.h:40:
In file included from /usr/include/c++/4.8/string:52:
In file included from /usr/include/c++/4.8/bits/basic_string.h:2815:
In file included from /usr/include/c++/4.8/ext/string_conversions.h:43:
/usr/include/c++/4.8/cstdio:120:11: error: no member named 'gets' in the global namespace
using ::gets;
~~^
This shows that our test, based on gl_WARN_ADD, is a joke. We have to
really check for at least a bit of C++.
* m4/ax_check_compile_flag.m4, m4/bison-cxx-std.m4: New.
* configure.ac: Use them to make sure the compiler actually works.
In C++ pre C++11 it is standard practice to use 0 for the null pointer.
But GCC pre 8 -std=c++98 with -Wzero-as-null-pointer-constant warns about
this.
So disable -Wzero-as-null-pointer-constant when compiling C++ pre 11.
Let's do this in AT_DATA_SOURCE_PROLOGUE (which is pasted on top of
all the test grammar files). Unfortunately, that shifts all the
locations in the expected error messages, which would be too noisy.
Instead, let's introduce testsuite.h, which can vary in length, and
include it in AT_DATA_SOURCE_PROLOGUE.
* tests/testsuite.h: New.
Disable -Wzero-as-null-pointer-constant's warning with GCC pre 8,
C++ pre 11.
* tests/local.at (AT_DATA_SOURCE_PROLOGUE): Use it.
* tests/atlocal.in (CPPFLAGS): Find it.
* tests/local.mk: Ship it.
* data/c.m4 (YY_NULLPTR): Prefer ((void*)0) to 0 in C.
This is much of course more efficient than in the matrix of the CI (or
on our own machines), but a bit more tedious.
* configure.ac (CXX03_CXXFLAGS, CXX11_CXXFLAGS, CXX14_CXXFLAGS)
(CXX17_CXXFLAGS, CXX2A_CXXFLAGS, STDCXX_FLAGS): New.
* tests/atlocal.in: Receive them.
* tests/local.at (AT_FOR_EACH_CXX): New.
* tests/c++.at: Use AT_FOR_EACH_CXX.
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.
Most of our variables for C++ flags are named FOO_CXXFLAGS, not
CXXFLAGS_FOO.
* configure.ac, tests/atlocal.in, tests/calc.at
(NO_EXCEPTIONS_CXXFLAGS): Rename as...
(CXXFLAGS_NO_EXCEPTIONS): this.
Clang++ issues warnings when it's used to compile C. This make target
is precisely checking whether we can do that.
* configure.ac (NO_DEPRECATED_CXXFLAGS): New.
* tests/atlocal.in: Use it.
Reported by Brooks Moses <bmoses@google.com>
http://lists.gnu.org/archive/html/bison-patches/2018-02/msg00000.html
* data/lalr1.cc (YY_EXCEPTIONS): New.
Use it to disable try/catch clauses.
* doc/bison.texi (C++ Parser Interface): Document it.
* configure.ac (CXXFLAGS_NO_EXCEPTIONS): New.
* tests/atlocal.in: Receive it.
* tests/local.at (AT_FULL_COMPILE, AT_LANG_COMPILE):
Accept a new argument, extra compiler flags.
* tests/calc.at: Run the C++ calculator with exception support disabled.
* 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.
There are possible conflicts between gnulib replacement functions (in
<stdio.h>) and their C++ wrappers (in <stream>). Trying to address
these in configure seems too hard, and I don't know how to fix the issue
in gnulib. Cowardly avoid the problem by skipping C++ tests when this
happens.
Reported by Stefano Lattarini.
http://lists.gnu.org/archive/html/bug-bison/2013-06/msg00001.html
* tests/atlocal.in (BISON_CXX_WORKS): Also set it to "skip" if we can't
compile a simple program using <stream>.
* tests/local.at: Comment changes.
This is based on what is recommended by both Scott Meyers, in 'Effective
C++', and Andrei Alexandrescu and Herb Sutter in 'C++ Coding Standards'.
