libstdc++-v3/ChangeLog:
PR libstdc++/104032
* include/std/spanstream (basic_spanbuf(basic_spanbuf&&)): Use
mem-initializer for _M_buf.
(basic_spanbuf::Operator=(basic_spanbuf&&)): Fix ill-formed
member access.
* testsuite/27_io/spanstream/2.cc: New test.
We can use the new from_chars implementation when long double and double
have the same representation.
libstdc++-v3/ChangeLog:
* src/c++17/floating_from_chars.cc (USE_STRTOD_FOR_FROM_CHARS):
Define macro for case where std::from_chars is implemented in
terms of strtod, strtof or strtold.
(buffer_resource, valid_fmt, find_end_of_float, pattern)
(from_chars_impl, make_result, reserve_string): Do not define
unless USE_STRTOD_FOR_FROM_CHARS is defined.
(from_chars): Define when at least one of USE_LIB_FAST_FLOAT and
USE_STRTOD_FOR_FROM_CHARS is defined, instead of
_GLIBCXX_HAVE_USELOCALE. Use fast_float for long double when it
is binary64.
I broke this unintentionally in r12-4259.
libstdc++-v3/ChangeLog:
PR libstdc++/104174
* include/bits/hashtable_policy.h (_Map_base): Add partial
specialization for maps with const key types.
* testsuite/23_containers/unordered_map/104174.cc: New test.
The non-atomic store that sets both reference counts to zero uses a
type-punned pointer, which has undefined behaviour. We could use memset
to write 8 bytes, but we don't actually need it to be a single store
anyway. No other thread can observe the values, that's why it's safe to
use non-atomic stores in the first place. So we can just set each count
to zero.
With -fstore-merging (which is enabled by default at -O2) GCC produces
the same code for this as for memset or the type punned store. Clang
does that store merging even at -O1.
libstdc++-v3/ChangeLog:
PR libstdc++/104019
* include/bits/shared_ptr_base.h (_Sp_counted_base<>::_M_release):
Set members to zero without type punning.
I changed the preprocessor condition from <= to < in r12-6574 which
meant the macro was not defined by <version> for C++17.
libstdc++-v3/ChangeLog:
* include/std/version (__cpp_lib_shared_ptr_arrays): Fix
condition for C++17 definition.
Clang doesn't support the __constinit extension that we use pre-C++20,
but it does have its own equivalent attribute that can be used instead.
This makes it a little easier to use Clang to build libstdc++ (which
isn't supported. but is sometimes attempted for esoteric targets).
libstdc++-v3/ChangeLog:
* src/c++11/cxx11-ios_failure.cc (__constinit): Define as
equivalent attribute for Clang.
* src/c++11/future.cc (__constinit): Likewise.
* src/c++11/system_error.cc (__constinit): Likewise.
* src/c++17/memory_resource.cc (__constinit): Likewise.
The MacOS linker warns about -L arguments that don't exist, which causes
all tests to fail for the defauly configuration (because libbacktrace
isn't built).
libstdc++-v3/ChangeLog:
* scripts/testsuite_flags.in: Only add src/filesystem/.libs and
src/libbacktrace/.libs to LDFLAGS if those directories exist.
The default is -gdwarf-5 now, so this is hurting rather than improving
things.
libstdc++-v3/ChangeLog:
* configure.ac (GLIBCXX_ENABLE_DEBUG_FLAGS): Remove -gdwarf-4
from default flags.
* configure: Regenerate.
This makes it possible to combine --enable-libstdcxx-debug with
--enable-libstdcxx-backtrace, by adding a rule to src/Makefile to copy
the backtrace-supported.h header into the src/debug/libbacktrace
directory.
Add libbacktrace path to testsuite flags so the tests can link without
having the library installed.
Also fix some warnings when running automake for the libbacktrace
makefile.
