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.
The test fails on Fedora 33+ because nl_NL locale got thousands
separator defined. Use one of ar_SA, bg_BG, bs_BA, pt_PT
or plain C locale instead.
2022-01-14 Uroš Bizjak <ubizjak@gmail.com>
libstdc++-v3/ChangeLog:
* testsuite/22_locale/numpunct/members/char/3.cc:
Require pt_PT locale instead of nl_NL.
(test02): Use pt_PT locale instead of nl_NL.
There are a lot of things in the C++ standard library which were
deprecated in C++11, and more in C++17. Some of them were removed after
deprecation and are no longer present in the standard at all. We have
not removed these from libstdc++ because keeping them as non-standard
extensions is conforming, and avoids gratuitously breaking user code,
and in some cases we need to keep using them to avoid ABI changes. But
we should at least give a warning for using them. That has not been done
previously because of the library's own uses of them (e.g. the
std::iterator class template used as a base class).
This adds deprecated attributes to the relevant components, and then
goes through the whole library to add diagnostic pragmas where needed to
suppress warnings about our internal uses of them. The tests are updated
to either expect the additional warnings, or to suppress them where we
aren't interested in them.
libstdc++-v3/ChangeLog:
PR libstdc++/91260
PR libstdc++/91383
PR libstdc++/95065
* include/backward/binders.h (bind1st, bind2nd): Add deprecated
attribute.
* include/bits/refwrap.h (_Maybe_unary_or_binary_function):
Disable deprecated warnings for base classes.
(_Reference_wrapper_base): Likewise.
* include/bits/shared_ptr_base.h (_Sp_owner_less): Likewise.
* include/bits/stl_bvector.h (_Bit_iterator_base): Likewise.
* include/bits/stl_function.h (unary_function, binary_function):
Add deprecated attribute.
(unary_negate, not1, binary_negate, not2, ptr_fun)
(pointer_to_unary_function, pointer_to_binary_function)
(mem_fun_t, const_mem_fun_t, mem_fun_ref_t, const_mem_fun_ref_t)
(mem_fun1_t, const_mem_fun1_t, mem_fun_ref1_t)
(const_mem_fun1_ref_t, mem_fun, mem_fun_ref): Add deprecated
attributes.
* include/bits/stl_iterator.h: Disable deprecated warnings for
std::iterator base classes.
* include/bits/stl_iterator_base_types.h (iterator): Add
deprecated attribute.
* include/bits/stl_map.h (map::value_compare): Disable
deprecated warnings for base class.
* include/bits/stl_multimap.h (multimap::value_compare):
Likewise.
* include/bits/stl_raw_storage_iter.h (raw_storage_iterator):
Add deprecated attribute.
* include/bits/stl_tempbuf.h (get_temporary_buffer): Likewise.
* include/bits/stream_iterator.h: Disable deprecated warnings.
* include/bits/streambuf_iterator.h: Likewise.
* include/ext/bitmap_allocator.h: Remove unary_function base
classes.
* include/ext/functional: Disable deprecated warnings.
* include/ext/rope: Likewise.
* include/ext/throw_allocator.h: Likewise.
* include/std/type_traits (result_of): Add deprecated attribute.
* include/tr1/functional: Disable deprecated warnings.
* include/tr1/functional_hash.h: Likewise.
* testsuite/20_util/function_objects/binders/1.cc: Add
-Wno-disable-deprecations.
* testsuite/20_util/function_objects/binders/3113.cc: Likewise.
* testsuite/20_util/function_objects/constexpr.cc: Add
dg-warning.
* testsuite/20_util/raw_storage_iterator/base.cc: Likewise.
* testsuite/20_util/raw_storage_iterator/dr2127.cc: Likewise.
* testsuite/20_util/raw_storage_iterator/requirements/base_classes.cc:
Likewise.
* testsuite/20_util/raw_storage_iterator/requirements/explicit_instantiation/1.cc:
Likewise.
* testsuite/20_util/raw_storage_iterator/requirements/typedefs.cc:
Likewise.
* testsuite/20_util/reference_wrapper/24803.cc:
Likewise.
* testsuite/20_util/reference_wrapper/typedefs.cc: Enable for
C++20 and check for absence of nested types.
* testsuite/20_util/shared_ptr/comparison/less.cc: Remove
std::binary_function base class.
* testsuite/20_util/temporary_buffer.cc: Add dg-warning.
* testsuite/21_strings/basic_string/cons/char/69092.cc: Remove
std::iterator base class.
* testsuite/24_iterators/back_insert_iterator/requirements/base_classes.cc:
Likewise.
* testsuite/24_iterators/front_insert_iterator/requirements/base_classes.cc:
Likewise.
* testsuite/24_iterators/insert_iterator/requirements/base_classes.cc:
Likewise.
* testsuite/24_iterators/istream_iterator/requirements/base_classes.cc:
Likewise.
* testsuite/24_iterators/istreambuf_iterator/92285.cc:
Likewise.
* testsuite/24_iterators/istreambuf_iterator/requirements/base_classes.cc:
Likewise.
* testsuite/24_iterators/ostream_iterator/requirements/base_classes.cc:
Likewise.
* testsuite/24_iterators/ostreambuf_iterator/requirements/base_classes.cc:
Likewise.
* testsuite/24_iterators/reverse_iterator/requirements/base_classes.cc:
Likewise.
* testsuite/25_algorithms/copy/34595.cc:
Likewise.
* testsuite/25_algorithms/minmax/3.cc: Remove std::binary_function
base class.
* testsuite/25_algorithms/all_of/requirements/explicit_instantiation/2.cc:
Disable deprecated warnings.
* testsuite/25_algorithms/all_of/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/any_of/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/any_of/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/copy_if/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/copy_if/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/count_if/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/count_if/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/find_end/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/find_end/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/find_first_of/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/find_first_of/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/find_if/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/find_if/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/find_if_not/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/find_if_not/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/for_each/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/for_each/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/is_partitioned/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/is_partitioned/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/is_permutation/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/is_permutation/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/none_of/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/none_of/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/partition/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/partition/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/partition_copy/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/partition_copy/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/partition_point/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/partition_point/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/random_shuffle/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/random_shuffle/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/remove_copy_if/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/remove_copy_if/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/remove_if/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/remove_if/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/replace_copy_if/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/replace_copy_if/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/replace_if/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/replace_if/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/search/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/search/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/search_n/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/search_n/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/stable_partition/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/stable_partition/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/25_algorithms/transform/requirements/explicit_instantiation/2.cc:
Likewise.
* testsuite/25_algorithms/transform/requirements/explicit_instantiation/pod.cc:
Likewise.
* testsuite/27_io/basic_filebuf/underflow/wchar_t/9178.cc: Add
dg-warning.
* testsuite/ext/pb_ds/example/priority_queue_erase_if.cc:
Likewise.
* testsuite/ext/pb_ds/example/priority_queue_split_join.cc:
Likewise.
* testsuite/tr1/3_function_objects/reference_wrapper/typedefs.cc:
Disable deprecated warnings.
* testsuite/tr1/6_containers/hash/requirements/base_classes.cc:
Likewise.
* testsuite/util/regression/trait/erase_if_fn.hpp: Remove
std::unary_function base classes.
* testsuite/util/testsuite_iterators.h (output_iterator_wrapper):
Remove std::iterator base classes.
This adds the overloads of std::make_shared and std::allocate_shared for
creating arrays, added to C++20 by P0674R1.
It also adds std::make_shared_for_overwrite, added to C++20 by P1020R1
(and renamed by P1973R1). The std::make_unique_for_overwite overloads
are already supported.
The original std::make_shared overload is changed to construct a
shared_ptr directly instead of calling std::allocate_shared. This
removes a function call at runtime, and avoids having to do overload
resolution for std::allocate_shared, now that there are five overloads
of it.
Allocating a shared array is done by a new __shared_count constructor.
An array is allocated with space for additional elements at the end and
an instance of new _Sp_counted_array class template is constructed in
that unused capacity.
The non-array form of std::make_shared_for_overwrite uses the same
__shared_count constructor as the original std::make_shared overload,
but a new partial specialization of _Sp_counted_ptr_inplace is selected
when the allocator's value_type is the new _Sp_overwrite_tag type. That
new partial specialization default-initializes its contained object and
destroys it with a destructor call rather than using the allocator.
Despite being C++20 features, this implementation only uses concepts
conditionally, with workarounds when they are not supported. This allows
it to work with older non-GCC compilers (Clang 9 and icc 2021). At some
point we can simplify the code by removing the workarounds.
libstdc++-v3/ChangeLog:
* include/bits/shared_ptr.h (__cpp_lib_shared_ptr_weak_type):
Correct type of macro value.
(shared_ptr): Add additional friend declarations.
(make_shared, allocate_shared): Constrain existing overloads and
remove static_assert.
* include/bits/shared_ptr_base.h (__cpp_lib_smart_ptr_for_overwrite):
New macro.
(_Sp_counted_ptr_inplace<T, Alloc, Lp>): New partial
specialization for use with make_shared_for_overwrite.
(__cpp_lib_shared_ptr_arrays): Update value for C++20.
(_Sp_counted_array_base): New class template.
(_Sp_counted_array): New class template.
(__shared_count(_Tp*&, const _Sp_counted_array_base&, _Init)):
New constructor for allocating shared arrays.
(__shared_ptr(const _Sp_counted_array_base&, _Init)): Likewise.
* include/std/version (__cpp_lib_shared_ptr_weak_type): Correct
type.
(__cpp_lib_shared_ptr_arrays): Update value for C++20.
(__cpp_lib_smart_ptr_for_overwrite): New macro.
* testsuite/20_util/shared_ptr/creation/99006.cc: Adjust
expected errors.
* testsuite/20_util/shared_ptr/creation/array.cc: New test.
* testsuite/20_util/shared_ptr/creation/overwrite.cc: New test.
* testsuite/20_util/shared_ptr/creation/version.cc: New test.
* testsuite/20_util/unique_ptr/creation/for_overwrite.cc: Check
feature test macro. Test non-trivial default-initialization.
When I added the std::allocator_traits<std::allocator<void>>
specialization it broke code like this:
std::allocate_shared<const int>(std::allocator<void>());
The problem is that allocator_traits<allocator<void>>::construct(a, p)
now uses std::_Construct(p), which only does a static_cast<void*>(p) and
so fails if the pointer has cv-quals.
This changes std::_Construct (and the related std::_Construct_novalue)
to use a C-style cast to (void*) which matches the effects of the
"voidify" helper in the C++20 standard.
libstdc++-v3/ChangeLog:
* include/bits/stl_construct.h (_Construct, _Construct_novalue):
Also cast away cv-qualifiers when converting pointer to void.
