The use of #pragma GCC system_header in libstdc++ has led to bugs going
undetected for a while due to the silencing of compiler warnings that would
have revealed them promptly, and also interferes with warnings about
problematic template instantiations induced by user code.
But removing it, or even compiling with -Wsystem-header, is also problematic
due to warnings about deliberate uses of extensions.
So this patch adds #pragma GCC diagnostic as needed to suppress these
warnings.
The change to acinclude.m4 changes -Wabi to warn only in comparison to ABI
19, to avoid lots of warnings that we now mangle concept requirements, which
are in any case still experimental. I checked for any other changes against
ABI v15, and found only the <format> lambda mangling, which we can ignore.
This also enables -Wsystem-headers while building the library, so we see any
warnings not silenced by these #pragmas.
libstdc++-v3/ChangeLog:
* include/bits/algorithmfwd.h:
* include/bits/allocator.h:
* include/bits/codecvt.h:
* include/bits/concept_check.h:
* include/bits/cpp_type_traits.h:
* include/bits/hashtable.h:
* include/bits/iterator_concepts.h:
* include/bits/ostream_insert.h:
* include/bits/ranges_base.h:
* include/bits/regex_automaton.h:
* include/bits/std_abs.h:
* include/bits/stl_algo.h:
* include/c_compatibility/fenv.h:
* include/c_compatibility/inttypes.h:
* include/c_compatibility/stdint.h:
* include/ext/concurrence.h:
* include/ext/type_traits.h:
* testsuite/ext/type_traits/add_unsigned_floating_neg.cc:
* testsuite/ext/type_traits/add_unsigned_integer_neg.cc:
* testsuite/ext/type_traits/remove_unsigned_floating_neg.cc:
* testsuite/ext/type_traits/remove_unsigned_integer_neg.cc:
* include/bits/basic_ios.tcc:
* include/bits/basic_string.tcc:
* include/bits/fstream.tcc:
* include/bits/istream.tcc:
* include/bits/locale_classes.tcc:
* include/bits/locale_facets.tcc:
* include/bits/ostream.tcc:
* include/bits/regex_compiler.tcc:
* include/bits/sstream.tcc:
* include/bits/streambuf.tcc:
* configure: Regenerate.
* include/bits/c++config:
* include/c/cassert:
* include/c/cctype:
* include/c/cerrno:
* include/c/cfloat:
* include/c/climits:
* include/c/clocale:
* include/c/cmath:
* include/c/csetjmp:
* include/c/csignal:
* include/c/cstdarg:
* include/c/cstddef:
* include/c/cstdio:
* include/c/cstdlib:
* include/c/cstring:
* include/c/ctime:
* include/c/cwchar:
* include/c/cwctype:
* include/c_global/climits:
* include/c_global/cmath:
* include/c_global/cstddef:
* include/c_global/cstdlib:
* include/decimal/decimal:
* include/ext/rope:
* include/std/any:
* include/std/charconv:
* include/std/complex:
* include/std/coroutine:
* include/std/format:
* include/std/iomanip:
* include/std/limits:
* include/std/numbers:
* include/tr1/functional:
* include/tr1/tuple:
* include/tr1/type_traits:
* libsupc++/compare:
* libsupc++/new: Add #pragma GCC diagnostic to suppress
undesired warnings.
* acinclude.m4: Change -Wabi version from 2 to 19.
gcc/ChangeLog:
* ginclude/stdint-wrap.h: Add #pragma GCC diagnostic to suppress
undesired warnings.
* gsyslimits.h: Likewise.
This implements the C++23 paper P2419R2 (Clarify handling of encodings
in localized formatting of chrono types). The requirement is that when
the literal encoding is "a Unicode encoding form" and the formatting
locale uses a different encoding, any locale-specific strings such as
"août" for std::chrono::August should be converted to the literal
encoding.
Using the recently-added std::locale::encoding() function we can check
the locale's encoding and then use iconv if a conversion is needed.
Because nl_langinfo_l and iconv_open both allocate memory, a naive
implementation would perform multiple allocations and deallocations for
every snippet of locale-specific text that needs to be converted to
UTF-8. To avoid that, a new internal locale::facet is defined to store
the text_encoding and an iconv_t descriptor, which are then cached in
the formatting locale. This requires access to the internals of a
std::locale object in src/c++20/format.cc, so that new file needs to be
compiled with -fno-access-control, as well as -std=gnu++26 in order to
use std::text_encoding.
Because the new std::text_encoding and std::locale::encoding() symbols
are only in the libstdc++exp.a archive, we need to include
src/c++26/text_encoding.cc in the main library, but not export its
symbols yet. This means they can be used by the two new functions which
are exported from the main library.
The encoding conversions are done for C++20, treating it as a DR that
resolves LWG 3656.
With this change we can increase the value of the __cpp_lib_format macro
for C++23. The value should be 202207 for P2419R2, but we already
implement P2510R3 (Formatting pointers) so can use the value 202304.
libstdc++-v3/ChangeLog:
PR libstdc++/109162
* acinclude.m4 (libtool_VERSION): Update to 6:34:0.
* config/abi/pre/gnu.ver: Disambiguate old patters. Add new
GLIBCXX_3.4.34 symbol version and new exports.
* configure: Regenerate.
* include/bits/chrono_io.h (_ChronoSpec::_M_locale_specific):
Add new accessor functions to use a reserved bit in _Spec.
(__formatter_chrono::_M_parse): Use _M_locale_specific(true)
when chrono-specs contains locale-dependent conversion
specifiers.
(__formatter_chrono::_M_format): Open iconv descriptor if
conversion to UTF-8 will be needed.
(__formatter_chrono::_M_write): New function to write a
localized string with possible character conversion.
(__formatter_chrono::_M_a_A, __formatter_chrono::_M_b_B)
(__formatter_chrono::_M_p, __formatter_chrono::_M_r)
(__formatter_chrono::_M_x, __formatter_chrono::_M_X)
(__formatter_chrono::_M_locale_fmt): Use _M_write.
* include/bits/version.def (format): Update value.
* include/bits/version.h: Regenerate.
* include/std/format (_GLIBCXX_P2518R3): Check feature test
macro instead of __cplusplus.
(basic_format_context): Declare __formatter_chrono as friend.
* src/c++20/Makefile.am: Add new file.
* src/c++20/Makefile.in: Regenerate.
* src/c++20/format.cc: New file.
* testsuite/std/time/format_localized.cc: New test.
* testsuite/util/testsuite_abi.cc: Add new symbol version.
Like in r12-7519-g027e30414492d50feb2854aff38227b14300dc4b, I've done
git grep -v 'long long\|optab optab\|template template\|double double' | grep ' \([a-zA-Z]\+\) \1 '
This is just part of the changes, mostly for non-gcc directories.
I'll try to get to the rest soon. Obviously, the above command also
finds cases which are correct as is and shouldn't be changed, so one
needs to manually inspect everything.
I'd hope most of it is pretty obvious, but the config/ and libstdc++-v3/
hunks include a tweak in a license wording, though other copies of the
similar license have the wording right.
2024-04-02 Jakub Jelinek <jakub@redhat.com>
* Makefile.tpl: Fix duplicated words; returns returns ->
returns.
config/
* lcmessage.m4: Fix duplicated words; can can -> can,
package package -> package.
libdecnumber/
* decCommon.c (decFinalize): Fix duplicated words in
comment; the the -> the.
libgcc/
* unwind-dw2-fde.c (struct fde_accumulator): Fix duplicated
words in comment; is is -> is.
libgfortran/
* configure.host: Fix duplicated words; the the -> the.
libgm2/
* configure.host: Fix duplicated words; the the -> the.
libgomp/
* libgomp.texi (OpenMP 5.2): Fix duplicated words; with with ->
with.
(omp_target_associate_ptr): Fix duplicated words; either either ->
either.
(omp_init_allocator): Fix duplicated words; be be -> be.
(omp_realloc): Fix duplicated words; is is -> is.
(OMP_ALLOCATOR): Fix duplicated words; other other -> other.
* priority_queue.h (priority_queue_multi_p): Fix duplicated words;
to to -> to.
libiberty/
* regex.c (byte_re_match_2_internal): Fix duplicated words in comment;
next next -> next.