Use a per-library CPPFLAGS variable to fix:
src/libbacktrace/Makefile.am:38: warning: AM_CPPFLAGS multiply defined in condition TRUE ...
fragment.am:43: ... 'AM_CPPFLAGS' previously defined here
src/libbacktrace/Makefile.am:32: 'fragment.am' included from here
Create symlinks to the libbacktrace sources to fix:
src/libbacktrace/Makefile.am:55: warning: source file '../../../libbacktrace/atomic.c' is in a subdirectory,
src/libbacktrace/Makefile.am:55: but option 'subdir-objects' is disabled
libstdc++-v3/ChangeLog:
* scripts/testsuite_flags.in: Add src/libbacktrace/.libs to
linker search paths.
* src/Makefile.am: Fix src/debug/libbacktrace build.
* src/Makefile.in: Regenerate.
* src/libbacktrace/Makefile.am: Use per-library CPPFLAGS
variable. Use symlinks for the source files.
* src/libbacktrace/Makefile.in: Regenerate.
Use SFINAE magic to support: "It is unspecified whether math_errhandling
is a macro or an identifier with external linkage." [C Standard]
Signed-off-by: Matthias Kretz <m.kretz@gsi.de>
libstdc++-v3/ChangeLog:
* include/experimental/bits/simd.h (__floating_point_flags): Do
not rely on math_errhandling to expand to a constant expression.
This was deprecated in C++17, not C++14.
libstdc++-v3/ChangeLog:
* include/bits/stl_tempbuf.h (get_temporary_buffer): Change
_GLIBCXX14_DEPRECATED to _GLIBCXX17_DEPRECATED.
This function is no longer used since r12-6691 and can be removed.
libstdc++-v3/ChangeLog:
* include/bits/stl_pair.h (_PCC::_DeprConsPair): Remove unused
function.
This fixes an on AIX.
The lock function currently just spins, which should be changed to use
back-off, and maybe then _M_val.wait(__current) when supported.
libstdc++-v3/ChangeLog:
PR libstdc++/104101
* include/bits/shared_ptr_atomic.h (_Sp_atomic::_Atomic_count::lock):
Only use __thread_relax if __cpp_lib_atomic_wait is defined.
The new deleted constructors added by P2166R1 are a breaking change,
making previously valid code ill-formed in C++23. As a result, they
should only be defined for C++23 and not for C++11 and up.
libstdc++-v3/ChangeLog:
PR libstdc++/104099
* include/bits/basic_string.h (basic_string(nullptr_t)): Only
define for C++23.
(operator=(nullptr_t)): Likewise.
* include/bits/cow_string.h: Likewise.
* include/std/string_view (basic_string_view(nullptr_t)):
Likewise.
* testsuite/21_strings/basic_string/cons/char/nullptr.cc: Adjust
expected error. Add examples that become ill-formed in C++23.
* testsuite/21_strings/basic_string_view/cons/char/nonnull.cc:
Adjust expected errors.
* testsuite/21_strings/basic_string_view/cons/wchar_t/nonnull.cc:
Likewise.
We should not assume that std::iter_value_t etc. are defined
unconditionally for C++20 mode.
libstdc++-v3/ChangeLog:
PR libstdc++/104098
* include/bits/stl_iterator.h (reverse_iterator): Check
__cpp_lib_concepts instead of __cplusplus.
The deprecated non-standard std::pair constructors that allow
constructing std::pair<move-only-type, pointer-type> from an rvalue and
a literal zero where not sufficiently constrained. They were viable when
constructing std::pair<copyable-type, pointer-type>, and that case
should work fine using the standard constructors.
Replace the constraints on the non-standard constructors so they are
only viable in cases that should actually be ill-formed according to the
standard.
Also rename __null_ptr_constant to __zero_as_null_pointer_constant so it
matches the name of the -Wzero-as-null-pointer-constant warning. Also
make the text of the deprecated warning describe the problem in more
detail.
libstdc++-v3/ChangeLog:
PR libstdc++/101124
* include/bits/stl_pair.h (pair): Adjust constraints on
deprecated constructors accepting literal zero as null pointer
constant. Improve wording of deprecated attribute.
* testsuite/20_util/pair/cons/99957.cc: Check that deprecated
constructors do not cause ambiguities for copyable types.
This patch completes implementation of the C++20 proposal P0482R6 [1] by
adding declarations of std::c8rtomb() and std::mbrtoc8() in <cuchar> if
provided by the C library in <uchar.h>.