Use a static_cast on void* rather than directly use a reinterpret_cast,
which can have nefarious effects on objects. However, even though following
this guideline is good practice in general, I am not quite sure how relevant
it is when applied to conversions from POD to objects. Actually, it might
very well be the opposite: isn't this exactly what reinterpret_cast is for?
What we really want *is* to transmit the memory map as a series of bytes,
which, if I am correct, falls into the kind of "low level" hack for which
this cast is meant.
In any case, this silences the warning, which will be greatly appreciated by
anyone using variants with a compiler supporting -fstrict-aliasing.
* data/variant.hh (as): Here.
* tests/c++.at (Exception safety, C++ Variant-based Symbols, Variants):
Don't use NO_STRICT_ALIAS_CXXFLAGS (revert commit ddb9db15), as type punning
is no longer an issue.
* tests/atlocal.in, configure.ac (NO_STRICT_ALIAS_CXXFLAGS): Remove
definition.
* examples/local.mk (NO_STRICT_ALIAS_CXXFLAGS): Remove from AM_CXXFLAGS.
* doc/bison.texi: Don't mention type punning issues.
* origin/maint:
news: prepare for forthcoming release
doc: explain how mid-rule actions are translated
error: use better locations for unused midrule values
doc: various minor improvements and fixes
tests: ignore more useless compiler warnings
tests: be robust to C being compiled with a C++11 compiler
build: beware of Clang++ not supporting POSIXLY_CORRECT
maint: post-release administrivia
version 2.6.90
build: fix syntax-check error.
cpp: simplify the Flex version checking macro
news: improve the carets example and fix a typo
cpp: improve the Flex version checking macro
carets: improve the code
maint: update news
build: keep -Wmissing-declarations and -Wmissing-prototypes for modern GCCs
build: drop -Wcast-qual
gnulib: update
Conflicts:
NEWS
doc/Makefile.am
doc/bison.texi
gnulib
src/reader.c
tests/actions.at
tests/atlocal.in
tests/input.at
* m4/c-working.m4 (BISON_LANG_COMPILER_POSIXLY_CORRECT): New.
(BISON_C_COMPILER_POSIXLY_CORRECT): Use it.
For consistency with C++, also define BISON_C_WORKS.
* m4/cxx.m4 (BISON_CXX_COMPILER_POSIXLY_CORRECT): New.
* configure.ac: Use it.
* tests/atlocal.in: Get its result.
Propagate properly CXX values when used to compile C.
When POSIXLY_CORRECT, adjust BISON_C_WORKS and BISON_CXX_WORKS.
* tests/local.at (AT_COMPILE): Use BISON_C_WORKS.
* origin/maint:
regen
maint: post-release administrivia
version 2.6.5
regen
tests: syntax-check
tests: beware of compilers that do not support POSIXLY_CORRECT
gnulib: update
Conflicts:
src/parse-gram.c
src/parse-gram.h
tests/atlocal.in
Running "maintainer-release-check" on OS X with Clang 2.9 fails,
because "clang-mp-2.9 -o test -g test.c" launches "/usr/bin/dsymutil
test -o test.dSYM" which fails with "error: unable to open executable
'-o'".
* m4/c-working.m4 (BISON_CHECK_WITH_POSIXLY_CORRECT)
(BISON_C_COMPILER_POSIXLY_CORRECT): New.
* configure.ac: Use the latter.
* tests/atlocal.in (POSIXLY_CORRECT_IS_EXPORTED): New.
* tests/local.at (AT_BISON_CHECK_WARNINGS_): Use it instead of computing its
value each time.
(AT_QUELL_VALGRIND): Skip tests that cannot work because of compilers
that do not support POSIXLY_CORRECT.
Tests are running without -O since
f377f69fec because some warnings (about
yylval not being initialized) show only when GCC is given -O2. The
previous patch fixes the warnings. Run the test suite with compiler
options unmodified.
* tests/atlocal.in (O0CFLAGS, O0CXXFLAGS): Remove, use CFLAGS and
CXXFLAGS.
Tests are running without -O since
f377f69fec because some warnings (about
yylval not being initialized) show only when GCC is given -O2. The
previous patch fixes the warnings. Run the test suite with compiler
options unmodified.