* testsuite/20_util/allocator/void.cc: Test construct function
with cv-qualified types.
This should have been done as part of the LWG 3574 changes.
libstdc++-v3/ChangeLog:
PR libstdc++/103992
* include/bits/stl_iterator.h (common_iterator): Use
std::construct_at instead of placement new.
* testsuite/24_iterators/common_iterator/1.cc: Check copy
construction is usable in constant expressions.
We currently crash when the floating-point to_chars overloads are passed
a precision value near INT_MAX, ultimately due to overflow in the bounds
checks that verify the output range is large enough.
The simplest portable fix seems to be to replace bounds checks of the form
A >= B + C (where B + C may overflow) with the otherwise equivalent check
A >= B && A - B >= C, which is the approach this patch takes.
Before we could do this in __floating_to_chars_hex, there we first need
to track the unbounded "excess" precision (i.e. the number of trailing
fractional digits in the output that are guaranteed to be '0') separately
from the bounded "effective" precision (i.e. the number of significant
fractional digits in the output), like we do in __f_t_c_precision.
PR libstdc++/103955
libstdc++-v3/ChangeLog:
* src/c++17/floating_to_chars.cc (__floating_to_chars_hex):
Track the excess precision separately from the effective
precision. Avoid overflow in bounds check by splitting it into
two checks.
(__floating_to_chars_precision): Avoid overflow in bounds checks
similarly.
* testsuite/20_util/to_chars/103955.cc: New test.
This C++20 header is also supposed to be present for freestanding.
libstdc++-v3/ChangeLog:
PR libstdc++/103726
* include/Makefile.am: Install <source_location> for
freestanding.
* include/Makefile.in: Regenerate.
* include/std/version (__cpp_lib_source_location): Define for
freestanding.
This was approved at the October 2021 plenary. We already have noexcept
in the other places the issue adds it in the spec.
libstdc++-v3/ChangeLog:
* include/std/ranges (ranges::lazy_split_view::_InnerIter::end()):
Add neoxcept (LWG 3593).
This LWG issue was approved at the October 2021 plenary and can be
implemented now that std::optional is fully constexpr.
libstdc++-v3/ChangeLog:
* include/std/ranges (ranges::__detail::__box): Add constexpr to
assignment operators (LWG 3572).
* testsuite/std/ranges/adaptors/filter.cc: Check assignment of a
view that uses copyable-box.
The standard says that <coroutine> should be present for freestanding.
That was intentionally left out of the initial implementation, but can
be done without much trouble. The header should be moved to libsupc++ at
some point in stage 1.
The standard also says that <coroutine> defines a std::hash
specialization, which was missing from our implementation. That's a
problem for freestanding (see LWG 3653) so only do that for hosted.
We can use concepts to constrain the __coroutine_traits_impl base class
when compiled with concepts enabled. In a pure C++20 implementation we
would not need that base class at all and could just use a constrained
partial specialization of coroutine_traits. But the absence of the
__coroutine_traits_impl<R, void> base would create an ABI difference
between the non-standard C++14/C++17 support for coroutines and the same
code compiled as C++20. If we drop support for <coroutine> pre-C++20 we
should revisit this.
libstdc++-v3/ChangeLog:
PR libstdc++/103726
* include/Makefile.am: Install <coroutine> for freestanding.
* include/Makefile.in: Regenerate.
* include/std/coroutine: Adjust headers and preprocessor
conditions.
(__coroutine_traits_impl): Use concepts when available.
[_GLIBCXX_HOSTED] (hash<coroutine_handle>): Define.
On the libsdc++ mailing list Lewis Hyatt pointed out the performance
overhead of using sputn in stream inserters, rather than writing
directly to the streambuf's put area:
https://gcc.gnu.org/pipermail/libstdc++/2021-July/052877.html
As Lewis noted, the standard explicitly requires a call to sputn for
inserting a std::basic_string_view or std::basic_string. But for
inserting single characters or null-terminated strings it is more vague,
and so we can improve performance by not using the __ostream_insert
function.
This is a minimal change that avoids __ostream_insert for single
characters. We can use the unformatted basic_ostream::put(charT)
function when we don't need the additional effects of a formatted output
function (i.e. padding and resetting the width). The put function will
insert into the buffer if possible, and only make a virtual call (to
overflow) if the buffer is full.
We could also avoid sputn when inserting null-terminated character
strings, but that would require using a new function for inserting
null-terminated strings, so the existing code using sputn is still used
for basic_string and basic_string_view. My preference is to leave that
for now, and try to improve the standard. We could either remove the
requirement to call sputn, or allow sputn to write directly to the
buffer instead of calling xsputn.
libstdc++-v3/ChangeLog:
* include/std/ostream (operator<<(basic_ostream&, charT)):
Use unformatted input if no padding is needed.
(operator<<(basic_ostream<char>&, char)): Likewise.
Clang has some bugs with destructors that use constraints to be
conditionally trivial, so disable the P2231R1 constexpr changes to
std::variant unless the compiler is GCC 12 or later.
If/when P2493R0 gets accepted and implemented by G++ we can remove the
__GNUC__ check and use __cpp_concepts >= 202002 instead.
libstdc++-v3/ChangeLog:
PR libstdc++/103891
* include/bits/c++config (_GLIBCXX_HAVE_COND_TRIVIAL_SPECIAL_MEMBERS):
Define.
* include/std/variant (__cpp_lib_variant): Only define C++20
value when the compiler is known to support conditionally
trivial destructors.
* include/std/version (__cpp_lib_variant): Likewise.
This library issue was approved in the October 2021 plenary.
libstdc++-v3/ChangeLog:
* include/bits/stl_iterator.h (common_iterator): Add constexpr
to all member functions (LWG 3574).
* testsuite/24_iterators/common_iterator/1.cc: Evaluate some
tests as constant expressions.
* testsuite/24_iterators/common_iterator/2.cc: Likewise.
glibc strptime passes around some state, what fields in struct tm have been
set and what needs to be finalized through possibly recursive calls, and
at the end performs various finalizations, like applying %p so that it
works for both %I %p and %p %I orders, or applying century so that both
%C %y and %y %C works, or computation of missing fields from others
(e.g. from %Y and %j one can compute tm_mon, tm_mday and tm_wday,
from %Y %U %w, %Y %W %w, %Y %U %a, or %Y %W %w one can compute
tm_mon, tm_mday, tm_yday or e.g. from %Y %m %d one can compute tm_wday
and tm_yday.
As the finalization is quite large and doesn't need to be a template
(doesn't depend on any iterators or char types), I've put it into libstdc++,
and left some padding in the state struct, so that perhaps in the future we
can track some more state without changing ABI.
Unfortunately, there is an ugly problem that the standard mandates that
get method calls the do_get virtual method and I don't see how we can
cary on any state in between those calls (even if we did an ABI change
for the facets, the methods are const, so that I think multiple threads
could use the same time_get objects and we couldn't store state in there).
There is a hack for that for GCC (seems to work with ICC too, doesn't work
with clang++) if the do_get method isn't overriden we can pass the state
around.
For both do_get_year and per IRC discussions also for %y, the behavior is
if 1-2 digits are parsed, the year is treated according to POSIX 2008 %y
rules (0-68 is 2000-2068, 69-99 is 1969-1999), if 3-4 digits are parsed,
it is treated as %Y.
2022-01-10 Jakub Jelinek <jakub@redhat.com>
PR libstdc++/77760
* include/bits/locale_facets_nonio.h (__time_get_state): New struct.
(time_get::_M_extract_via_format): Declare new method with
__time_get_state& as an extra argument.
* include/bits/locale_facets_nonio.tcc (_M_extract_via_format): Add
__state argument, set various fields in it while parsing. Handle %j,
%U, %w and %W, fix up handling of %y, %Y and %C, don't adjust tm_hour
for %p immediately. Add a wrapper around the method without the
__state argument for backwards compatibility.
(_M_extract_num): Remove all __len == 4 special cases.
(time_get::do_get_time, time_get::do_get_date, time_get::do_get): Zero
initialize __state, pass it to _M_extract_via_format and finalize it
at the end.
(do_get_year): For 1-2 digit parsed years, map 0-68 to 2000-2068,
69-99 to 1969-1999. For 3-4 digit parsed years use that as year.
(get): If do_get isn't overloaded from the locale_facets_nonio.tcc
version, don't call do_get but call _M_extract_via_format instead to
pass around state.
* config/abi/pre/gnu.ver (GLIBCXX_3.4.30): Export _M_extract_via_format
with extra __time_get_state and __time_get_state::_M_finalize_state.
* src/c++98/locale_facets.cc (is_leap, day_of_the_week,
day_of_the_year): New functions in anon namespace.
(mon_yday): New var in anon namespace.
(__time_get_state::_M_finalize_state): Define.
* testsuite/22_locale/time_get/get/char/4.cc: New test.
* testsuite/22_locale/time_get/get/wchar_t/4.cc: New test.
* testsuite/22_locale/time_get/get_year/char/1.cc (test01): Parse 197
as year 197AD instead of error.
* testsuite/22_locale/time_get/get_year/char/5.cc (test01): Parse 1 as
year 2001 instead of error.
* testsuite/22_locale/time_get/get_year/char/6.cc: New test.
* testsuite/22_locale/time_get/get_year/wchar_t/1.cc (test01): Parse
197 as year 197AD instead of error.
* testsuite/22_locale/time_get/get_year/wchar_t/5.cc (test01): Parse
1 as year 2001 instead of error.
* testsuite/22_locale/time_get/get_year/wchar_t/6.cc: New test.
This fixes the --disable-hosted-libstdcxx build so that it works with
--without-headers. Currently you need to also use --with-newlib, which
is confusing for users who aren't actually using newlib.
The AM_PROG_LIBTOOL checks are currently skipped for --with-newlib and
--with-avrlibc builds, with this change they are also skipped when using
--without-headers. It would be nice if using --disable-hosted-libstdcxx
automatically skipped those checks, but GLIBCXX_ENABLE_HOSTED comes too
late to make the AM_PROG_LIBTOOL checks depend on $is_hosted.
The checks for EOF, SEEK_CUR etc. cause the build to fail if there is no
<stdio.h> available. Unlike most headers, which get a HAVE_FOO_H macro,
<stdio.h> is in autoconf's default includes, so every check tries to
include it unconditionally. This change skips those checks for
freestanding builds.
Similarly, the checks for <stdint.h> types done by GCC_HEADER_STDINT try
to include <stdio.h> and fail for --without-headers builds. This change
skips the use of GCC_HEADER_STDINT for freestanding. We can probably
stop using GCC_HEADER_STDINT entirely, since only one file uses the
gstdint.h header that is generated, and that could easily be changed to
use <stdint.h> instead. That can wait for stage 1.