* dyn-string.c (dyn_string_init): Fix duplicated words in comment;
of of -> of.
libitm/
* beginend.cc (GTM::gtm_thread::begin_transaction): Fix duplicated
words in comment; not not -> not to.
libobjc/
* init.c (duplicate_classes): Fix duplicated words in comment; in in
-> in.
* sendmsg.c (__objc_prepare_dtable_for_class): Fix duplicated words
in comment; the the -> the.
* encoding.c (objc_layout_structure): Likewise.
libstdc++-v3/
* acinclude.m4: Fix duplicated words; file file -> file can.
* configure.host: Fix duplicated words; the the -> the.
libvtv/
* vtv_rts.cc (vtv_fail): Fix duplicated words; to to -> to.
* vtv_fail.cc (vtv_fail): Likewise.
The <xlocale.h> header is needed for newlocale and locale_t on these
targets.
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_CHECK_TEXT_ENCODING): Use <xlocale.h> if
needed for newlocale.
* configure: Regenerate.
* src/c++26/text_encoding.cc: Use <xlocale.h>.
Reviewed-by: Iain Sandoe <iain@sandoe.co.uk>
This is another C++26 change, approved in Varna 2023. We require a new
static array of data that is extracted from the IANA Character Sets
database. A new Python script to generate a header from the IANA CSV
file is added.
The text_encoding class is basically just a pointer to an {ID,name} pair
in the static array. The aliases view is also just the same pointer (or
empty), and the view's iterator moves forwards and backwards in the
array while the array elements have the same ID (or to one element
further, for a past-the-end iterator).
Because those iterators refer to a global array that never goes out of
scope, there's no reason they should every produce undefined behaviour
or indeterminate values. They should either have well-defined
behaviour, or abort. The overhead of ensuring those properties is pretty
low, so seems worth it.
This means that an aliases_view iterator should never be able to access
out-of-bounds. A non-value-initialized iterator always points to an
element of the static array even when not dereferenceable (the array has
unreachable entries at the start and end, which means that even a
past-the-end iterator for the last encoding in the array still points to
valid memory). Dereferencing an iterator can always return a valid
array element, or "" for a non-dereferenceable iterator (but doing so
will abort when assertions are enabled). In the language being proposed
for C++26, dereferencing an invalid iterator erroneously returns "".
Attempting to increment/decrement past the last/first element in the
view is erroneously a no-op, so aborts when assertions are enabled, and
doesn't change value otherwise.
Similarly, constructing a std::text_encoding with an invalid id (one
that doesn't have the value of an enumerator) erroneously behaves the
same as constructing with id::unknown, or aborts with assertions
enabled.
libstdc++-v3/ChangeLog:
PR libstdc++/113318
* acinclude.m4 (GLIBCXX_CONFIGURE): Add c++26 directory.
(GLIBCXX_CHECK_TEXT_ENCODING): Define.
* config.h.in: Regenerate.
* configure: Regenerate.
* configure.ac: Use GLIBCXX_CHECK_TEXT_ENCODING.
* include/Makefile.am: Add new headers.
* include/Makefile.in: Regenerate.
* include/bits/locale_classes.h (locale::encoding): Declare new
member function.
* include/bits/unicode.h (__charset_alias_match): New function.
* include/bits/text_encoding-data.h: New file.
* include/bits/version.def (text_encoding): Define.
* include/bits/version.h: Regenerate.
* include/std/text_encoding: New file.
* src/Makefile.am: Add new subdirectory.
* src/Makefile.in: Regenerate.
* src/c++26/Makefile.am: New file.
* src/c++26/Makefile.in: New file.
* src/c++26/text_encoding.cc: New file.
* src/experimental/Makefile.am: Include c++26 convenience
library.
* src/experimental/Makefile.in: Regenerate.
* python/libstdcxx/v6/printers.py (StdTextEncodingPrinter): New
printer.
* scripts/gen_text_encoding_data.py: New file.
* testsuite/22_locale/locale/encoding.cc: New test.
* testsuite/ext/unicode/charset_alias_match.cc: New test.
* testsuite/std/text_encoding/cons.cc: New test.
* testsuite/std/text_encoding/members.cc: New test.
* testsuite/std/text_encoding/requirements.cc: New test.
Reviewed-by: Ulrich Drepper <drepper.fsp@gmail.com>
Reviewed-by: Patrick Palka <ppalka@redhat.com>
PR libbacktrace/111315
PR libbacktrace/112263
* acinclude.m4: Set -D_GNU_SOURCE in BACKTRACE_CPPFLAGS and when
grepping link.h for dl_iterate_phdr.
* configure: Regenerate.
The checks for snprintf give a -Wformat warning due to a missing
argument.
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_ENABLE_C99): Fix snprintf checks.
* configure: Regenerate.
The new __basic_file::native_handle() function can be added for C++11
and above, because the names "native_handle" and "native_handle_type"
are already reserved since C++11. Exporting those symbols from the
shared library does no harm, even if the feature gets dropped before the
C++23 standard is final.
The new member functions of std::fstream etc. are only declared for
C++26 and so are not instantiated in src/c++11/fstream-inst.cc. Declare
them with the always_inline attribute so that no symbol definitions are
needed in the library (we can change this later when C++26 support is
less experimental).
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_CHECK_FILEBUF_NATIVE_HANDLES): New
macro.
* config.h.in: Regenerate.
* config/abi/pre/gnu.ver (GLIBCXX_3.4.32): Export new
basic_filebuf members.
* config/io/basic_file_stdio.cc (__basic_file::native_handle):
Define new function.
* config/io/basic_file_stdio.h (__basic_file::native_handle):
Declare new function.
* configure: Regenerate.
* configure.ac: Use GLIBCXX_CHECK_FILEBUF_NATIVE_HANDLES.
* include/bits/version.def (fstream_native_handles): New macro.
* include/bits/version.h: Regenerate.
* include/std/fstream (basic_filebuf::native_handle)
(basic_fstream::native_handle, basic_ifstream::native_handle)
(basic_ofstream::native_handle): New functions.
* src/c++11/Makefile.am: Move compilation of basic_file.cc,
locale_init.cc and localename.cc to here.
* src/c++11/Makefile.in: Regenerate.
* src/c++98/locale_init.cc: Moved to...
* src/c++11/locale_init.cc: ...here.
* src/c++98/localename.cc: Moved to...
* src/c++11/localename.cc: ...here.
* src/c++98/Makefile.am: Remove basic_file.cc, locale_init.cc
and localename.cc from here.
* src/c++98/Makefile.in: Regenerate.
* testsuite/27_io/basic_filebuf/native_handle/version.cc: New test.
* testsuite/27_io/basic_fstream/native_handle/char/1.cc: New test.
* testsuite/27_io/basic_fstream/native_handle/wchar_t/1.cc: New test.
* testsuite/27_io/basic_ifstream/native_handle/char/1.cc: New test.
* testsuite/27_io/basic_ifstream/native_handle/wchar_t/1.cc: New test.
* testsuite/27_io/basic_ofstream/native_handle/char/1.cc: New test.
* testsuite/27_io/basic_ofstream/native_handle/wchar_t/1.cc: New test.
This consolidates the three static archives for extensions into one, so
that -lstdc++exp can be used to provide the definitions of all unstable
library features.
The libstdc++_libbacktrace.a archive is now just a "noinst" convenience
library that is only used during the build, not installed. Its contents
are added to libstdc++exp.a, along with the new non-inline definitions
of std::stacktrace symbols.
The libstdc++fs.a archive is still installed, but its contents are
duplicated in libstdc++exp.a now. This means -lstdc++exp can be used
instead of -lstdc++fs. For targets using the GNU linker we should
consider replacing libstdc++fs.a with a linker script that does
INPUT(libstdc++exp.a).
The tests for <experimental/filesystem> could be changed to use
-lstdc++exp instead of -lstdc++fs, which would allow removing
src/filesystem/.libs from the LDFLAGS in scripts/testsuite_flags.in,
but that can be done at a later date.
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_CONFIGURE): Add c++23 directory.
* configure: Regenerate.
* doc/html/manual/*: Regenerate.
* doc/xml/manual/using.xml: Update documentation on linking.
* include/std/stacktrace: Remove declarations of libbacktrace
APIs.
(stacktrace_entry::_S_err_handler, stacktrace_entry::_S_init):
Remove.