This patch addresses feedback provided in response to a previous patch
submission [2].
Autoconf changes determine if the C library declares c8rtomb and mbrtoc8
at global scope when uchar.h is included and compiled with either
-fchar8_t or -std=c++20. New _GLIBCXX_USE_UCHAR_C8RTOMB_MBRTOC8_FCHAR8_T
and _GLIBCXX_USE_UCHAR_C8RTOMB_MBRTOC8_CXX20 configuration macros
reflect the probe results. The <cuchar> header declares these functions
in the std namespace only if available and the _GLIBCXX_USE_CHAR8_T
configuration macro is defined (by default it is defined if the C++20
__cpp_char8_t feature test macro is defined)
Patches to glibc to implement c8rtomb and mbrtoc8 have been submitted [3].
New tests validate the presence of these declarations. The tests pass
trivially if the C library does not provide these functions. Otherwise
they ensure that the functions are declared when <cuchar> is included
and either -fchar8_t or -std=c++20 is enabled.
1]: WG21 P0482R6
"char8_t: A type for UTF-8 characters and strings (Revision 6)"
https://wg21.link/p0482r6
[2]: [PATCH] C++ P0482R6 char8_t: declare std::c8rtomb and std::mbrtoc8
if provided by the C library
https://gcc.gnu.org/pipermail/libstdc++/2021-June/052685.html
[3]: "C++20 P0482R6 and C2X N2653"
[Patch 0/3]:
https://sourceware.org/pipermail/libc-alpha/2022-January/135061.html
[Patch 1/3]:
https://sourceware.org/pipermail/libc-alpha/2022-January/135062.html
[Patch 2/3]:
https://sourceware.org/pipermail/libc-alpha/2022-January/135063.html
[Patch 3/3]:
https://sourceware.org/pipermail/libc-alpha/2022-January/135064.html
libstdc++-v3/ChangeLog:
* acinclude.m4: Define config macros if uchar.h provides
c8rtomb() and mbrtoc8().
* config.h.in: Regenerate.
* configure: Regenerate.
* include/c_compatibility/uchar.h (c8rtomb, mbrtoc8): Define.
* include/c_global/cuchar (c8rtomb, mbrtoc8): Likewise.
* include/c_std/cuchar (c8rtomb, mbrtoc8): Likewise.
* testsuite/21_strings/headers/cuchar/functions_std_cxx20.cc:
New test.
* testsuite/21_strings/headers/cuchar/functions_std_fchar8_t.cc:
New test.
This adds the C++23 <stdatomic.h> header, as proposed by P0943R6, for
compatibility with C code.
There are still some ABI differences between atomic_xxx in C and C++
std::atomic_xxx in C++, so this only provides source compatibility, not
binary compatibility.
libstdc++-v3/ChangeLog:
* include/Makefile.am: Install new header.
* include/Makefile.in: Regenerate.
* include/c_compatibility/stdatomic.h: New file.
* testsuite/29_atomics/headers/stdatomic.h/c_compat.cc: New test.
Instead of hardcoded preprocessor conditionals with explicit target
checks, just rely on the fact that __BYTE_ORDER__ is always defined by
GCC.
libstdc++-v3/ChangeLog:
PR libstdc++/104080
* src/c++17/fast_float/LOCAL_PATCHES: Update.
* src/c++17/fast_float/fast_float.h (FASTFLOAT_IS_BIG_ENDIAN):
Define in terms of __BYTE_ORDER__.
This makes our std::from_chars implementation use fast_float for decimal
parsing of binary32/64 numbers. For other floating-point formats we
still use the fallback implementation that goes through the strtod family
of functions.
libstdc++-v3/ChangeLog:
* src/c++17/floating_from_chars.cc: (USE_LIB_FAST_FLOAT):
Conditionally define, and use it to conditionally include
fast_float.
(from_chars): Use fast_float for float and double when
USE_LIB_FAST_FLOAT.