We also need to skip the GLIBCXX_CROSSCONFIG stage if --without-headers
was used, since we don't have any of the functions it deals with.
The end result of the changes above is that it should not be necessary
for a --disable-hosted-libstdcxx --without-headers build to also use
--with-newlib.
Finally, compile libsupc++ with -ffreestanding when --without-headers is
used, so that <stdint.h> will use <gcc-stdint.h> instead of expecting it
to come from libc.
libstdc++-v3/ChangeLog:
PR libstdc++/103866
* acinclude.m4 (GLIBCXX_COMPUTE_STDIO_INTEGER_CONSTANTS): Do
nothing for freestanding builds.
(GLIBCXX_ENABLE_HOSTED): Define FREESTANDING_FLAGS.
* configure.ac: Do not use AC_LIBTOOL_DLOPEN when configured
with --without-headers. Do not use GCC_HEADER_STDINT for
freestanding builds.
* libsupc++/Makefile.am (HOSTED_CXXFLAGS): Use -ffreestanding
for freestanding builds.
* configure: Regenerate.
* Makefile.in: Regenerate.
* doc/Makefile.in: Regenerate.
* include/Makefile.in: Regenerate.
* libsupc++/Makefile.in: Regenerate.
* 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.
* testsuite/Makefile.in: Regenerate.
When building a build!=host compiler, the just-built gcc can't be used
to build the target libstdc++ (because it is built for the host triplet,
not the build triplet). The top-level configure.ac sets up the build
flags for libstdc++ (and other "raw_cxx" libs) like this:
GCC_TARGET_TOOL(c++ for libstdc++, RAW_CXX_FOR_TARGET, CXX,
[gcc/xgcc -shared-libgcc -B$$r/$(HOST_SUBDIR)/gcc -nostdinc++ -L$$r/$(TARGET_SUBDIR)/libstdc++-v3/src -L$$r/$(TARGET_SUBDIR)/libstdc++-v3/src/.libs -L$$r/$(TARGET_SUBDIR)/libstdc++-v3/libsupc++/.libs],
c++)
The -nostdinc++ flag is only used for the IN-TREE-TOOL, i.e. when using
the just-built gcc/xgcc compiler. This means that the cross-compiler
used to build libstdc++ will add its own libstdc++ headers to the
include path. That results in the #include <cfenv> in
src/c++17/floating_to_chars.cc and src/c++17/floating_from_chars.cc
doing #include_next <fenv.h> and finding the libstdc++ fenv.h wrapper
from the host compiler. Because that has the same include guard as the
<fenv.h> in the libstdc++ we're trying to build, we never reach the
underlying <fenv.h> from libc. That results in several errors of the
form:
error: 'fenv_t' has not been declared in '::'
The most correct fix would be to add -nostdinc++ to the
RAW_CXX_FOR_TARGET variable in configure.ac, or the
RAW_CXX_TARGET_EXPORTS variable in Makefile.tpl.
Another solution would be to make the libstdc++ <fenv.h> wrapper use
_GLIBCXX_INCLUDE_NEXT_C_HEADERS like our <stdlib.h> and other C header
wrappers.
For now though, the simplest and safest solution is to just add
-nostdinc++ to the CXXFLAGS used for src/c++17/*.cc, which is what this
does.
libstdc++-v3/ChangeLog:
PR libstdc++/100017
* src/c++17/Makefile.am (AM_CXXFLAGS): Add -nostdinc++.
* src/c++17/Makefile.in: Regenerate.
This implements the proposed resolution of LWG 3088, so that x.merge(x)
is a no-op, consistent with std::list::merge.
Signed-off-by: Pavel I. Kryukov <pavel.kryukov@phystech.edu>
Co-authored-by: Jonathan Wakely <jwakely@redhat.com>
libstdc++-v3/ChangeLog:
PR libstdc++/103853
* include/bits/forward_list.tcc (forward_list::merge): Check for
self-merge.
* testsuite/23_containers/forward_list/operations/merge.cc: New test.
I think this code is valid but it fails with Clang, possibly due to
https://llvm.org/PR38882
Qualifying the names makes it work for all compilers.
libstdc++-v3/ChangeLog:
* include/bits/regex.h (basic_regex, match_results): Qualify
name in friend declaration, to work around Clang bug.
This test spawns thousands of threads and so times out if the tests are
run with a low timeout value and the machine is busy.
libstdc++-v3/ChangeLog:
* testsuite/ext/rope/pthread7-rope.cc: Add dg-timeout-factor.
This avoids a potential race condition if std::setlocale is used
concurrently with std::from_chars.
libstdc++-v3/ChangeLog:
PR libstdc++/103911
* include/std/charconv (__from_chars_alpha_to_num): Return
char instead of unsigned char. Change invalid return value to
127 instead of using numeric trait.
(__from_chars_alnum): Fix comment. Do not use std::isdigit.
Change type of variable to char.
When hasher is identified as slow and the number of elements is limited in the
container use a brute-force loop on those elements to look for a given key using
the key_equal functor. For the moment the default threshold to consider the
container as small is 20.
libstdc++-v3/ChangeLog:
PR libstdc++/68303
* include/bits/hashtable_policy.h
(_Hashtable_hash_traits<_Hash>): New.
(_Hash_code_base<>::_M_hash_code(const _Hash_node_value<>&)): New.
(_Hashtable_base<>::_M_key_equals): New.
(_Hashtable_base<>::_M_equals): Use latter.
(_Hashtable_base<>::_M_key_equals_tr): New.
(_Hashtable_base<>::_M_equals_tr): Use latter.
* include/bits/hashtable.h
(_Hashtable<>::__small_size_threshold()): New, use _Hashtable_hash_traits.
(_Hashtable<>::find): Loop through elements to look for key if size is lower
than __small_size_threshold().
(_Hashtable<>::_M_emplace(true_type, _Args&&...)): Likewise.
(_Hashtable<>::_M_insert_unique(_Kt&&, _Args&&, const _NodeGenerator&)): Likewise.
(_Hashtable<>::_M_compute_hash_code(const_iterator, const key_type&)): New.
(_Hashtable<>::_M_emplace(const_iterator, false_type, _Args&&...)): Use latter.
(_Hashtable<>::_M_find_before_node(const key_type&)): New.
(_Hashtable<>::_M_erase(true_type, const key_type&)): Use latter.
(_Hashtable<>::_M_erase(false_type, const key_type&)): Likewise.
* src/c++11/hashtable_c++0x.cc: Include <bits/functional_hash.h>.
* testsuite/util/testsuite_performance.h
(report_performance): Use 9 width to display memory.
* testsuite/performance/23_containers/insert_erase/unordered_small_size.cc:
New performance test case.
The C++17 basic_string(const T&, size_t, size_t) constructor is
overconstrained, so it can't be used for a NTBS and a temporary string
gets constructed (potentially allocating memory). There is no
corresponding constructor taking an NTBS, so no need to disambiguate
from it. Accepting an NTBS avoids the temporary (and potential
allocation) and is what the standard requires.
libstdc++-v3/ChangeLog:
PR libstdc++/103919
* include/bits/basic_string.h (basic_string(const T&, size_t, size_t)):
Relax constraints on string_view parameter.
* include/bits/cow_string.h (basic_string(const T&, size_t, size_t)):
Likewise.
* testsuite/21_strings/basic_string/cons/char/103919.cc: New test.
This feature is present in the C++23 draft.
With Jakub's recent front-end changes we can implement constexpr
equality by comparing the addresses of std::type_info objects. We do not
need string comparisons, because for constant evaluation cases we know
we aren't dealing with std::type_info objects defined in other
translation units.
The ARM EABI requires that the type_info::operator== function can be
defined out-of-line (and suggests that should be the default), but to be
a constexpr function it must be defined inline (at least for C++23
mode). To meet these conflicting requirements we make the inline version
of operator== call a new __equal function when called at runtime. That
is an alias for the non-inline definition of operator== defined in
libsupc++.
libstdc++-v3/ChangeLog:
* config/abi/pre/gnu.ver (GLIBCXX_3.4.30): Export new symbol for
ARM EABI.
* include/bits/c++config (_GLIBCXX23_CONSTEXPR): Define.
* include/std/version (__cpp_lib_constexpr_typeinfo): Define.
* libsupc++/tinfo.cc: Add #error to ensure non-inline definition
is emitted.
(type_info::__equal): Define alias symbol.
* libsupc++/typeinfo (type_info::before): Combine different
implementations into one.
(type_info::operator==): Likewise. Use address equality for
constant evaluation. Call __equal for targets that require the
definition to be non-inline.
* testsuite/18_support/type_info/constexpr.cc: New test.
In r12-3860 the error categories in <system_error> were made final and
immortal, but I missed the categories for <future> and <ios>. This makes
the same changes to those.
libstdc++-v3/ChangeLog:
* src/c++11/cxx11-ios_failure.cc (io_error_category): Define
class and virtual functions as 'final'.
(io_category_instance): Use constinit union to make the object
immortal.
* src/c++11/future.cc (future_error_category): Define class and
virtual functions as 'final'.
(future_category_instance): Use constinit union.
This helps visualize the NFA states in a std::regex. It probably isn't
very useful for users, but helps when working on the implementation.
libstdc++-v3/ChangeLog:
* python/libstdcxx/v6/printers.py (StdRegexStatePrinter): New
printer for std::regex NFA states.
We don't need a preprocessor condition to decide whether to use
placement new or std::construct_at, because std::_Construct already does
that.
libstdc++-v3/ChangeLog:
* include/bits/alloc_traits.h (allocator_traits<allocator<void>>):
Use std::_Construct for construct.
This moves the last two template parameters of __regex_algo_impl to be
runtime function parameters instead, so that we don't need four
different instantiations for the possible ways to call it. Most of the
function (and what it instantiates) is the same in all cases, so making
them compile-time choices doesn't really have much benefit.
Use 'if constexpr' for conditions that check template parameters, so
that when we do depend on a compile-time condition we only instantiate
what we need to.
libstdc++-v3/ChangeLog:
* include/bits/regex.h (__regex_algo_impl): Change __policy and
__match_mode template parameters to be function parameters.
(regex_match, regex_search): Pass policy and match mode as
function arguments.
* include/bits/regex.tcc (__regex_algo_impl): Change template
parameters to function parameters.
* include/bits/regex_compiler.h (_RegexTranslatorBase): Use
'if constexpr' for conditions using template parameters.
(_RegexTranslator): Likewise.