(stacktrace_entry::_Info): New class.
(stacktrace_entry::_M_get_info): Use _Info.
(__stacktrace_impl): New class.
(basic_stacktrace): Derive from __stacktrace_impl.
(basic_stacktrace::current): Use __stacktrace_impl::_S_current.
* scripts/testsuite_flags.in: Adjust LDFLAGS to find
libstdc++exp instead of libstdc++_libbacktrace.
* src/Makefile.am (SUBDIRS): Add c++23 directory.
* src/Makefile.in: Regenerate.
* src/c++20/Makefile.am: Fix comment.
* src/c++20/Makefile.in: Regenerate.
* src/c++23/Makefile.am: New file.
* src/c++23/Makefile.in: New file.
* src/c++23/stacktrace.cc: New file with definitions of
stacktrace_entry::_Info and __stacktrace_impl members.
* src/experimental/Makefile.am: Use LIBADD to include other
libraries.
* src/experimental/Makefile.in: Regenerate.
* src/libbacktrace/Makefile.am: Use noinst_LTLIBRARIES.
* src/libbacktrace/Makefile.in: Regenerate.
* testsuite/19_diagnostics/stacktrace/current.cc: Adjust
dg-options to use -lstdc++exp.
* testsuite/19_diagnostics/stacktrace/entry.cc: Likewise.
* testsuite/19_diagnostics/stacktrace/stacktrace.cc: Likewise.
* testsuite/23_containers/vector/debug/assign4_backtrace_neg.cc:
Likewise.
The URI for namespaced docbook-xsl was updated to reflect the current
DocBook upstream at <https://cdn.docbook.org/>.
libstdc++-v3/Changelog:
* acinclude.m4: Update docbook xsl URI.
* configure: Regenerate.
The filesystem code was using these functions without checking for their
existence, assuming that any UNIX-like libc with <unistd.h> would always
provide them. That's not true for some newlib targets like arm-eabi.
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_CHECK_FILESYSTEM_DEPS): Check for mkdir,
chmod, chdir, and getcwd.
* config.h.in: Regenerate.
* configure: Regenerate.
* src/c++17/fs_ops.cc (create_dir): Use USE_MKDIR macro.
(fs::current_path): Use USE_GETCWD and USE_CHDIR macros.
(fs::permissions): Use USE_CHMOD macro.
* src/filesystem/ops-common.h [FILESYSTEM_IS_WINDOWS]
(chmod, mkdir, getcwd, chdir): Define new macros.
[FILESYSTEM_IS_WINDOWS] (chmod, mkdir, getcwd, chdir): Use
new macros.
* src/filesystem/ops.cc (create_dir): Use USE_MKDIR macro.
(fs::current_path): Use USE_GETCWD and USE_CHDIR macros.
(fs::permissions): Use USE_CHMOD macro.
This causes libstdc++_libbacktrace.a to be built by default. This might
fail on some targets, in which case we can make the 'auto' choice expand
to either 'yes' or 'no' depending on the target.
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_ENABLE_BACKTRACE): Default to yes.
* configure: Regenerate.
When configured with --enable-cstdio=stdio_pure we need to consistently
use fseek and not mix seeks on the file descriptor with reads and writes
on the FILE stream.
There are also a number of bugs related to error handling and return
values, because fread and fwrite return 0 on error, not -1, and fseek
returns 0 on success, not the file offset.
libstdc++-v3/ChangeLog:
PR libstdc++/110574
* acinclude.m4 (GLIBCXX_CHECK_LFS): Check for fseeko and ftello
and define _GLIBCXX_USE_FSEEKO_FTELLO.
* config.h.in: Regenerate.
* configure: Regenerate.
* config/io/basic_file_stdio.cc (xwrite) [_GLIBCXX_USE_STDIO_PURE]:
Check for fwrite error correctly.
(__basic_file<char>::xsgetn) [_GLIBCXX_USE_STDIO_PURE]: Check for
fread error correctly.
(get_file_offset): New function.
(__basic_file<char>::seekoff) [_GLIBCXX_USE_STDIO_PURE]: Use
fseeko if available. Use get_file_offset instead of return value
of fseek.
(__basic_file<char>::showmanyc): Use get_file_offset.
The __has_attribute(init_priority) check in <iostream> is true for Clang
on darwin, which means that user code including <iostream> thinks the
library will initialize the global streams. However, when libstdc++ is
built by GCC on darwin, the __has_attribute(init_priority) check is
false, which means that the library thinks that user code will do the
initialization when <iostream> is included. This means that the
initialization is never done.
Add an autoconf check so that the header and the library both make their
decision based on the static properties of GCC at build time, with a
consistent outcome.
As a belt and braces check, also do the initialization in <iostream> if
the compiler including that header doesn't support the attribute (even
if the library also containers the initialization). This might result in
redundant initialization done in <iostream>, but ensures the
initialization happens somewhere if there's any doubt about the
attribute working correctly due to missing linker support.
libstdc++-v3/ChangeLog:
PR libstdc++/110432
* acinclude.m4 (GLIBCXX_CHECK_INIT_PRIORITY): New.
* config.h.in: Regenerate.
* configure: Regenerate.
* configure.ac: Use GLIBCXX_CHECK_INIT_PRIORITY.
* include/std/iostream: Use new autoconf macro as well as
__has_attribute.
* src/c++98/ios_base_init.h: Use new autoconf macro instead of
__has_attribute.
Reviewed-by: Patrick Palka <ppalka@redhat.com>
Although the copy_file_range(2) man page shows the arguments as off64_t*
that is not portable. For musl there is no off64_t type, as off_t is
always 64-bit. Use the loff_t type which is always 64-bit even if off_t
isn't. We could just use off_t because the filesystem library is
compiled with _FILE_OFFSET_BITS=64, but loff_t is the more correct type
for this interface.
libstdc++-v3/ChangeLog:
PR libstdc++/110462
* acinclude.m4 (GLIBCXX_CHECK_FILESYSTEM_DEPS): Check that
copy_file_range can be called with loff_t* arguments.
* configure: Regenerate.
* src/filesystem/ops-common.h (copy_file_copy_file_range):
Use loff_t for offsets.
The addition of __cxa_call_terminate@@CXXABI_1.3.15 on trunk means we
need a new version.
libstdc++-v3/ChangeLog:
* acinclude.m4 (libtool_VERSION): Update to 6.0.33.
* configure: Regenerate.
* doc/xml/manual/abi.xml: Add libstdc++.so.6.0.33.
* doc/html/manual/abi.html: Regenerate.
copy_file_range is a recent-ish syscall for copying files. It is similar
to sendfile but allows filesystem-specific optimizations. Common are:
Reflinks: BTRFS, XFS, ZFS (does not implement the syscall yet)
Server-side copy: NFS, SMB, Ceph
If copy_file_range is not available for the given files, fall back to
sendfile / userspace copy.
libstdc++-v3/ChangeLog:
* acinclude.m4 (_GLIBCXX_USE_COPY_FILE_RANGE): Define.
* config.h.in: Regenerate.
* configure: Regenerate.
* src/filesystem/ops-common.h (copy_file_copy_file_range):
Define new function.
(do_copy_file): Use it.
Signed-off-by: Jannik Glückert <jannik.glueckert@gmail.com>
We were previously only using sendfile for files smaller than 2GB, as
sendfile needs to be called repeatedly for files bigger than that.
Some quick numbers, copying a 16GB file, average of 10 repetitions:
old:
real: 13.4s
user: 0.14s
sys : 7.43s
new:
real: 8.90s
user: 0.00s
sys : 3.68s
libstdc++-v3/ChangeLog:
* acinclude.m4 (_GLIBCXX_HAVE_LSEEK): Define.
* config.h.in: Regenerate.
* configure: Regenerate.
* src/filesystem/ops-common.h (copy_file_sendfile): Define new
function for sendfile logic. Loop to support large files. Skip
zero-length files.
(do_copy_file): Use it.
Signed-off-by: Jannik Glückert <jannik.glueckert@gmail.com>
This should make it possible to use openlibm with djgpp (and other
targets with missing C99 <math.h> functions). The <math.h> from openlibm
provides all the functions, but not the float_t and double_t typedefs.