This changes fast_float's handling of overflow/underflow to be
consistent with the standard: instead of returning errc{} and setting
value to +-0 or +-infinity, just return errc::result_out_of_range and
don't modify value, as per [charconv.from.chars]/1.
libstdc++-v3/ChangeLog:
* src/c++17/fast_float/LOCAL_PATCHES: Update.
* src/c++17/fast_float/fast_float.h (from_chars_advanced): In
case of over/underflow, return errc::result_out_of_range and don't
modify 'value'.
This performs the following modifications to our local copy of fast_float
in order to make it more readily usable in our std::from_chars
implementation:
* Remove system #includes
* Replace stray call to assert
* Use the standard chars_format and from_chars_result types
libstdc++-v3/ChangeLog:
* src/c++17/fast_float/LOCAL_PATCHES: Update.
* src/c++17/fast_float/fast_float.h: Apply local modifications.
We're going to use the fast_float library[1] in our (compiled-in)
floating-point std::from_chars implementation for faster and more
portable parsing of binary32/64 decimal strings.
The single file fast_float.h is an amalgamation of the entire library,
which can be (re)generated with the amalgamate.py script (from the
fast_float repository) via the command
python3 ./script/amalgamate.py --license=MIT \
> $GCC_SRC/libstdc++-v3/c++17/fast_float/fast_float.h
The code has a GPL-compatible license.
[1]: https://github.com/fastfloat/fast_float
libstdc++-v3/ChangeLog:
* src/c++17/fast_float/LOCAL_PATCHES: New file.
* src/c++17/fast_float/MERGE: New file.
* src/c++17/fast_float/README.md: New file, copied from the
fast_float repository.
* src/c++17/fast_float/fast_float.h: New file, an amalgamation
of the fast_float library.
Signed-off-by: Patrick Palka <ppalka@redhat.com>
libstdc++-v3/ChangeLog:
* src/c++17/floating_from_chars.cc: Include <bit>.
(ascii_to_hexit, starts_with_ci): Conditionally define.
(__floating_from_chars_hex): Conditionally define.
(from_chars): Use __floating_from_chars_hex for
chars_format::hex parsing of binary32/64 float/double.
(testsuite/20_util/from_chars/7.cc): New test.
Add the <stacktrace> header and a new libstdc++_libbacktrace.a library
that provides the implementation. For now, the new library is only built
if --enable-libstdcxx-backtrace=yes is used. As with the Filesystem TS,
the new library is only provided as a static archive.
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_ENABLE_BACKTRACE): New macro.
* configure.ac: Use GLIBCXX_ENABLE_BACKTRACE.
* include/Makefile.am: Add new header.
* include/Makefile.in: Regenerate.
* include/std/stacktrace: New header.
* include/std/version (__cpp_lib_stacktrace): Define.
* Makefile.in: Regenerate.
* config.h.in: Regenerate.
* configure: Regenerate.
* doc/Makefile.in: Regenerate.
* libsupc++/Makefile.in: Regenerate.
* po/Makefile.in: Regenerate.
* python/Makefile.in: Regenerate.
* src/Makefile.am: 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.
* testsuite/Makefile.in: Regenerate.
* src/libbacktrace/Makefile.am: New file.
* src/libbacktrace/Makefile.in: New file.
* src/libbacktrace/backtrace-rename.h: New file.
* src/libbacktrace/backtrace-supported.h.in: New file.
* src/libbacktrace/config.h.in: New file.
* testsuite/lib/libstdc++.exp (check_effective_target_stacktrace):
New proc.
* testsuite/20_util/stacktrace/entry.cc: New test.
* testsuite/20_util/stacktrace/synopsis.cc: New test.
* testsuite/20_util/stacktrace/version.cc: New test.
Older glibc does not define math_errhandling with -ffast-math, in which
case floating-point exceptions are not used.
Signed-off-by: Matthias Kretz <m.kretz@gsi.de>
libstdc++-v3/ChangeLog:
* include/experimental/bits/simd.h (__floating_point_flags): Do
not rely on the presence of the math_errhandling macro.
This adds another piece of C++20, the std::atomic specializations for
std::shared_ptr and std::weak_ptr.