* include/bits/regex_executor.tcc (_Executor::_M_handle_accept):
Likewise.
* testsuite/util/testsuite_regex.h (regex_match_debug)
(regex_search_debug): Move template arguments to function
arguments.
The regex_match_debug testsuite helper doesn't compare the
std::match_results objects after a failed match, but it should do. The
standard says that the effects of a failed match on the match-results
are unspecified, except that [conditions testable by operator==]. So we
can check that the two sets of results compare equal even if the match
failed.
libstdc++-v3/ChangeLog:
* testsuite/util/testsuite_regex.h (regex_match_debug): Compare
results even if the match failed.
This replaces the vague "regex_error" for std::regex_error::what() with
a string that corresponds to the error_type enum passed to the
constructor. This allows us to remove many of the strings passed to
__throw_regex_error, because the default string is at least as good.
When a string argument to __throw_regex_error is kept it should add some
context-specific detail absent from the default string.
Also remove full stops (periods) from the end of those strings, to make
it easier to include them in logs and other output. I've left them
starting with an upper-case letter, which is consistent with strerror
output for (at least) Glibc, Solaris and BSD. I'm ambivalent whether
that's the right choice.
This also adds the missing noreturn attribute to __throw_regex_error.
libstdc++-v3/ChangeLog:
* include/bits/regex_compiler.tcc: Adjust all calls to
__throw_regex_error.
* include/bits/regex_error.h (__throw_regex_error): Add noreturn
attribute.
* include/bits/regex_scanner.tcc: Likewise.
* src/c++11/regex.cc (desc): New helper function.
(regex_error::regex_error(error_type)): Use desc to get a string
corresponding to the error code.
Prefer to overload __to_address to partially specialize std::pointer_traits because
std::pointer_traits would be mostly useless. Moreover partial specialization of
pointer_traits<__normal_iterator<P, C>> fails to rebind C, so you get incorrect types
like __normal_iterator<long*, vector<int>>. In the case of __gnu_debug::_Safe_iterator
the to_pointer method is impossible to implement correctly because we are missing
the parent container to associate the iterator to.
libstdc++-v3/ChangeLog:
* include/bits/stl_iterator.h
(std::pointer_traits<__gnu_cxx::__normal_iterator<>>): Remove.
(std::__to_address(const __gnu_cxx::__normal_iterator<>&)): New for C++11 to C++17.
* include/debug/safe_iterator.h
(std::__to_address(const __gnu_debug::_Safe_iterator<__gnu_cxx::__normal_iterator<>,
_Sequence>&)): New for C++11 to C++17.
* testsuite/24_iterators/normal_iterator/to_address.cc: Add check on std::vector::iterator
to validate both __gnu_cxx::__normal_iterator<> __to_address overload in normal mode and
__gnu_debug::_Safe_iterator in _GLIBCXX_DEBUG mode.
This patch uses the same not completely correct case insensitive comparisons
as used elsewhere in the same header. Proper comparisons that would handle
even multi-byte characters would be harder, but I don't see them implemented
in __ctype's methods.
2021-12-15 Jakub Jelinek <jakub@redhat.com>
PR libstdc++/71557
* include/bits/locale_facets_nonio.tcc (_M_extract_via_format):
Compare characters other than format specifiers and whitespace
case insensitively.
(_M_extract_name): Compare characters case insensitively.
* testsuite/22_locale/time_get/get/char/71557.cc: New test.
* testsuite/22_locale/time_get/get/wchar_t/71557.cc: New test.
This checks whether the locale data for en_HK includes %p and adjusts
the string being tested accordingly. To account for Jakub's fix to make
%I parse "12" as 0 instead of 12, we need to change the expected value
for the case where the locale format doesn't include %p. Also change the
time from 12:00:00 to 12:02:01 so we can tell if the minutes and seconds
get mixed up.
libstdc++-v3/ChangeLog:
PR libstdc++/103687
* testsuite/22_locale/time_get/get_date/wchar_t/4.cc: Restore
original locale before returning.
* testsuite/22_locale/time_get/get_time/char/2.cc: Check for %p
in locale's T_FMT and adjust accordingly.
* testsuite/22_locale/time_get/get_time/wchar_t/2.cc: Likewise.
std::regex currently allows invalid bracket ranges such as [\w-a] which
are only allowed by ECMAScript when in web browser compatibility mode.
It should be an error, because the start of the range is a character
class, not a single character. The current implementation of
_Compiler::_M_expression_term does not provide a way to reject this,
because we only remember a previous character, not whether we just
processed a character class (or collating symbol etc.)
This patch replaces the pair<bool, CharT> used to emulate
optional<CharT> with a custom class closer to pair<tribool,CharT>. That
allows us to track three states, so that we can tell when we've just
seen a character class.
With this additional state the code in _M_expression_term for processing
the _S_token_bracket_dash can be improved to correctly reject the [\w-a]
case, without regressing for valid cases such as [\w-] and [----].
libstdc++-v3/ChangeLog:
PR libstdc++/102447
* include/bits/regex_compiler.h (_Compiler::_BracketState): New
class.
(_Compiler::_BrackeyMatcher): New alias template.
(_Compiler::_M_expression_term): Change pair<bool, CharT>
parameter to _BracketState. Process first character for
ECMAScript syntax as well as POSIX.
* include/bits/regex_compiler.tcc
(_Compiler::_M_insert_bracket_matcher): Pass _BracketState.
(_Compiler::_M_expression_term): Use _BracketState to store
state between calls. Improve handling of dashes in ranges.
* testsuite/28_regex/algorithms/regex_match/cstring_bracket_01.cc:
Add more tests for ranges containing dashes. Check invalid
ranges with character class at the beginning.
This removes the __syntax_option and __match_flag enumeration types,
which are only used to define enumerators with successive values that
are then used to initialize the std::regex_constants global variables.
By defining enumerators in the syntax_option_type and match_flag_type
enumeration types with the correct values for the globals we get rid of
two useless enumeration types that just count from 0 to N, and we
improve the debugging experience. Because the enumeration types now have
enumerators defined, GDB will print values in terms of those enumerators
e.g.
$6 = (std::regex_constants::_S_ECMAScript | std::regex_constants::_S_multiline)
Previously this would have been shown as simply 0x810 because there were
no enumerators of that type.
This changes the type and value of enumerators such as _S_grep, but
users should never be referring to them directly anyway.
libstdc++-v3/ChangeLog:
* include/bits/regex_constants.h (__syntax_option, __match_flag):
Remove.
(syntax_option_type, match_flag_type): Define enumerators.
Use to initialize globals. Add constexpr to compound assignment
operators.
* include/bits/regex_error.h (error_type): Add comment.
* testsuite/28_regex/constants/constexpr.cc: Remove comment.
* testsuite/28_regex/constants/error_type.cc: Improve comment.
* testsuite/28_regex/constants/match_flag_type.cc: Check bitmask
requirements.
* testsuite/28_regex/constants/syntax_option_type.cc: Likewise.
libstdc++-v3/ChangeLog:
* include/bits/regex_compiler.tcc (_Compiler::_M_match_token):
Use reserved name for parameter.
* testsuite/17_intro/names.cc: Check "token".
The scripts/make_exports.pl script used for darwin only replaces '*'
wildcards in globs, it doesn't handle '?'. This means the recent changes
to std::__timepunct exports broke darwin.
Rather than use mangled names in the linker script, this adds support
for '?' to the perl script.
This also removes some unnecessary escaping of the replacement strings
in s// substitutions.
libstdc++-v3/ChangeLog:
* scripts/make_exports.pl: Replace '?' with '.' when turning
a glob into a regex.
Passing IncompleteType(&)[] to ranges::begin produces an error outside
the immediate context, which is fine for ranges::begin, but it means
that we fail to enforce the SFINAE-able constraints for ranges::size and
ranges::size. They should not be callable for any array of unknown
bound, whether the type is complete or not. Because we don't enforce
that in their constraints, we get a hard error when they try to use
ranges::begin.
This simply adds explicit checks for arrays of unknown bound to the
constraints for ranges::size and ranges::empty. We only need to check it
for the __sentinel_size and __eq_iter_empty concepts, because those are
the ones that are relevant to arrays, and which try to use
ranges::begin.
libstdc++-v3/ChangeLog:
* include/bits/ranges_base.h (ranges::size, ranges::empty): Add
explicit check for unbounded arrays before using ranges::begin.
* testsuite/std/ranges/access/empty.cc: Check handling of unbounded
arrays.
* testsuite/std/ranges/access/size.cc: Likewise.
The overload of std::regex_replace that takes a std::basic_string as the
fmt argument (for the replacement string) is implemented in terms of the
one taking a const C*, which uses std::char_traits to find the length.
That means it stops at a null character, even though the basic_string
might have additional characters beyond that.
Rather than duplicate the implementation of the const C* one for the
std::basic_string case, this moves that implementation to a new
__regex_replace function which takes a const C* and a length. Then both
the std::basic_string and const C* overloads can call that (with the
latter using char_traits to find the length to pass to the new
function).
libstdc++-v3/ChangeLog:
PR libstdc++/103664
* include/bits/regex.h (__regex_replace): Declare.
(regex_replace): Use it.
* include/bits/regex.tcc (__regex_replace): Replace regex_replace
definition with __regex_replace.
* testsuite/28_regex/algorithms/regex_replace/char/103664.cc: New test.
In the testcase for 103534 we get a warning about append leading to memcpy
of a very large number of bytes overflowing the buffer. This turns out to
be because we weren't calling _M_check_length for string append. Rather
than do that directly, let's go through the public pointer append that calls
it.
PR c++/103534
libstdc++-v3/ChangeLog:
* include/bits/basic_string.h (append (basic_string)): Call pointer
append instead of _M_append directly.
gcc/testsuite/ChangeLog:
* g++.dg/warn/Wstringop-overflow-8.C: New test.
This incremental patch adds std::time_get %r support (%p was added already
in the previous patch). The _M_am_fm_format method previously in the header
unfortunately had wrong arguments and so was useless, so the largest
complication in this patch is exporting a new symbol in the right symbol
version.
2021-12-10 Jakub Jelinek <jakub@redhat.com>
PR libstdc++/71367
* config/locale/dragonfly/time_members.cc (_M_initialize_timepunct):
Initialize "C" _M_am_pm_format to %I:%M:%S %p rather than empty
string.
* config/locale/gnu/time_members.cc (_M_initialize_timepunct):
Likewise.
* config/locale/generic/time_members.cc (_M_initialize_timepunct):
Likewise.
* include/bits/locale_facets_nonio.h (_M_am_pm_format): New method.
* include/bits/locale_facets_nonio.tcc (_M_extract_via_format): Handle
%r.