By separating the autoconf checks for the functionsand the typedefs, we
don't disable support for all the functions just because those typedefs
are not present.
libstdc++-v3/ChangeLog:
PR libstdc++/109818
* acinclude.m4 (GLIBCXX_ENABLE_C99): Add separate check for
float_t and double_t and define HAVE_C99_FLT_EVAL_TYPES.
* config.h.in: Regenerate.
* configure: Regenerate.
* include/c_global/cmath (float_t, double_t): Guard using new
_GLIBCXX_HAVE_C99_FLT_EVAL_TYPES macro.
Similar to the three commits r14-908, r14-909 and r14-910, the
_GLIBCXX_USE_C99_MATH_TR1 macro is misleading when it is also used for
<cmath>, not only for <tr1/cmath> headers. It is also wrong, because the
configure checks for TR1 use -std=c++98 and a target might define the
C99 features for C++11 but not for C++98.
Add separate configure checks for the <math.h> functions using
-std=c++11 for the checks. Use the new macro defined by those checks in
the C++11-specific parts of <cmath>, and in <complex>, <random> etc.
The check that defines _GLIBCXX_NO_C99_ROUNDING_FUNCS is only needed for
the C++11 <cmath> checks, so remove that from GLIBCXX_CHECK_C99_TR1 and
only do it for GLIBCXX_ENABLE_C99.
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_ENABLE_C99): Add checks for C99 math
functions and define _GLIBCXX_USE_C99_MATH_FUNCS. Move checks
for C99 rounding functions to here.
(GLIBCXX_CHECK_C99_TR1): Remove checks for C99 rounding
functions from here.
* config.h.in: Regenerate.
* configure: Regenerate.
* include/bits/random.h: Use _GLIBCXX_USE_C99_MATH_FUNCS instead
of _GLIBCXX_USE_C99_MATH_TR1.
* include/bits/random.tcc: Likewise.
* include/c_compatibility/math.h: Likewise.
* include/c_global/cmath: Likewise.
* include/ext/random: Likewise.
* include/ext/random.tcc: Likewise.
* include/std/complex: Likewise.
* testsuite/20_util/from_chars/4.cc: Likewise.
* testsuite/20_util/from_chars/8.cc: Likewise.
* testsuite/26_numerics/complex/proj.cc: Likewise.
* testsuite/26_numerics/headers/cmath/60401.cc: Likewise.
* testsuite/26_numerics/headers/cmath/types_std_c++0x.cc:
Likewise.
* testsuite/lib/libstdc++.exp (check_v3_target_cstdint):
Likewise.
* testsuite/util/testsuite_random.h: Likewise.
The -mlarge model for msp430-elf uses 20-bit pointers, which means that
sizeof(void*) == 4 and so the r14-1432-g51cf0b3949b88b change gives the
wrong answer. Check __INTPTR_WIDTH__ >= 32 instead.
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_ZONEINFO_DIR): Fix for 32-bit pointers
to check __INT_PTR_WIDTH__ instead of sizeof(void*).
* configure: Regenerate.
DJGPP (and maybe other targets) uses MAX_OFILE_ALIGNMENT=16 which means
that globals (and static objects) can't have alignment greater than 16.
This causes an error for the locks defined in src/c++11/shared_ptr.cc
because we try to align them to the cacheline size, to avoid false
sharing.
Add a configure check for the increased alignment, and live with false
sharing where we can't increase the alignment.
libstdc++-v3/ChangeLog:
PR libstdc++/109741
* acinclude.m4 (GLIBCXX_CHECK_ALIGNAS_CACHELINE): Define.
* config.h.in: Regenerate.
* configure: Regenerate.
* configure.ac: Use GLIBCXX_CHECK_ALIGNAS_CACHELINE.
* src/c++11/shared_ptr.cc (__gnu_internal::get_mutex): Do not
align lock table if not supported. use __GCC_DESTRUCTIVE_SIZE
instead of hardcoded 64.
As with the two commits before this, the _GLIBCXX_USE_C99_CTYPE_TR1 and
_GLIBCXX_USE_C99_FENV_TR1 macros are misleading when they are also used
for <cctype> and <cfenv>, not only for TR1 headers. It is also wrong,
because the configure checks for TR1 use -std=c++98 and a target might
define the C99 features for C++11 but not for C++98.
Add separate configure checks for the <ctype.h> and <fenv.h> features using -std=c++11
for the checks. Use the new macros defined by those checks in the
C++11-specific parts of <cctype>, <cfenv>, and <fenv.h>.
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_USE_C99): Check for isblank in C++11
mode and define _GLIBCXX_USE_C99_CTYPE. Check for <fenv.h>
functions in C++11 mode and define _GLIBCXX_USE_C99_FENV.
* config.h.in: Regenerate.
* configure: Regenerate.
* include/c_compatibility/fenv.h: Check _GLIBCXX_USE_C99_FENV
instead of _GLIBCXX_USE_C99_FENV_TR1.
* include/c_global/cfenv: Likewise.
* include/c_global/cctype: Check _GLIBCXX_USE_C99_CTYPE instead
of _GLIBCXX_USE_C99_CTYPE_TR1.
The _GLIBCXX_USE_C99_STDINT_TR1 macro (and the comments about it in
acinclude.m4 and config.h) are misleading when it is also used for
<stdint>, not only <tr1/stdint>. It is also wrong, because the
configure checks for TR1 use -std=c++98 and a target might define
uint32_t etc. for C++11 but not for C++98.
Add a separate configure check for the <stdint.h> types using -std=c++11
for the checks. Use the result of that separate check in <cstdint> and
most other places that still depend on the macro (many uses of that
macro have been removed already). The remaining uses of the STDINT_TR1
macro are really for TR1, or are in the src/c++11/compatibility-*.cc
files, where we don't want/need to change the condition they depend on
(if those symbols were only exported when <stdint.h> types were
available for -std=c++98, then that's the condition we should continue
to use for whether to export the compat symbols now).
Make similar changes for the related _GLIBCXX_USE_C99_INTTYPES_TR1 and
_GLIBCXX_USE_C99_INTTYPES_WCHAR_T_TR1 macros, adding new macros for
non-TR1 uses.
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_USE_C99): Check for <stdint.h> types in
C++11 mode and define _GLIBCXX_USE_C99_STDINT. Check for
<inttypes.h> features in C++11 mode and define
_GLIBCXX_USE_C99_INTTYPES and _GLIBCXX_USE_C99_INTTYPES_WCHAR_T.
* config.h.in: Regenerate.
* configure: Regenerate.
* doc/doxygen/user.cfg.in (PREDEFINED): Add new macros.
* include/bits/chrono.h: Check _GLIBCXX_USE_C99_STDINT instead
of _GLIBCXX_USE_C99_STDINT_TR1.
* include/c_compatibility/inttypes.h: Check
_GLIBCXX_USE_C99_INTTYPES and _GLIBCXX_USE_C99_INTTYPES_WCHAR_T
instead of _GLIBCXX_USE_C99_INTTYPES_TR1 and
_GLIBCXX_USE_C99_INTTYPES_WCHAR_T_TR1.
* include/c_compatibility/stdatomic.h: Check
_GLIBCXX_USE_C99_STDINT instead of _GLIBCXX_USE_C99_STDINT_TR1.
* include/c_compatibility/stdint.h: Likewise.
* include/c_global/cinttypes: Check _GLIBCXX_USE_C99_INTTYPES
and _GLIBCXX_USE_C99_INTTYPES_WCHAR_T instead of
_GLIBCXX_USE_C99_INTTYPES_TR1 and
_GLIBCXX_USE_C99_INTTYPES_WCHAR_T_TR1.
* include/c_global/cstdint: Check _GLIBCXX_USE_C99_STDINT
instead of _GLIBCXX_USE_C99_STDINT_TR1.
* include/std/atomic: Likewise.
* src/c++11/cow-stdexcept.cc: Likewise.
* testsuite/29_atomics/headers/stdatomic.h/c_compat.cc:
Likewise.
* testsuite/lib/libstdc++.exp (check_v3_target_cstdint):
Likewise.
The _GLIBCXX_USE_C99_COMPLEX_TR1 macro (and the comments about it in
acinclude.m4 and config.h) are misleading when it is also used for
<complex>, not only <tr1/complex>. It is also wrong, because the
configure checks for TR1 use -std=c++98 and a target might define cacos
etc. for C++11 but not for C++98.