* tests/atlocal.in (O0CFLAGS, O0CXXFLAGS): Remove, use CFLAGS and
CXXFLAGS.
* origin/maint:
maint: update gnu-web-doc-update.
maint: post-release administrivia
version 2.6
maint: prepare for release 2.6
maint: post-release administrivia
version 2.5.91
maint: prepare NEWS.
maint: fix spaces.
tests: adjust to case where the C compiler is actually a C++ compiler
tests: fix dependencies
doc: fix Texinfo command
maint: Valgrind on OS X.
tests: be sure that backups are safe.
maint: dead comment.
tests: refactor for legibility.
tests: refactor the bison invocations.
maint: fix syntax-check ignore patterns.
gnulib: update
gnulib: update.
gnulib: update
Conflicts:
build-aux/Makefile.am
cfg.mk
tests/Makefile.am
* origin/maint:
tests: headers.at: strengthen.
glr.cc: do not override C++ definitions by C macros.
YYLLOC_DEFAULT: factor, and don't export it in headers.
api.prefix: do not use #define to handle YYSTYPE_IS_TRIVIAL etc.
tests: portability fixes.
c++: fewer #includes in the headers.
glr.cc: formatting changes.
tests: more logs.
api.prefix: also rename YYDEBUG.
Conflicts:
data/c.m4
data/glr.c
data/glr.cc
data/lalr1.cc
data/yacc.c
* origin/maint:
bump to 2012 in skeletons.
build: remove ancient Autoconf tests.
doc: c++: complete the location documentation.
c++: locations: provide convenience constructors.
c++: locations: remove useless "inline".
glr: do not use locations when they are not requested
c++: use nullptr for C++11.
build: simplify and improve the compiler warnings for tests.
gnulib: update.
maint: formatting changes.
NEWS: update.
Java: Fix syntax error handling without error token.
tests: beware of -pedantic on large #line numbers.
tests: when using the C++ compiler, use its flags too.
Conflicts:
data/glr.c
data/glr.cc
data/lalr1.cc
data/location.cc
data/yacc.c
tests/Makefile.am
* configure.ac (warn_common, warn_c, warn_cxx): New.
Use them to compute independently the options supported
by the C and C++ compilers.
Don't AC_SUBST the variables passed to gl_WARN_ADD: it
does it for us.
(WARN_CFLAGS_TEST, WARN_CXXFLAGS_TEST): Don't aggregate
$WARN_CFLAGS and $WARN_CXXFLAGS in them now, leave it
to atlocal.in.
(O0CFLAGS, O0CXXFLAGS): Move their definition to...
* tests/atlocal.in: here.
Be more systematic between C and C++.
Reorder to factor between variables.
Propagate all of the variables when --compile-c-with-cxx.
* tests/local.at: Go for colors.
(--compile-c-with-cxx): New option.
We used to pass "CC=$CXX" as command line argument,
but it was not possible to adjust CFLAGS accordingly
in atlocal, since it is loaded before assignments on
the command line are honored (so that the command line
takes precedence).
* tests/atlocal.in: Implement it.
* tests/local.mk: Use it.
(cherry picked from commit ac3f2e33b4)
Conflicts:
tests/local.mk
* tests/local.at: Go for colors.
(--compile-c-with-cxx): New option.
We used to pass "CC=$CXX" as command line argument,
but it was not possible to adjust CFLAGS accordingly
in atlocal, since it is loaded before assignments on
the command line are honored (so that the command line
takes precedence).
* tests/atlocal.in: Implement it.
* tests/local.mk: Use it.
This change was made by applying emacs' untabify function to
nearly all files in Bison's repository. Required tabs in make
files, ChangeLog, regexps, and test code were manually skipped.
Other notable exceptions and changes are listed below.
* bootstrap: Skip because we sync this with gnulib.
* data/m4sugar/foreach.m4
* data/m4sugar/m4sugar.m4: Skip because we sync these with
Autoconf.
* djgpp: Skip because I don't know how to test djgpp properly, and
this code appears to be unmaintained anyway.
* README-hacking (Hacking): Specify that tabs should be avoided
where not required.