* config/abi/pre/gnu.ver (GLIBCXX_3.4.30): Export _M_am_pm_format
with const _CharT** argument, ensure it isn't exported in GLIBCXX_3.4.
* testsuite/22_locale/time_get/get/char/71367.cc: New test.
* testsuite/22_locale/time_get/get/wchar_t/71367.cc: New test.
The following patch is an attempt to fix various time_get related issues.
Sorry, it is long...
One of them is PR78714. It seems _M_extract_via_format has been written
with how strftime behaves in mind rather than how strptime behaves.
There is a significant difference between the two, for strftime %a and %A
behave differently etc., one emits an abbreviated name, the other full name.
For strptime both should behave the same and accept both the full or
abbreviated names. This needed large changes in _M_extract_name, which
was assuming the names are unique and names aren't prefixes of other names.
The _M_extract_name changes allow to deal with those cases. As can be
seen in the new testcase, e.g. for %b and english locales we need to
accept both Apr and April. If we see Apr in the input, the code looks
at whether there is end right after those 3 chars or if the next
character doesn't match characters in the longer names; in that case
it accepts the abbreviated name. Otherwise, if the input has Apri, it
commits to a longer name and fails if it isn't April. This behavior is
different from strptime, which for %bix and Aprix accepts it, but for
an input iterator I'm afraid we can't do better, we can't go back (peek
more than the current character).
Another case is that %d and %e in strptime should work the same, while
previously the code was hardcoding that %d would be 01 to 31 and %e
1 to 31 (with leading 0 replaced by space).
strptime POSIX 2009 documentation seems to suggest for numbers it should
accept up to the specified number of digits rather than exactly that number
of digits:
The pattern "[x,y]" indicates that the value shall fall within the range
given (both bounds being inclusive), and the maximum number of characters scanned
shall be the maximum required to represent any value in the range without leading
zeros.
so by my reading "1:" is valid for "%H:".
The glibc strptime implementation actually skips any amount of whitespace
in all the cases where a number is read, my current patch skips a single
space at the start of %d/%e but not the others, but doesn't subtract the
space length from the len characters.
One option would be to do the leading whitespace skipping in _M_extract_num
but take it into account how many digits can be read.
This matters for " 12:" and "%H:", but not for " 12:" and " %H:"
as in the latter case the space in the format string results in all the
whitespace at the start to be consumed.
Note, the allowing of a single digit rather than 2 changes a behavior in
other ways, e.g. when seeing 40 in a number for range [1, 31] we reject
it as before, but previously we'd keep *ret == '4' because it was assuming
it has to be 2 digits and 40 isn't valid, so we know error already on the
4, but now we accept the 4 as value and fail iff the next format string
doesn't match the 0.
Also, previously it wasn't really checking the number was in the right
range, it would accept 00 for [1, 31] numbers, or would accept 39.
Another thing is that %I was parsing 12 as tm_hour 12 rather than as tm_hour 0
like e.g. glibc does.
Another thing is that %t was matching a single tab and %n a single newline,
while strptime docs say it skips over whitespace (again, zero or more).
Another thing is that %p wasn't handled at all, I think this was the main
cause of
FAIL: 22_locale/time_get/get_time/char/2.cc execution test
FAIL: 22_locale/time_get/get_time/char/wrapped_env.cc execution test
FAIL: 22_locale/time_get/get_time/char/wrapped_locale.cc execution test
FAIL: 22_locale/time_get/get_time/wchar_t/2.cc execution test
FAIL: 22_locale/time_get/get_time/wchar_t/wrapped_env.cc execution test
FAIL: 22_locale/time_get/get_time/wchar_t/wrapped_locale.cc execution test
before this patch, because en_HK* locales do use %I and %p in it.
The patch handles %p only if it follows %I (i.e. when the hour is parsed
first), which is the more usual case (in glibc):
grep '%I' localedata/locales/* | grep '%I.*%p' | wc -l
282
grep '%I' localedata/locales/* | grep -v '%I.*%p' | wc -l
44
grep '%I' localedata/locales/* | grep -v '%p' | wc -l
17
The last case use %P instead of %p in t_fmt_ampm, not sure if that one
is never used by strptime because %P isn't handled by strptime.
Anyway, the right thing to handle even %p%I would be to pass some state
around through all the _M_extract_via_format calls like glibc passes
struct __strptime_state
{
unsigned int have_I : 1;
unsigned int have_wday : 1;
unsigned int have_yday : 1;
unsigned int have_mon : 1;
unsigned int have_mday : 1;
unsigned int have_uweek : 1;
unsigned int have_wweek : 1;
unsigned int is_pm : 1;
unsigned int want_century : 1;
unsigned int want_era : 1;
unsigned int want_xday : 1;
enum ptime_locale_status decided : 2;
signed char week_no;
signed char century;
int era_cnt;
} s;
around. That is for the %p case used like:
if (s.have_I && s.is_pm)
tm->tm_hour += 12;
during finalization, but handles tons of other cases which it is unclear
if libstdc++ needs or doesn't need to handle, e.g. strptime if one
specifies year and yday computes wday/mon/day from it, etc. basically for
the redundant fields computes them from other fields if those have been
parsed and are sufficient to determine it.
To do this we'd need to change ABI for the _M_extract_via_format,
though sure, we could add a wrapper around the new one with the old
arguments that would just use a dummy state. And we'd need a new
_M_whatever finalizer that would do those post parsing tweaks.
Also, %% wasn't handled.
For a whitespace in the strings there was inconsistent behavior,
_M_extract_via_format would require exactly that whitespace char (say
matching space, or matching tab), while the caller follows what
https://eel.is/c++draft/locale.time.get#members-8.5 says, that
when encountering whitespace it skips whitespace in the format and
then whitespace in the input if any. I've changed _M_extract_via_format
to skip whitespace in the input (looping over format isn't IMHO necessary,
because next iteration of the loop will handle that too).
Tested on x86_64-linux by make check-target-libstdc++-v3, ok for trunk
if it passes full bootstrap/regtest?
For the new 3.cc testcases, I have included hopefully correctly
corresponding C testcase using strptime in an attachment, and to the
extent where it can be compared (e.g. strptime on failure just
returns NULL, doesn't tell where it exactly stopped) I think the
only difference is that
str = "Novembur";
format = "%bembur";
ret = strptime (str, format, &time);
case where strptime accepts it but there is no way to do it with input
operator.
I admit I don't have libc++ or other STL libraries around to be able to
check how much the new 3.cc matches or disagrees with other implementations.
Now, the things not handled by this patch but which should be fixed (I
probably need to go back to compiler work) or at least looked at:
1) seems %j, %r, %U, %w and %W aren't handled (not sure if all of them
are already in POSIX 2009 or some are later)
2) I haven't touched the %y/%Y/%C and year handling stuff, that is
definitely not matching what POSIX 2009 says:
C All but the last two digits of the year {2}; leading zeros shall be permitted but shall not be required. A leading '+' or '−' character shall be permitted before
any leading zeros but shall not be required.
y The last two digits of the year. When format contains neither a C conversion specifier nor a Y conversion specifier, values in the range [69,99] shall refer to
years 1969 to 1999 inclusive and values in the range [00,68] shall refer to years 2000 to 2068 inclusive; leading zeros shall be permitted but shall not be re‐
quired. A leading '+' or '−' character shall be permitted before any leading zeros but shall not be required.
Note: It is expected that in a future version of this standard the default century inferred from a 2-digit year will change. (This would apply to all commands
accepting a 2-digit year as input.)
Y The full year {4}; leading zeros shall be permitted but shall not be required. A leading '+' or '−' character shall be permitted before any leading zeros but
shall not be required.
I've tried to avoid making changes to _M_extract_num for these as well
to keep current status quo (the __len == 4 cases). One thing is what
to do for things with %C %y and/or %Y in the formats, another thing
is what to do in the methods that directly perform _M_extract_num
for year
3) the above question what to do for leading whitespace of any numbers
being parsed
4) the %p%I issue mentioned above and generally what to do if we
pass state and have finalizers at the end of parsing
5) _M_extract_via_format is also inconsistent with its callers on handling
the non-whitespace characters in between format specifiers, the caller
follows https://eel.is/c++draft/locale.time.get#members-8.6 and does
case insensitive comparison:
// TODO real case-insensitive comparison
else if (__ctype.tolower(*__s) == __ctype.tolower(*__fmt) ||
__ctype.toupper(*__s) == __ctype.toupper(*__fmt))
while _M_extract_via_format only compares exact characters:
// Verify format and input match, extract and discard.
if (__format[__i] == *__beg)
++__beg;
(another question is if there is a better way how to do real
case-insensitive comparison of 2 characters and whether we e.g. need
to handle the Turkish i/İ and ı/I which have different number of bytes
in UTF-8)
6) _M_extract_name does something weird for case-sensitivity,
// NB: Some of the locale data is in the form of all lowercase
// names, and some is in the form of initially-capitalized
// names. Look for both.
if (__beg != __end)
and
if (__c == __names[__i1][0]
|| __c == __ctype.toupper(__names[__i1][0]))
for the first letter while just
__name[__pos] == *__beg
on all the following letters. strptime says:
In case a text string (such as the name of a day of the week or a month
name) is to be matched, the comparison is case insensitive.
so supposedly all the _M_extract_name comparisons should be case
insensitive.
2021-12-10 Jakub Jelinek <jakub@redhat.com>
PR libstdc++/78714
* include/bits/locale_facets_nonio.tcc (_M_extract_via_format):
Mention in function comment it interprets strptime format string
rather than strftime. Handle %a and %A the same by accepting both
full and abbreviated names. Similarly handle %h, %b and %B the same.
Handle %d and %e the same by accepting possibly optional single space
and 1 or 2 digits. For %I store tm_hour 0 instead of tm_hour 12. For
%t and %n skip any whitespace. Handle %p and %%. For whitespace in
the string skip any whitespace.
(_M_extract_num): For __len == 2 accept 1 or 2 digits rather than
always 2. Don't punt early if __value * __mult is larget than __max
or smaller than __min - __mult, instead punt if __value > __max.
At the end verify __value is in between __min and __max and punt
otherwise.
(_M_extract_name): Allow non-unique names or names which are prefixes
of other names. Don't recompute lengths of names for every character.
* testsuite/22_locale/time_get/get/char/3.cc: New test.
* testsuite/22_locale/time_get/get/wchar_t/3.cc: New test.
* testsuite/22_locale/time_get/get_date/char/12791.cc (test01): Use
62 instead 60 and expect 6 to be accepted and thus *ret01 == '2'.
* testsuite/22_locale/time_get/get_date/wchar_t/12791.cc (test01):
Similarly.