Add a separate configure check for the inverse trigonometric functions
that are covered by _GLIBCXX_USE_C99_COMPLEX_TR1, but using -std=c++11
for the checks. Use the result of that separate check in <complex>.
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_USE_C99): Check for complex inverse trig
functions in C++11 mode and define _GLIBCXX_USE_C99_COMPLEX_ARC.
* config.h.in: Regenerate.
* configure: Regenerate.
* doc/doxygen/user.cfg.in (PREDEFINED): Add new macro.
* include/std/complex: Check _GLIBCXX_USE_C99_COMPLEX_ARC
instead of _GLIBCXX_USE_C99_COMPLEX_TR1.
As noted in https://github.com/llvm/llvm-project/issues/62623 there are
no tsan interceptors for some of the new POSIX-1:202x APIs added by
https://austingroupbugs.net/view.php?id=1216 so tsan gives false
positive warnings for try_lock_for on timed mutexes.
Disable the uses of the new pthread_mutex_clocklock API when tsan is
active. This changes the semantics of the try_lock_for functions,
because it can change which clock is used for the wait. This means those
functions might be affected by system clock adjustments when tsan is
used, when they would not be affected otherwise.
Reviewed-by: Thomas Rodgers <trodgers@redhat.com>
Reviewed-by: Mike Crowe <mac@mcrowe.com>
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_CHECK_PTHREAD_MUTEX_CLOCKLOCK): Define
_GLIBCXX_USE_PTHREAD_MUTEX_CLOCKLOCK in terms of _GLIBCXX_TSAN.
* configure: Regenerate.
We should not test for nan by passing it a null pointer, as this can
trigger -Wnonnull warnings.
Also fix an outdated comment about the default -std mode.
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_CHECK_C99_TR1): Use a non-null pointer
to check for nan, nanf, and nanl.
* configure: Regenerate.
GCC used to emit an instance of an empty ios_base::Init class in
every TU which included <iostream> to ensure it is std::cout etc.
is initialized, but thanks to Patrick work on some targets (which have
init_priority attribute support) it is now initialized only inside of
libstdc++.so.6/libstdc++.a.
This causes a problem if people do something that has never been supported,
try to run GCC 13 compiled C++ code against GCC 12 or earlier
libstdc++.so.6 - std::cout etc. are then never initialized because code
including <iostream> expects the library to initialize it and the library
expects code including <iostream> to do that.
The following patch is second attempt to make this work cheaply as the
earlier attempt of aliasing the std::cout etc. symbols with another symbol
version didn't work out due to copy relocation breaking the aliases appart.
The patch forces just a _ZSt21ios_base_library_initv undefined symbol
into all *.o files which include <iostream> and while there is no runtime
relocation against that, it seems to enforce the right version of
libstdc++.so.6. /home/jakub/src/gcc/obj08i/usr/local/ is the install
directory of trunk patched with this patch, /home/jakub/src/gcc/obj06/
is builddir of trunk without this patch, system g++ is GCC 12.1.1.
$ cat /tmp/hw.C
#include <iostream>
int
main ()
{
std::cout << "Hello, world!" << std::endl;
}
$ cd /home/jakub/src/gcc/obj08i/usr/local/bin
$ ./g++ -o /tmp/hw /tmp/hw.C
$ readelf -Wa /tmp/hw 2>/dev/null | grep initv
4: 0000000000000000 0 FUNC GLOBAL DEFAULT UND _ZSt21ios_base_library_initv@GLIBCXX_3.4.32 (4)
71: 0000000000000000 0 FUNC GLOBAL DEFAULT UND _ZSt21ios_base_library_initv@GLIBCXX_3.4.32
$ /tmp/hw
/tmp/hw: /lib64/libstdc++.so.6: version `GLIBCXX_3.4.32' not found (required by /tmp/hw)
$ LD_LIBRARY_PATH=/home/jakub/src/gcc/obj08i/usr/local/lib64/ /tmp/hw
Hello, world!
$ LD_LIBRARY_PATH=/home/jakub/src/gcc/obj06/x86_64-pc-linux-gnu/libstdc++-v3/src/.libs/ /tmp/hw
/tmp/hw: /home/jakub/src/gcc/obj06/x86_64-pc-linux-gnu/libstdc++-v3/src/.libs/libstdc++.so.6: version `GLIBCXX_3.4.32' not found (required by /tmp/hw)
$ g++ -o /tmp/hw /tmp/hw.C
$ /tmp/hw
Hello, world!
$ LD_LIBRARY_PATH=/home/jakub/src/gcc/obj06/x86_64-pc-linux-gnu/libstdc++-v3/src/.libs/ /tmp/hw
Hello, world!
$ LD_LIBRARY_PATH=/home/jakub/src/gcc/obj08i/usr/local/lib64/ /tmp/hw
Hello, world!
On sparc-sun-solaris2.11 one I've actually checked a version which had
defined(_GLIBCXX_SYMVER_SUN) next to defined(_GLIBCXX_SYMVER_GNU), but
init_priority attribute doesn't seem to be supported there and so I couldn't
actually test how this works there. Using gas and Sun ld, Rainer, does one
need to use gas + gld for init_priority or something else?
2023-04-28 Jakub Jelinek <jakub@redhat.com>
PR libstdc++/108969
* config/abi/pre/gnu.ver (GLIBCXX_3.4.32): Export
_ZSt21ios_base_library_initv.
* testsuite/util/testsuite_abi.cc (check_version): Add GLIBCXX_3.4.32
symver and make it the latestp.
* src/c++98/ios_init.cc (ios_base_library_init): New alias.
* acinclude.m4 (libtool_VERSION): Change to 6:32:0.
* include/std/iostream: If init_priority attribute is supported
and _GLIBCXX_SYMVER_GNU, force undefined _ZSt21ios_base_library_initv
symbol into the object.
* configure: Regenerated.
The string literal containing the static tzdata.zi information is too
large for some targets, so do not enable it by default for avr-*-* and
msp430-*-*.
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_ZONEINFO_DIR) [avr-*-*, msp430-*-*]: Set
embed_zoneinfo=no
* configure: Regenerate.
The config for --with-libstdcxx-zoneinfo=yes was comparing the target
triplet to "gnu* | linux* | kfreebsd*-gnu | knetbsd*-gnu" which is only
the last component of the triplet, so failed to match and always used
the zoneinfo_dir=none default. Check $target_os instead.
There was also an error in the check for native builds that tzdata.zi is
actually present in the configured directory. That meant a warning was
printed even when the file was present:
configure: zoneinfo data directory: /usr/share/zoneinfo
configure: WARNING: "/usr/share/zoneinfo does not contain tzdata.zi file"
configure: static tzdata.zi file will be compiled into the library
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_ZONEINFO_DIR): Check $target_os instead
of $host. Fix check for file being present during native build.
* configure: Regenerate.
This adds a copy of the tzdata.zi file to the library, and allows
configuring to use it instead of a copy read from disk at runtime.
The content of the file is in the public domain, but will need to be
updated to the latest upstream file before making GCC releases.
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_ZONEINFO_DIR): Replace the
--with-libstdcxx-zoneinfo-dir configure option with
--with-libstdcxx-zoneinfo with yes/no/static choices as well as
a directory.
* config.h.in: Regenerate.
* configure: Regenerate.
* doc/xml/manual/configure.xml: Document configure option.
* doc/html/manual/configure.html: Regenerate.
* src/c++20/Makefile.am: Generate tzdata.zi.h header.
* src/c++20/Makefile.in: Regenerate.
* src/c++20/tzdb.cc (__gnu_cxx::zoneinfo_dir_override): Return a
null pointer if no directory is configured.
(zoneinfo_dir): Replace with ...
(zoneinfo_file): New function.
(tzdata_stream): New istream class.
(remote_version, reload_tzdb): Use tzdata_stream.
* testsuite/lib/libstdc++.exp (check_effective_target_tzdb):
Check new _GLIBCXX_STATIC_TZDATA macro and ignore presence of
tzdata.zi file in default location.
* src/c++20/tzdata.zi: New file.