The new _Sp_atomic type mimics the structure of shared_ptr<T> and
weak_ptr<T>, holding a T* pointer (the one returned by get() on a
shared_ptr/weak ptr) and a _Sp_counted_base<>* pointer to the
ref-counted control block. For _Sp_atomic the low bit of the control
block pointer is used as a lock bit, to ensure only one thread will
access the object at a time. The pointer is actually stored as a
uintptr_t to avoid accidental dereferences of the pointer when unlocked
(which would be a race) or when locked (which would dereference the
wrong pointer value due to the low bit being set). To get a raw pointer
to the control block, the lock must be acquired. Converting between a
_Sp_atomic and a shared_ptr or weak_ptr requires manually adjusting the
T* and _Sp_counted_base<>* members of the shared/weak ptr, instead of
going through the public API. This must be done carefully to ensure that
any change in the number of owners is reflected in a ref-count update.
Co-authored-by: Thomas Rodgers <trodgers@redhat.com>
Signed-off-by: Thomas Rodgers <trodgers@redhat.com>
libstdc++-v3/ChangeLog:
* include/bits/shared_ptr_atomic.h (__cpp_lib_atomic_shared_ptr):
New macro.
(_Sp_atomic): New class template.
(atomic<shared_ptr<T>>, atomic<weak_ptr<T>>): New partial
specializations.
* include/bits/shared_ptr_base.h (__shared_count, __weak_count)
(__shared_ptr, __weak_ptr): Declare _Sp_atomic as a friend.
* include/std/version (__cpp_lib_atomic_shared_ptr): New macro.
* testsuite/20_util/shared_ptr/atomic/atomic_shared_ptr.cc: New
test.
* testsuite/20_util/weak_ptr/atomic_weak_ptr.cc: New test.
Explicitly support use of the stdx::simd implementation in situations
where the user links TUs that were compiled with different -m flags. In
general, this is always a (quasi) ODR violation for inline functions
because at least codegen may differ in important ways. However, in the
resulting executable only one (unspecified which one) of them might be
used. For simd we want to support users to compile code multiple times,
with different -m flags and have a runtime dispatch to the TU matching
the target CPU. But if internal functions are not inlined this may lead
to unexpected performance loss or execution of illegal instructions.
Therefore, inline functions that are not marked as always_inline must
use an additional template parameter somewhere in their name, to
disambiguate between the different -m translations.
Signed-off-by: Matthias Kretz <m.kretz@gsi.de>
libstdc++-v3/ChangeLog:
* include/experimental/bits/simd.h: Move feature detection bools
and add __have_avx512bitalg, __have_avx512vbmi2,
__have_avx512vbmi, __have_avx512ifma, __have_avx512cd,
__have_avx512vnni, __have_avx512vpopcntdq.
(__detail::__machine_flags): New function which returns a unique
uint64 depending on relevant -m and -f flags.
(__detail::__odr_helper): New type alias for either an anonymous
type or a type specialized with the __machine_flags number.
(_SimdIntOperators): Change template parameters from _Impl to
_Tp, _Abi because _Impl now has an __odr_helper parameter which
may be _OdrEnforcer from the anonymous namespace, which makes
for a bad base class.
(many): Either add __odr_helper template parameter or mark as
always_inline.
* include/experimental/bits/simd_detail.h: Add defines for
AVX512BITALG, AVX512VBMI2, AVX512VBMI, AVX512IFMA, AVX512CD,
AVX512VNNI, AVX512VPOPCNTDQ, and AVX512VP2INTERSECT.
* include/experimental/bits/simd_builtin.h: Add __odr_helper
template parameter or mark as always_inline.
* include/experimental/bits/simd_fixed_size.h: Ditto.
* include/experimental/bits/simd_math.h: Ditto.
* include/experimental/bits/simd_scalar.h: Ditto.
* include/experimental/bits/simd_neon.h: Add __odr_helper
template parameter.
* include/experimental/bits/simd_ppc.h: Ditto.
* include/experimental/bits/simd_x86.h: Ditto.
GCC Administrator
Jonathan Wakely
Matthias Kretz
Tom Honermann
Patrick Palka