* testsuite/22_locale/time_get/get_time/char/2.cc (test02): Add " PM"
to the string.
* testsuite/22_locale/time_get/get_time/char/5.cc (test01): Expect
tm_hour 1 rather than 0.
* testsuite/22_locale/time_get/get_time/wchar_t/2.cc (test02): Add
" PM" to the string.
* testsuite/22_locale/time_get/get_time/wchar_t/5.cc (test01): Expect
tm_hour 1 rather than 0.
A mutex and condition variable is used for timed waits on atomics if
there is no "platform wait" (e.g. futex) supported. But the use of those
types wasn't guarded by the _GLIBCXX_HAS_GTHREADS macro, causing errors
for --disable-threads builds. This fix allows <atomic> to work on
targets with futexes but no gthreads.
libstdc++-v3/ChangeLog:
PR libstdc++/103638
* include/bits/atomic_timed_wait.h: Check _GLIBCXX_HAS_GTHREADS
before using std::mutex and std::__condvar.
If no OS function to sleep (e.g. nanosleep, usleep, Win32 Sleep etc.) is
available then configure defines the macro NO_SLEEP. But this will not
get prefixed with "_GLIBCXX_" because include/Makefile.am only does that
for macros beginning with "HAVE_". The configure script should define
_GLIBCXX_NO_SLEEP instead (which is what the code actually checks for).
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_ENABLE_LIBSTDCXX_TIME): Add _GLIBCXX_
prefix to NO_SLEEP macro.
* config.h.in: Regenerate.
* configure: Regenerate.
This was an oversight in the original commit adding wait/notify
to atomic<T>.
libstdc++-v3/ChangeLog:
PR libstdc++/102994
* include/bits/atomic_base.h (__atomic_base<_PTp*>::wait()):
Add const qualifier.
* include/std/atomic (atomic<_Tp*>::wait(), atomic_wait()):
Likewise.
* testsuite/29_atomics/atomic/wait_notify/102994.cc:
New test.
Since r11-1571 (c++: Refinements to "more constrained") was changed in
the front end, the following comment from stl_iterator.h stopped being
true:
// These extra overloads are not needed in C++20, because the ones above
// are constrained with a requires-clause and so overload resolution will
// prefer them to greedy unconstrained function templates.
The requires-clause is no longer considered when comparing unrelated
function templates. That means that the constrained operator== specified
in the standard is no longer more constrained than the pathological
comparison operators defined in the testsuite_greedy_ops.h header. This
was causing several tests to FAIL in C++20 mode:
FAIL: 23_containers/deque/types/1.cc (test for excess errors)
FAIL: 23_containers/vector/types/1.cc (test for excess errors)
FAIL: 24_iterators/move_iterator/greedy_ops.cc (test for excess errors)
FAIL: 24_iterators/normal_iterator/greedy_ops.cc (test for excess errors)
FAIL: 24_iterators/reverse_iterator/greedy_ops.cc (test for excess errors)
The solution is to restore some of the non-standard comparison operators
that are more specialized than the greedy operators in the testsuite.
libstdc++-v3/ChangeLog:
* include/bits/stl_iterator.h (operator==, operator<=>): Define
overloads for homogeneous specializations of reverse_iterator,
__normal_iterator and move_iterator.
This test no longer has additional errors for C++20 mode, so remove the
dg-error that is now failing, and the unnecessary dg-prune-output.
libstdc++-v3/ChangeLog:
* testsuite/20_util/scoped_allocator/69293_neg.cc: Remove
dg-error for c++20.
This allows std::make_exception_ptr to be used in a translation unit
compiled with -fno-exceptions. This works because the new implementation
added for PR 68297 doesn't need to throw or catch anything. The catch is
there to handle exceptions from the constructor of the exception object,
which we can assume won't happen in a -fno-exceptions TU and so use the
__catch macro instead. If the constructor does throw (because it's
defined in a different TU which was compiled with exceptions enabled)
then that exception will propagate to the make_exception_ptr caller.
That seems acceptable for a program that is trying to mix & match TUs
compiled with and without exceptions, and using types that throw when
constructed. That should be rare, and can't reasonably be expected to
have sensible behaviour.
This also enables the new implementation for targets that use a
non-standard calling convention for the exceptionDestructor callback
(specifically, mingw, which uses __thiscall). All we need to do is mark
the __dest_thunk function template with the right calling convention.
Finally, the useless no-op definition of make_exception_ptr (which is
only used if both RTTI and exceptions are disabled) is marked
always_inline, to ensure that the linker won't keep that definition and
discard the functional ones when both definitions of the function are
present in the link. An alternative would be to add the abi_tag
attribute to the useless definition, but making it always_inline should
work, and it's small enough to always be inlined reliably.
libstdc++-v3/ChangeLog:
PR libstdc++/85813
* libsupc++/exception_ptr.h (__dest_thunk): Add macro for
destructor calling convention.
(make_exception_ptr): Enable non-throwing implementation for
-fno-exceptions and for non-standard calling conventions. Use
always_inline attribute on the useless no-rtti no-exceptions
definition.
* testsuite/18_support/exception_ptr/64241.cc: Add -fno-rtti so
the no-op implementation is still used.
This restores support for std::make_exception_ptr<E&> and for using
std::exception_ptr in C++98.
Because the new non-throwing implementation needs to use std::decay to
handle references the original throwing implementation is used for
C++98.
We also need to change the typeid expression so it doesn't yield the
dynamic type when the function parameter is a reference to a polymorphic
type. Otherwise the new exception object could be caught by any handler
matching the dynamic type, even though the actual exception object is
only a copy of the base class, sliced to the static type.
libstdc++-v3/ChangeLog:
PR libstdc++/103630
* libsupc++/exception_ptr.h (exception_ptr): Fix exception
specifications on inline definitions.
(make_exception_ptr): Decay the template parameter. Use typeid
of the static type.
* testsuite/18_support/exception_ptr/103630.cc: New test.
This implements my P2467R0 proposal to support opening an fstream in
exclusive mode. The new constant is also supported pre-C++23 as
std::ios_base::__noreplace.
This proposal hasn't been approved for C++23 yet, but I am confident it
will be, as this is restoring a feture found in pre-ISO C++ iostreams
implementations (and still present in the MSVC library as _Noreplace).
If the proposal fails for C++23 we can remove the ios::noreplace
name and just keep ios::__noreplace as an extension.
libstdc++-v3/ChangeLog:
PR libstdc++/59769
* config/io/basic_file_stdio.cc (fopen_mode): Add support for
exclusive mode.
* include/bits/ios_base.h (_S_noreplace): Define new enumerator.
(ios_base::__noreplace): Define.
(ios_base::noreplace): Define for C++23.
* include/std/version (__cpp_lib_ios_noreplace): Define.
* testsuite/27_io/basic_ofstream/open/char/noreplace.cc: New test.
* testsuite/27_io/basic_ofstream/open/wchar_t/noreplace.cc: New test.
std::condition_variable::wait(unique_lock<mutex>&) is incorrectly marked
noexcept, which means that the __forced_unwind exception used by NPTL
cancellation will terminate the process. It should allow exceptions to
pass through, so that a thread can be cleanly cancelled when waiting on
a condition variable.
The new behaviour is exported as a new version of the symbol, to avoid
an ABI break for existing code linked to the non-throwing definition of
the function. Code linked against older releases will have a reference
to the @GLIBCXX_3.4.11 version, andcode compiled against the new
libstdc++ will get a reference to the @@GLIBCXX_3.4.30 version.
libstdc++-v3/ChangeLog:
PR libstdc++/103382
* config/abi/pre/gnu.ver (GLIBCXX_3.4.11): Do not export old
symbol if .symver renaming is supported.
(GLIBCXX_3.4.30): Export new symbol if .symver renaming is
supported.
* doc/xml/manual/evolution.xml: Document change.
* doc/html/manual/api.html: Regenerate.
* include/bits/std_mutex.h (__condvar::wait, __condvar::wait_until):
Remove noexcept.
* include/std/condition_variable (condition_variable::wait):
Likewise.
* src/c++11/condition_variable.cc (condition_variable::wait):
Likewise.
* src/c++11/compatibility-condvar.cc (__nothrow_wait_cv::wait):
Define nothrow wrapper around std::condition_variable::wait and
export the old symbol as an alias to it.
* testsuite/30_threads/condition_variable/members/103382.cc: New test.
Inserting a pair<Key, Value> into a map<Key, Value> will allocate a new
node and construct a pair<const Key, Value> in the node, then check if
the Key is already present in the map. That is because pair<Key, Value>
is not the same type as the map's value_type. But it only differs in the
const-qualification on the Key, and so we should be able to do the
lookup directly, without allocating a new node. This avoids allocating
and then deallocating a node for the case where the key is already found
and nothing gets inserted.
We can take this optimization further and lookup the key directly for a
pair<Key, X>, pair<const Key, X>, pair<Key&, X> etc. for any X. A strict
reading of the standard says we can only do this when we know the
allocator won't do anything funky with the value when constructing a
pair<const Key, Value> from a slightly different type. Inserting that
type only requires the value_type to be Cpp17EmplaceInsertable into the
container, and that doesn't have any requirement that the value is
unchanged (unlike Cpp17CopyInsertable and Cpp17MoveInsertable). For that
reason, the optimization is only done for maps using std::allocator.
A similar optimization can be done for map.emplace(key, value) where the
first argument is similar to the key_type and so can be looked up
without allocating a new node and constructing a key_type.
Finally, both of the insert and emplace cases can use the same
optimization when key_type is a scalar type and some other scalar is
being passed as the insert/emplace argument. Converting from one scalar
type to another won't have surprising value-altering behaviour, and has
no side effects (unlike e.g. constructing a std::string from a const
char* argument, which might allocate).
We don't need to do this for std::multimap, because we always insert the
new node even if the key is already present. So there's no benefit to
doing the lookup before allocating the new node.
libstdc++-v3/ChangeLog:
PR libstdc++/92300
* include/bits/stl_map.h (insert(Pair&&), emplace(Args&&...)):
Check whether the arguments can be looked up directly without
constructing a temporary node first.
* include/bits/stl_pair.h (__is_pair): Move to here, from ...
* include/bits/uses_allocator_args.h (__is_pair): ... here.
* testsuite/23_containers/map/modifiers/emplace/92300.cc: New test.
* testsuite/23_containers/map/modifiers/insert/92300.cc: New test.
When non-const references, pointers or iterators are obtained to the
contents of a COW std::basic_string, the implementation has to assume it
could result in a write to the contents. If the string was previously
shared, it does the "copy-on-write" step of creating a new copy of the
data that is not shared by another object. It also marks the string as
"leaked", so that no future copies of it will share ownership either.