This reimplements the GNU threads library on native Windows (except for the
Objective-C specific subset) using direct Win32 API calls, in lieu of the
implementation based on semaphores. This base implementations requires
Windows XP/Server 2003, which was the default minimal setting of MinGW-W64
until end of 2020. This also adds the support required for the C++11 threads,
using again direct Win32 API calls; this additional layer requires Windows
Vista/Server 2008 and is enabled only if _WIN32_WINNT >= 0x0600.
This also changes libstdc++ to pass -D_WIN32_WINNT=0x0600 but only when the
switch --enable-libstdcxx-threads is passed, which means that C++11 threads
are still disabled by default *unless* MinGW-W64 itself is configured for
Windows Vista/Server 2008 or later by default (this has been the case in
the development version since end of 2020, for earlier versions you can
configure it --with-default-win32-winnt=0x0600 to get the same effect).
I only manually tested it on i686-w64-mingw32 and x86_64-w64-mingw32 but
AdaCore has used it in their C/C++/Ada compilers for 3 years now and the
30_threads chapter of the libstdc++ testsuite was clean at the time.
2022-10-31 Eric Botcazou <ebotcazou@adacore.com>
libgcc/
* config.host (i[34567]86-*-mingw*): Add thread fragment after EH one
as well as new i386/t-slibgcc-mingw fragment.
(x86_64-*-mingw*): Likewise.
* config/i386/gthr-win32.h: If _WIN32_WINNT is at least 0x0600, define
both __GTHREAD_HAS_COND and __GTHREADS_CXX0X to 1.
Error out if _GTHREAD_USE_MUTEX_TIMEDLOCK is 1.
Include stdlib.h instead of errno.h and do not include _mingw.h.
(CONST_CAST2): Add specific definition for C++.
(ATTRIBUTE_UNUSED): New macro.
(__UNUSED_PARAM): Delete.
Define WIN32_LEAN_AND_MEAN before including windows.h.
(__gthread_objc_data_tls): Use TLS_OUT_OF_INDEXES instead of (DWORD)-1.
(__gthread_objc_init_thread_system): Likewise.
(__gthread_objc_thread_get_data): Minor tweak.
(__gthread_objc_condition_allocate): Use ATTRIBUTE_UNUSED.
(__gthread_objc_condition_deallocate): Likewise.
(__gthread_objc_condition_wait): Likewise.
(__gthread_objc_condition_broadcast): Likewise.
(__gthread_objc_condition_signal): Likewise.
Include sys/time.h.
(__gthr_win32_DWORD): New typedef.
(__gthr_win32_HANDLE): Likewise.
(__gthr_win32_CRITICAL_SECTION): Likewise.
(__gthr_win32_CONDITION_VARIABLE): Likewise.
(__gthread_t): Adjust.
(__gthread_key_t): Likewise.
(__gthread_mutex_t): Likewise.
(__gthread_recursive_mutex_t): Likewise.
(__gthread_cond_t): New typedef.
(__gthread_time_t): Likewise.
(__GTHREAD_MUTEX_INIT_DEFAULT): Delete.
(__GTHREAD_RECURSIVE_MUTEX_INIT_DEFAULT): Likewise.
(__GTHREAD_COND_INIT_FUNCTION): Define.
(__GTHREAD_TIME_INIT): Likewise.
(__gthr_i486_lock_cmp_xchg): Delete.
(__gthr_win32_create): Declare.
(__gthr_win32_join): Likewise.
(__gthr_win32_self): Likewise.
(__gthr_win32_detach): Likewise.
(__gthr_win32_equal): Likewise.
(__gthr_win32_yield): Likewise.
(__gthr_win32_mutex_destroy): Likewise.
(__gthr_win32_cond_init_function): Likewise if __GTHREADS_HAS_COND is 1.
(__gthr_win32_cond_broadcast): Likewise.
(__gthr_win32_cond_signal): Likewise.
(__gthr_win32_cond_wait): Likewise.
(__gthr_win32_cond_timedwait): Likewise.
(__gthr_win32_recursive_mutex_init_function): Delete.
(__gthr_win32_recursive_mutex_lock): Likewise.
(__gthr_win32_recursive_mutex_unlock): Likewise.
(__gthr_win32_recursive_mutex_destroy): Likewise.
(__gthread_create): New inline function.
(__gthread_join): Likewise.
(__gthread_self): Likewise.
(__gthread_detach): Likewise.
(__gthread_equal): Likewise.
(__gthread_yield): Likewise.
(__gthread_cond_init_function): Likewise if __GTHREADS_HAS_COND is 1.
(__gthread_cond_broadcast): Likewise.
(__gthread_cond_signal): Likewise.
(__gthread_cond_wait): Likewise.
(__gthread_cond_timedwait): Likewise.
(__GTHREAD_WIN32_INLINE): New macro.
(__GTHREAD_WIN32_COND_INLINE): Likewise.
(__GTHREAD_WIN32_ACTIVE_P): Likewise.
Define WIN32_LEAN_AND_MEAN before including windows.h.
(__gthread_once): Minor tweaks.
(__gthread_key_create): Use ATTRIBUTE_UNUSED and TLS_OUT_OF_INDEXES.
(__gthread_key_delete): Minor tweak.
(__gthread_getspecific): Likewise.
(__gthread_setspecific): Likewise.
(__gthread_mutex_init_function): Reimplement.
(__gthread_mutex_destroy): Likewise.
(__gthread_mutex_lock): Likewise.
(__gthread_mutex_trylock): Likewise.
(__gthread_mutex_unlock): Likewise.
(__gthr_win32_abs_to_rel_time): Declare.
(__gthread_recursive_mutex_init_function): Reimplement.
(__gthread_recursive_mutex_destroy): Likewise.
(__gthread_recursive_mutex_lock): Likewise.
(__gthread_recursive_mutex_trylock): Likewise.
(__gthread_recursive_mutex_unlock): Likewise.
(__gthread_cond_destroy): New inline function.
(__gthread_cond_wait_recursive): Likewise.
* config/i386/gthr-win32.c: Delete everything.
Include gthr-win32.h to get the out-of-line version of inline routines.
Add compile-time checks for the local version of the Win32 types.
* config/i386/gthr-win32-cond.c: New file.
* config/i386/gthr-win32-thread.c: Likewise.
* config/i386/t-gthr-win32: Add config/i386/gthr-win32-thread.c to the
EH part, config/i386/gthr-win32-cond.c and config/i386/gthr-win32.c to
the static version of libgcc.
* config/i386/t-slibgcc-mingw: New file.
* config/i386/libgcc-mingw.ver: Likewise.
libstdc++-v3/
* acinclude.m4 (GLIBCXX_EXPORT_FLAGS): Substitute CPPFLAGS.
(GLIBCXX_ENABLE_LIBSTDCXX_TIME): Set ac_has_sched_yield and
ac_has_win32_sleep to yes for MinGW. Change HAVE_WIN32_SLEEP
into _GLIBCXX_USE_WIN32_SLEEP.
(GLIBCXX_CHECK_GTHREADS): Add _WIN32_THREADS to compilation flags for
Win32 threads and force _GTHREAD_USE_MUTEX_TIMEDLOCK to 0 for them.
Add -D_WIN32_WINNT=0x0600 to compilation flags if yes was configured
and add it to CPPFLAGS on success.
* config.h.in: Regenerate.
* configure: Likewise.
* config/os/mingw32-w64/os_defines.h (_GLIBCXX_USE_GET_NPROCS_WIN32):
Define to 1.
* config/os/mingw32/os_defines.h (_GLIBCXX_USE_GET_NPROCS_WIN32): Ditto
* src/c++11/thread.cc (get_nprocs): Provide Win32 implementation if
_GLIBCXX_USE_GET_NPROCS_WIN32 is defined. Replace HAVE_WIN32_SLEEP
with USE_WIN32_SLEEP.
* testsuite/19_diagnostics/headers/system_error/errc_std_c++0x.cc: Add
missing conditional compilation.
* testsuite/lib/libstdc++.exp (check_v3_target_sleep): Add support for
_GLIBCXX_USE_WIN32_SLEEP.
(check_v3_target_nprocs): Likewise for _GLIBCXX_USE_GET_NPROCS_WIN32.
Signed-off-by: Eric Botcazou <ebotcazou@adacore.com>
Signed-off-by: Jonathan Yong <10walls@gmail.com>
This is the largest missing piece of C++20 support. Only the cxx11 ABI
is supported, due to the use of std::string in the API for time zones.
For the old gcc4 ABI, utc_clock and leap seconds are supported, but only
using a hardcoded list of leap seconds, no up-to-date tzdb::leap_seconds
information is available, and no time zones or zoned_time conversions.
The implementation currently depends on a tzdata.zi file being provided
by the OS or the user. The expected location is /usr/share/zoneinfo but
that can be changed using --with-libstdcxx-zoneinfo-dir=PATH. On targets
that support it there is also a weak symbol that users can override in
their own program (which also helps with testing):
extern "C++" const char* __gnu_cxx::zoneinfo_dir_override();
If no file is found, a fallback tzdb object will be created which only
contains the "Etc/UTC" and "Etc/GMT" time zones.
A leapseconds file is also expected in the same directory, but if that
isn't present then a hardcoded list of leapseconds is used, which is
correct at least as far as 2023-06-28 (and it currently looks like no
leap second will be inserted for a few years).
The tzdata.zi and leapseconds files from https://www.iana.org/time-zones
are in the public domain, so shipping copies of them with GCC would be
an option. However, the tzdata.zi file will rapidly become outdated, so
users should really provide it themselves (or convince their OS vendor
to do so). It would also be possible to implement an alternative parser
for the compiled tzdata files (one per time zone) under
/usr/share/zoneinfo. Those files are present on more operating systems,
but do not contain all the information present in tzdata.zi.
Specifically, the "links" are not present, so that e.g. "UTC" and
"Universal" are distinct time zones, rather than both being links to the
canonical "Etc/UTC" zone. For some platforms those files are hard links
to the same file, but there's no indication which zone is the canonical
name and which is a link. Other platforms just store them in different
inodes anyway. I do not plan to add such an alternative parser for the
compiled files. That would need to be contributed by maintainers or
users of targets that require it, if making tzdata.zi available is not
an option. The library ABI would not need to change for a new tzdb
implementation, because everything in tzdb_list, tzdb and time_zone is
implemented as a pimpl (except for the shared_ptr links between nodes,
described below). That means the new exported symbols added by this
commit should be stable even if the implementation is completely
rewritten.
The information from tzdata.zi is parsed and stored in data structures
that closely model the info in the file. This is a space-efficient
representation that uses less memory that storing every transition for
every time zone. It also avoids spending time expanding that
information into time zone transitions that might never be needed by the
program. When a conversion to/from a local time to UTC is requested the
information will be processed to determine the time zone transitions
close to the time being converted.
There is a bug in some time zone transitions. When generating a sys_info
object immediately after one that was previously generated, we need to
find the previous rule that was in effect and note its offset and
letters. This is so that the start time and abbreviation of the new
sys_info will be correct. This only affects time zones that use a format
like "C%sT" where the LETTERS replacing %s are non-empty for standard
time, e.g. "Asia/Shanghai" which uses "CST" for standard time and "CDT"
for daylight time.
The tzdb_list structure maintains a linked list of tzdb nodes using
shared_ptr links. This allows the iterators into the list to share
ownership with the list itself. This offers a non-portable solution to a
lifetime issue in the API. Because tzdb objects can be erased from the
list using tzdb_list::erase_after, separate modules/libraries in a large
program cannot guarantee that any const tzdb& or const time_zone*
remains valid indefinitely. Holding onto a tzdb_list::const_iterator
will extend the tzdb object's lifetime, even if it's erased from the
list. An alternative design would be for the list iterator to hold a
weak_ptr. This would allow users to test whether the tzdb still exists
when the iterator is dereferenced, which is better than just having a
dangling raw pointer. That doesn't actually extend the tzdb's lifetime
though, and every use of it would need to be preceded by checking the
weak_ptr. Using shared_ptr adds a little bit of overhead but allows
users to solve the lifetime issue if they rely on the libstdc++-specific
iterator property.
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_ZONEINFO_DIR): New macro.
* config.h.in: Regenerate.
* config/abi/pre/gnu.ver: Export new symbols.
* configure: Regenerate.
* configure.ac (GLIBCXX_ZONEINFO_DIR): Use new macro.
* include/std/chrono (utc_clock::from_sys): Correct handling
of leap seconds.
(nonexistent_local_time::_M_make_what_str): Define.
(ambiguous_local_time::_M_make_what_str): Define.
(__throw_bad_local_time): Define new function.
(time_zone, tzdb_list, tzdb): Implement all members.
(remote_version, zoned_time, get_leap_second_info): Define.
* include/std/version: Add comment for __cpp_lib_chrono.
* src/c++20/Makefile.am: Add new file.
* src/c++20/Makefile.in: Regenerate.
* src/c++20/tzdb.cc: New file.
* testsuite/lib/libstdc++.exp: Define effective target tzdb.
* testsuite/std/time/clock/file/members.cc: Check file_time
alias and file_clock::now() member.
* testsuite/std/time/clock/gps/1.cc: Likewise for gps_clock.
* testsuite/std/time/clock/tai/1.cc: Likewise for tai_clock.
* testsuite/std/time/syn_c++20.cc: Uncomment everything except
parse.
* testsuite/std/time/clock/utc/leap_second_info.cc: New test.
* testsuite/std/time/exceptions.cc: New test.
* testsuite/std/time/time_zone/get_info_local.cc: New test.
* testsuite/std/time/time_zone/get_info_sys.cc: New test.
* testsuite/std/time/time_zone/requirements.cc: New test.
* testsuite/std/time/tzdb/1.cc: New test.
* testsuite/std/time/tzdb/leap_seconds.cc: New test.
* testsuite/std/time/tzdb_list/1.cc: New test.
* testsuite/std/time/tzdb_list/requirements.cc: New test.
* testsuite/std/time/zoned_time/1.cc: New test.
* testsuite/std/time/zoned_time/custom.cc: New test.
* testsuite/std/time/zoned_time/deduction.cc: New test.
* testsuite/std/time/zoned_time/req_neg.cc: New test.
* testsuite/std/time/zoned_time/requirements.cc: New test.
* testsuite/std/time/zoned_traits.cc: New test.
This moves two AC_MSG_RESULT lines for <uchar.h> features so that they
are only printed when the corresponding AC_MSG_CHECKING actually
happened. This fixes configure output like:
checking for uchar.h... no
no
checking for int64_t... yes
Also move the AC_MSG_CHECKING for libbacktrace support so it doesn't
come after AC_CHECK_HEADERS output. This fixes:
checking whether to build libbacktrace support... checking for sys/mman.h... (cached) yes
yes
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_CHECK_UCHAR_H): Don't use AC_MSG_RESULT
unless the AC_MSG_CHECKING happened.
* configure: Regenerate.
This patch adds the library support for the experimental C++ Contracts
implementation. This now consists only of a default definition of the
violation handler, which users can override through defining their own
version. To avoid ABI stability problems with libstdc++.so this is added to
a separate -lstdc++exp static library, which the driver knows to add when it
sees -fcontracts.
Co-authored-by: Andrew Marmaduke <amarmaduke@lock3software.com>
Co-authored-by: Jason Merrill <jason@redhat.com>
libstdc++-v3/ChangeLog:
* acinclude.m4 (glibcxx_SUBDIRS): Add src/experimental.
* include/Makefile.am (experimental_headers): Add contract.
* include/Makefile.in: Regenerate.
* src/Makefile.am (SUBDIRS): Add experimental.
* src/Makefile.in: Regenerate.
* configure: Regenerate.
* src/experimental/contract.cc: New file.
* src/experimental/Makefile.am: New file.
* src/experimental/Makefile.in: New file.
* include/experimental/contract: New file.
This saves us a build flag when building for freestanding targets.
libstdc++-v3/ChangeLog:
* acinclude.m4: Default hosted to off if building without
headers and without newlib.
* configure: Regenerate.
Implement a long-standing request to support tuning the size of the
emergency buffer for allocating exceptions after malloc fails, or to
disable that buffer entirely.
It's now possible to disable the dynamic allocation of the buffer and
use a fixed-size static buffer, via --enable-libstdcxx-static-eh-pool.
This is a built-time choice that is baked into libstdc++ and so affects
all code linked against that build of libstdc++.