However, if the string is empty then the only character in the sequence
is the terminating null, and modifying that is undefined behaviour. This
means that non-const references/pointers/iterators to an empty string
are effectively const. Since no direct modification is possible, there
is no need to "leak" the string, it can be safely shared with other
objects. This avoids unnecessary allocations to create new copies of
empty strings that can't be modified anyway.
We already did this optimization for strings that share ownership of the
static _S_empty_rep() object, but not for strings that have non-zero
capacity, and not for fully-dynamic-strings (where the _S_empty_rep()
object is never used).
With this change we avoid two allocations in the return statement:
std::string s;
s.reserve(1); // allocate
std::string s2 = s;
std::string s3 = s;
return s[0] + s2[0] + s3[0]; // leak+allocate twice
libstdc++-v3/ChangeLog:
* include/bits/cow_string.h (basic_string::_M_leak_hard): Do not
reallocate an empty string.
These warnings are triggered by perfectly valid code using std::string.
They're particularly bad when --enable-fully-dynamic-string is used,
because even std::string().begin() will give a warning.
Use pragmas to stop the troublesome warnings for copies done by
std::char_traits.
libstdc++-v3/ChangeLog:
PR libstdc++/103332
PR libstdc++/102958
PR libstdc++/103483
* include/bits/char_traits.h: Suppress stringop and array-bounds
warnings.
The possible base classes of std::allocator are new_allocator and
malloc_allocator, which both cause a non-reserved name to be declared in
every program that includes the definition of std::allocator. This is
non-conforming.
This change replaces __gnu_cxx::new_allocator with std::__new_allocator
which is identical except for using a reserved name. The non-standard
extension __gnu_cxx::new_allocator is preserved as a thin wrapper over
std::__new_allocator. There is no problem with the extension using a
non-reserved name now that it's not included by default in other
headers.
The same change could be done to __gnu_cxx::malloc_allocator but as it's
not the default configuration it can wait.
libstdc++-v3/ChangeLog:
PR libstdc++/64135
* config/allocator/new_allocator_base.h: Include
<bits/new_allocator.h> instead of <ext/new_allocator.h>.
(__allocator_base): Use std::__new_allocator instead of
__gnu_cxx::new_allocator.
* doc/xml/manual/allocator.xml: Document new default base class
for std::allocator.
* doc/xml/manual/evolution.xml: Likewise.
* doc/html/*: Regenerate.
* include/Makefile.am: Add bits/new_allocator.h.
* include/Makefile.in: Regenerate.
* include/experimental/memory_resource (new_delete_resource):
Use std::__new_allocator instead of __gnu_cxx::new_allocator.
* include/ext/new_allocator.h (new_allocator): Derive from
std::__new_allocator. Move implementation to ...
* include/bits/new_allocator.h: New file.
* testsuite/20_util/allocator/64135.cc: New test.
The check for _Atomic_word being 32-bit is just a normal runtime
condition for C++11 and C++14, because it doesn't use if-constexpr. That
means the 1LL << (CHAR_BIT * sizeof(_Atomic_word)) expression expands to
1LL << 64 on Solaris, which is ill-formed.
This adds another indirection so that the shift width is zero if the
code is unreachable.
libstdc++-v3/ChangeLog:
* include/bits/shared_ptr_base.h (_Sp_counted_base::_M_release()):
Make shift width conditional on __double_word condition.
This rewrites _Sp_counted_base::_M_release to skip the two atomic
instructions that decrement each of the use count and the weak count
when both are 1.
Benefits: Save the cost of the last atomic decrements of each of the use
count and the weak count in _Sp_counted_base. Atomic instructions are
significantly slower than regular loads and stores across major
architectures.
How current code works: _M_release() atomically decrements the use
count, checks if it was 1, if so calls _M_dispose(), atomically
decrements the weak count, checks if it was 1, and if so calls
_M_destroy().
How the proposed algorithm works: _M_release() loads both use count and
weak count together atomically (assuming suitable alignment, discussed
later), checks if the value corresponds to a 0x1 value in the individual
count members, and if so calls _M_dispose() and _M_destroy().
Otherwise, it follows the original algorithm.
Why it works: When the current thread executing _M_release() finds each
of the counts is equal to 1, then no other threads could possibly hold
use or weak references to this control block. That is, no other threads
could possibly access the counts or the protected object.
There are two crucial high-level issues that I'd like to point out first:
- Atomicity of access to the counts together
- Proper alignment of the counts together
The patch is intended to apply the proposed algorithm only to the case of
64-bit mode, 4-byte counts, and 8-byte aligned _Sp_counted_base.
** Atomicity **
- The proposed algorithm depends on the mutual atomicity among 8-byte
atomic operations and 4-byte atomic operations on each of the 4-byte halves
of the 8-byte aligned 8-byte block.
- The standard does not guarantee atomicity of 8-byte operations on a pair
of 8-byte aligned 4-byte objects.
- To my knowledge this works in practice on systems that guarantee native
implementation of 4-byte and 8-byte atomic operations.
- __atomic_always_lock_free is used to check for native atomic operations.
** Alignment **
- _Sp_counted_base is an internal base class, with a virtual destructor,
so it has a vptr at the beginning of the class, and will be aligned to
alignof(void*) i.e. 8 bytes.
- The first members of the class are the 4-byte use count and 4-byte
weak count, which will occupy 8 contiguous bytes immediately after the
vptr, i.e. they form an 8-byte aligned 8 byte range.
Other points:
- The proposed algorithm can interact correctly with the current algorithm.
That is, multiple threads using different versions of the code with and
without the patch operating on the same objects should always interact
correctly. The intent for the patch is to be ABI compatible with the
current implementation.
- The proposed patch involves a performance trade-off between saving the
costs of atomic instructions when the counts are both 1 vs adding the cost
of loading the 8-byte combined counts and comparison with {0x1, 0x1}.
- I noticed a big difference between the code generated by GCC vs LLVM. GCC
seems to generate noticeably more code and what seems to be redundant null
checks and branches.
- The patch has been in use (built using LLVM) in a large environment for
many months. The performance gains outweigh the losses (roughly 10 to 1)
across a large variety of workloads.
Signed-off-by: Jonathan Wakely <jwakely@redhat.com>
Co-authored-by: Jonathan Wakely <jwakely@redhat.com>
libstdc++-v3/ChangeLog:
* include/bits/c++config (_GLIBCXX_TSAN): Define macro
indicating that TSan is in use.
* include/bits/shared_ptr_base.h (_Sp_counted_base::_M_release):
Replace definition in primary template with explicit
specializations for _S_mutex and _S_atomic policies.
(_Sp_counted_base<_S_mutex>::_M_release): New specialization.
(_Sp_counted_base<_S_atomic>::_M_release): New specialization,
using a single atomic load to access both reference counts at
once.
(_Sp_counted_base::_M_release_last_use): New member function.
Newlib has reverted the commit that caused us to require a
workaround. As such we can now revert the workaround.
This reverts commit 0e510ab534.
libstdc++-v3/ChangeLog:
PR libstdc++/103305
* config/os/newlib/ctype_base.h (upper, lower, alpha, digit, xdigit,
space, print, graph, cntrl, punct, alnum, blank): Revert.
This fixes a -Wuninitialized warning for std::cmatch m1, m2; m1=m2;
Also name the template parameters in the forward declaration, to get rid
of the <template-parameter-1-1> noise in diagnostics.
libstdc++-v3/ChangeLog:
PR libstdc++/103549
* include/bits/regex.h (match_results): Give names to template
parameters in first declaration.
(match_results::_M_begin): Add default member-initializer.
This introduces a new RAII type to simplify the emplace members which
currently use try-catch blocks to deallocate a node if an exception is
thrown by the comparisons done during insertion. The new type is created
on the stack and manages the allocation of a new node and deallocates it
in the destructor if it wasn't inserted into the tree. It also provides
helper functions for doing the insertion, releasing ownership of the
node to the tree.
Also, we don't need to use long qualified names if we put the return
type after the nested-name-specifier.
libstdc++-v3/ChangeLog:
* include/bits/stl_tree.h (_Rb_tree::_Auto_node): Define new
RAII helper for creating and inserting new nodes.
(_Rb_tree::_M_insert_node): Use trailing-return-type to simplify
out-of-line definition.
(_Rb_tree::_M_insert_lower_node): Likewise.
(_Rb_tree::_M_insert_equal_lower_node): Likewise.
(_Rb_tree::_M_emplace_unique): Likewise. Use _Auto_node.
(_Rb_tree::_M_emplace_equal): Likewise.
(_Rb_tree::_M_emplace_hint_unique): Likewise.
(_Rb_tree::_M_emplace_hint_equal): Likewise.
The move constructor for the fully-dynamic std::basic_string was not
noexcept until recently, so the std::logic_error and std::runtime_error
move constructors were defined to make non-throwing copies of their
string members, instead of potentially-throwing moves.
Now that move construction is always noexecpt, the exception classes can
always move the string. The fully-dynamic string move assignment was
always noexcept, so I don't know why I special-cased the move assignment
operators of the exception classes. That can be changed too.
libstdc++-v3/ChangeLog:
* src/c++11/cow-stdexcept.cc [_GLIBCXX_FULY_DYNAMIC_STRING]
(logic_error, runtime_error): Remove custom definitions.
The bitmap_allocator, __mt_alloc and __pool_alloc extensions are no
longer suitable for use as the base class of std::allocator, because
they have not been updated to meet the C++20 requirements. There is a
patch attached to PR 103340 which addresses that, but more work would be
needed to solve the linking errors that occur when the library is
configured to use them.
Using --enable-libstdcxx-allocator=bitmap wouldn't even bootstrap for
the past few years, and I can't find any gcc-testresults reports using
any of these allocators. This patch removes the configure option to use
these as the std::allocator base class. The allocators are still in the
tree and can be used directly, you just can't configure the library to
use one of them as the base class of std::allocator.
libstdc++-v3/ChangeLog:
PR libstdc++/103340
PR libstdc++/103400
PR libstdc++/103381
* acinclude.m4 (GLIBCXX_ENABLE_ALLOCATOR): Remove mt, bitmap
and pool options.
* configure: Regenerate.
* config/allocator/bitmap_allocator_base.h: Removed.
* config/allocator/mt_allocator_base.h: Removed.
* config/allocator/pool_allocator_base.h: Removed.
* doc/xml/manual/allocator.xml: Update.
* doc/xml/manual/configure.xml: Update.
* doc/xml/manual/evolution.xml: Document removal.
* doc/xml/manual/mt_allocator.xml: Editorial tweaks.