The size of the pool can be set by --with-libstdcxx-eh-pool-obj-count=N
which is measured in units of sizeof(void*) not bytes. A given exception
type such as std::system_error depends on the target, so giving a size
in bytes wouldn't be portable across 16/32/64-bit targets.
When libstdc++ is configured to use a dynamic buffer, the size of that
buffer can now be tuned at runtime by setting the GLIBCXX_TUNABLES
environment variable (c.f. PR libstdc++/88264). The number of exceptions
to reserve space for is controlled by the "glibcxx.eh_pool.obj_count"
and "glibcxx.eh_pool.obj_size" tunables. The pool will be sized to be
able to allocate obj_count exceptions of size obj_size*sizeof(void*) and
obj_count "dependent" exceptions rethrown by std::rethrow_exception.
With the ability to tune the buffer size, we can reduce the default pool
size on 32-bit and 16-bit targets. Most users never need to throw 1kB
exceptions in parallel from hundreds of threads after malloc is OOM. The
users who do need that can use the tunables to select larger sizes.
The old defaults can be chosen at runtime by setting GLIBCXX_TUNABLES
to:
64-bit: glibcxx.eh_pool.obj_count=64:glibcxx.eh_pool.obj_size=112
32-bit: glibcxx.eh_pool.obj_count=32:glibcxx.eh_pool.obj_size=104
Or approximated by configuring with:
64-bit: --with-libstdcxx-eh-pool-obj-count=252
32-bit: --with-libstdcxx-eh-pool-obj-count=94
libstdc++-v3/ChangeLog:
PR libstdc++/68606
* Makefile.in: Regenerate.
* acinclude.m4 (GLIBCXX_EMERGENCY_EH_ALLOC): New macro.
* configure: Regenerate.
* configure.ac: Use GLIBCXX_EMERGENCY_EH_ALLOC.
* crossconfig.m4: Check for secure_getenv.
* doc/Makefile.in: Regenerate.
* doc/xml/manual/configure.xml: Document new configure options.
* doc/xml/manual/evolution.xml: Document addition of tunables.
* doc/xml/manual/using_exceptions.xml: Document emergency
buffer and tunables.
* doc/html/*: Regenerate.
* include/Makefile.in: Regenerate.
* libsupc++/Makefile.am: Use EH_POOL_FLAGS.
* libsupc++/Makefile.in: Regenerate.
* libsupc++/eh_alloc.cc (EMERGENCY_OBJ_SIZE): Define in units
of sizeof(void*) not including the ABI's exception header.
(EMERGENCY_OBJ_COUNT): Define as target-independent calculation
based on word size.
(MAX_OBJ_COUNT): Define macro for upper limit on pool size.
(pool) [_GLIBCXX_EH_POOL_STATIC]: Use fixed-size buffer.
(pool::buffer_size_in_bytes): New static member function.
(pool::pool): Parse GLIBCXX_TUNABLES environment variable to set
pool size at runtime.
(pool::in_pool): Use std::less<void*> for total order.
(__freeres) [_GLIBCXX_EH_POOL_STATIC]: Do nothing.
(__cxa_free_exception, __cxa_free_dependent_exception): Add
[[unlikely]] attributes.
* po/Makefile.in: Regenerate.
* python/Makefile.in: Regenerate.
* src/Makefile.in: Regenerate.
* src/c++11/Makefile.in: Regenerate.
* src/c++17/Makefile.in: Regenerate.
* src/c++20/Makefile.in: Regenerate.
* src/c++98/Makefile.in: Regenerate.
* src/filesystem/Makefile.in: Regenerate.
* src/libbacktrace/Makefile.in: Regenerate.
* testsuite/Makefile.in: Regenerate.
Most libstdc++ configure args are of the form --enable-libstdcxx-xxx but
the option to build freestanding is --disable-hosted-libstdcxx. If you
accidentally type --disable-libstdcxx-hosted then it will be ignored.
This adds --disable-libstdcxx-hosted as an alias for the existing arg,
so it works whichever way you say it. If both args are used explicitly
and their values do not agree, configure fails with an error.
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_ENABLE_HOSTED): Add libstdcxx-hosted
enable arg as an alias for hosted-libstdcxx enable arg.
* configure: Regenerate.
This allows the library to switch to freestanding mode when compiling
with the -ffreestanding flag. This means you don't need a separate
libstdc++ build configured with --disable-hosted-libstdcxx in order to
compile for a freestanding environment.
The testsuite support files cannot be compiled for freestanding, so add
-fno-freestanding to override any -ffreestanding in the test flags.
libstdc++-v3/ChangeLog:
PR libstdc++/103626
* acinclude.m4 (GLIBCXX_ENABLE_HOSTED): Define _GLIBCXX_HOSTED
to __STDC_HOSTED__ for non-freestanding installations.
* configure: Regenerate.
* include/Makefile.am (${host_builddir}/c++config.h): Adjust
grep pattern.
* include/Makefile.in: Regenerate.
* testsuite/lib/libstdc++.exp (v3-build_support): Use
-fno-freestanding.
* testsuite/libstdc++-abi/abi.exp: Likewise.
The following patch is partially a workaround for bogus warnings
when the compiler isn't able to fold _M_disjunct call into constant
false, but also an optimization attempt - assuming _M_disjunct (__s)
is rare, the patch should shrink code size for the common case and
use library or for non-standard instantiations an out of line
function to handle the rare case.
2022-09-12 Jakub Jelinek <jakub@redhat.com>
PR tree-optimization/105329
* acinclude.m4 (libtool_VERSION): Change to 6:31:0.
* config/abi/pre/gnu.ver (GLIBCXX_3.4.21): Don't export
std::basic_string methods with name length of 15.
(GLIBCXX_3.4.31): Export std::basic_string::_M_replace_cold.
* testsuite/util/testsuite_abi.cc (check_version): Handle
GLIBCXX_3.4.31.
* include/bits/basic_string.h (std::basic_string::_M_replace_cold):
Declare.
* include/bits/basic_string.tcc (std::basic_string::_M_replace_cold):
Define and export even for C++20.
(std::basic_string::_M_replace): Use __builtin_expect, outline
the overlapping case to _M_replace_cold.
* configure: Regenerated.
rtems6.0 has fdopendir, and fcntl.h defines AT_FDCWD and declares
openat, but there's no openat in libc. Adjust dir-common.h to not
assume ::openat just because of AT_FDCWD.
for libstdc++-v3/ChangeLog
* acinclude.m4 (GLIBCXX_CHECK_FILESYSTEM_DEPS): Check for
openat.
* configure, config.h.in: Rebuilt.
* src/filesystem/dir-common.h (openat): Use ::openat if
_GLIBCXX_HAVE_OPENAT.
* src/filesystem/dir.cc (dir_and_pathname): Use dirfd if
_GLIBCXX_HAVE_OPENAT.
Using == instead of = causes a configuration error with dash as the
shell:
checking whether to build libbacktrace support... /home/devel/building/work/src/gcc-12-20220417/libstdc++-v3/configure: 77471: test: auto: unexpected operator
/home/devel/building/work/src/gcc-12-20220417/libstdc++-v3/configure: 77474: test: auto: unexpected operator
auto
This means we fail to change the value from "auto" to "no" and so this
test passes:
GLIBCXX_CONDITIONAL(ENABLE_BACKTRACE, [test "$enable_libstdcxx_backtrace" != no])
This leads to the libbacktrace directory being included in the build
without being configured properly, and bootstrap fails.
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_ENABLE_BACKTRACE): Fix shell operators.
* configure: Regenerate.
The RISC-V port requires libatomic to be linked in order to resolve
various atomic functions, which results in builds that have
"--with-libstdcxx-lock-policy=auto" defaulting to mutex-based locks.
Changing this to direct atomics breaks the ABI, this forces the auto
detection mutex-based atomics on RISC-V in order to avoid a silent ABI
break for users.
See Bug 84568 for more discussion. In the long run there may be a way
to get the higher-performance atomics without an ABI flag day, but
that's going to be a much more complicated operation. We don't even
have support for the inline atomics yet, but given that some folks have
been discussing hacks to make these libatomic routines appear implicitly
it seems prudent to just turn off the automatic detection for RISC-V.
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_ENABLE_LOCK_POLICY): Force auto to mutex
for RISC-V.
* configure: Regenerate.