* doc/html/manual/*: Regenerate.
The relaxed load is already optimal, checking the __single_threaded
global before doing a non-atomic load isn't an optimization.
libstdc++-v3/ChangeLog:
* include/bits/cow_string.h (basic_string::_M_is_leaked()):
Revert change to check __is_single_threaded() before using
atomic load.
If the allocator-extended move constructor move-constructs each element
into the new container, the contents of the old container are left in
moved-from states. We cannot know if those states preserve the
container's ordering and uniqueness guarantees, so just erase all
moved-from elements.
libstdc++-v3/ChangeLog:
PR libstdc++/103501
* include/bits/stl_tree.h (_Rb_tree(_Rb_tree&&, false_type)):
Clear container if elements have been moved-from.
* testsuite/23_containers/map/allocator/move_cons.cc: Expect
moved-from container to be empty.
* testsuite/23_containers/multimap/allocator/move_cons.cc:
Likewise.
* testsuite/23_containers/multiset/allocator/103501.cc: New test.
* testsuite/23_containers/set/allocator/103501.cc: New test.
This adds std::__is_constant_evaluated() as a C++11 wrapper for
__builtin_is_constant_evaluated, but just returning false if the
built-in isn't supported by the compiler. This allows us to use it
throughout the library without checking __has_builtin every time.
Some uses in std::vector and std::string can only be constexpr when the
std::is_constant_evaluated() function actually works, so we might as
well guard them with a relevant macro and call that function directly,
rather than the built-in or std::__is_constant_evaluated().
The remaining checks of the __cpp_lib_is_constant_evaluated macro could
now be replaced by checking __cplusplus >= 202002 instead, but there's
no practical difference. We still need some kind of preprocessor check
there anyway.
libstdc++-v3/ChangeLog:
* doc/doxygen/user.cfg.in (PREDEFINED): Change macro name.
* include/bits/allocator.h (allocate, deallocate): Use
std::__is_constant_evaluated() unconditionally, instead of
checking whether std::is_constant_evaluated() (or the built-in)
can be used.
* include/bits/basic_string.h: Check new macro. call
std::is_constant_evaluated() directly in C++20-only code that is
guarded by a suitable macro.
* include/bits/basic_string.tcc: Likewise.
* include/bits/c++config (__is_constant_evaluated): Define.
(_GLIBCXX_HAVE_BUILTIN_IS_CONSTANT_EVALUATED): Replace with ...
(_GLIBCXX_HAVE_IS_CONSTANT_EVALUATED): New macro.
* include/bits/char_traits.h (char_traits): Replace conditional
calls to std::is_constant_evaluated with unconditional calls to
std::__is_constant_evaluated.
* include/bits/cow_string.h: Use new macro.
* include/bits/ranges_algobase.h (__copy_or_move): Replace
conditional calls to std::is_constant_evaluated with unconditional
calls to std::__is_constant_evaluated.
(__copy_or_move_backward, __fill_n_fn): Likewise.
* include/bits/ranges_cmp.h (ranges::less): Likewise.
* include/bits/stl_algobase.h (lexicographical_compare_three_way):
Likewise.
* include/bits/stl_bvector.h: Call std::is_constant_evaluated
directly in C++20-only code that is guarded by a suitable macro.
* include/bits/stl_construct.h (_Construct, _Destroy, _Destroy_n):
Replace is_constant_evaluated with __is_constant_evaluated.
* include/bits/stl_function.h (greater, less, greater_equal)
(less_equal): Replace __builtin_is_constant_evaluated and
__builtin_constant_p with __is_constant_evaluated.
* include/bits/stl_vector.h: Call std::is_constant_evaluated()
in C++20-only code.
* include/debug/helper_functions.h (__check_singular): Use
__is_constant_evaluated instead of built-in, or remove check
entirely.
* include/std/array (operator<=>): Use __is_constant_evaluated
unconditionally.
* include/std/bit (__bit_ceil): Likewise.
* include/std/type_traits (is_constant_evaluated): Define using
'if consteval' if possible.
* include/std/version: Use new macro.
* libsupc++/compare: Use __is_constant_evaluated instead of
__builtin_is_constant_evaluated.
* testsuite/23_containers/array/tuple_interface/get_neg.cc:
Adjust dg-error lines.
Most ref-count updates in the COW string are done via the functions in
<ext/atomicity.h>, which will use non-atomic ops when the program is
known to be single-threaded. The _M_is_leaked() and _M_is_shared()
functions use __atomic_load_n directly, because <ext/atomicity.h>
doesn't provide a load operation. Those functions can check the
__is_single_threaded() predicate to avoid using __atomic_load_n when not
needed.
The move constructor for the fully-dynamic-string increments the
ref-count by either 2 or 1, for leaked or non-leaked strings
respectively. That can be changed to use a non-atomic store of 1 for all
non-shared strings. It can be non-atomic because even if the program is
multi-threaded, conflicting access to the rvalue object while it's being
moved from would be data race anyway. It can store 1 directly for all
non-shared strings because it doesn't matter whether the initial
refcount was -1 or 0, it should be 1 after the move constructor creates
a second owner.
libstdc++-v3/ChangeLog:
* include/bits/cow_string.h (basic_string::_M_is_leaked): Use
non-atomic load when __is_single_threaded() is true.
(basic_string::_M_is_shared): Likewise.
(basic_string::(basic_string&&)) [_GLIBCXX_FULLY_DYNAMIC_STRING]:
Use non-atomic store when rvalue is not shared.
When using COW strings, accessing _M_pathname[0] and similar non-const
accessors can cause the string to "leak", meaning it reallocates itself
if it shares ownership with another string object.
This causes test failures for --enable-fully-dynamic-string builds:
/home/jwakely/src/gcc/libstdc++-v3/testsuite/experimental/filesystem/path/construct/90634.cc:62: void test01(): Assertion 'bytes_allocated == 0' failed.
FAIL: experimental/filesystem/path/construct/90634.cc execution test
This FAIL happens because the fully-dynamic move constructor results in
shared ownership, so for path(std::move(std::string("foo"))) the
_M_pathname member shares ownership with the temporary, and the
non-const accesses in _M_split_cmpts() cause a new copy of the string to
be allocated. This un-sharing is wasteful, and entirely unnecessary when
sharing ownership with an rvalue that is about to release its ownership
anyway. Even for lvalues, sharing ownership is not a problem and
reallocating a unique copy of the string is wasteful.
This removes non-const accesses of _M_pathname in the
path::_M_split_cmpts() members.
libstdc++-v3/ChangeLog:
* src/c++17/fs_path.cc (path::_M_split_cmpts()): Remove
micro-optimization for "/" path.
* src/filesystem/path.cc (path::_M_split_cmpts()): Only access
the contents of _M_pathname using const member functions.
Fix some tests that assume that a moved-from string is empty, or that
default constructing a string doesn't allocate.
libstdc++-v3/ChangeLog:
* testsuite/21_strings/basic_string/cons/char/moveable.cc: Allow
moved-from string to be non-empty.
* testsuite/21_strings/basic_string/cons/char/moveable2.cc:
Likewise.
* testsuite/21_strings/basic_string/cons/char/moveable2_c++17.cc:
Likewise.
* testsuite/21_strings/basic_string/cons/wchar_t/moveable.cc:
Likewise.
* testsuite/21_strings/basic_string/cons/wchar_t/moveable2.cc:
Likewise.
* testsuite/21_strings/basic_string/cons/wchar_t/moveable2_c++17.cc:
Likewise.
* testsuite/21_strings/basic_string/modifiers/assign/char/87749.cc:
Construct empty string before setting oom flag.
* testsuite/21_strings/basic_string/modifiers/assign/wchar_t/87749.cc:
Likewise.
My last change to the fully-dynamic-string actually broke it. This fixes
the move constructor so it builds, and simplifies it slightly so that
more code is common between the fully-dynamic enabled/disabled cases.
libstdc++-v3/ChangeLog:
* include/bits/cow_string.h (basic_string(basic_string&&)): Fix
mem-initializer for _GLIBCXX_FULLY_DYNAMIC_STRING==0 case.
* testsuite/21_strings/basic_string/cons/char/noexcept_move_construct.cc:
Remove outdated comment.
* testsuite/21_strings/basic_string/cons/wchar_t/noexcept_move_construct.cc:
Likewise.
The definitions of the new C++20 members of std::stringstream etc are
missing when --with-default-libstdcxx-abi=gcc4-compatible is used,
because all the explicit instantiations in src/c++20/sstream-inst.cc are
skipped.
This ensures the contents of that file are compiled with the new ABI, so
the same set of symbols are exported regardless of which ABI is active
by default.
libstdc++-v3/ChangeLog:
* src/c++20/sstream-inst.cc (_GLIBCXX_USE_CXX11_ABI): Define to
select new ABI.
In C++17 mode all callers of _S_relocate have already done:
if constexpr (_S_use_relocate())
so we don't need to repeat that check and use tag dispatching to avoid
ill-formed instantiations.
libstdc++-v3/ChangeLog:
* include/bits/stl_vector.h (vector::_S_do_relocate): Remove
C++20 constexpr specifier.
(vector::_S_relocate) [__cpp_if_constexpr]: Call __relocate_a
directly without tag dispatching.
Clang doesn't define __SANITIZE_ADDRESS__ so use its __has_feature check
to detect Asan instead.
libstdc++-v3/ChangeLog:
PR libstdc++/103453
* config/allocator/malloc_allocator_base.h
(_GLIBCXX_SANITIZE_STD_ALLOCATOR): Define for Clang.
* config/allocator/new_allocator_base.h
(_GLIBCXX_SANITIZE_STD_ALLOCATOR): Likewise.
This patch adds [[nodiscard]] to std::byteswap, because the function
template doesn't do anything useful if the result isn't used.
2021-11-30 Jakub Jelinek <jakub@redhat.com>
* include/std/bit (byteswap): Add [[nodiscard]].
This patch attempts to implement P1272R4 (except for the std::bit_cast
changes in there which seem quite unrelated to this and will need to be
fixed on the compiler side).
While at least for GCC __builtin_bswap{16,32,64,128} should work fine
in constant expressions, I wonder about other compilers, so I'm using
a fallback implementation for constexpr evaluation always.
If you think that is unnecessary, I can drop the
__cpp_if_consteval >= 202106L &&
if !consteval
{
and
}
and reformat.
The fallback implementation is an attempt to make it work even for integral
types that don't have number of bytes divisible by 2 or when __CHAR_BIT__
is e.g. 16.
2021-11-28 Jakub Jelinek <jakub@redhat.com>
* include/std/bit (__cpp_lib_byteswap, byteswap): Define.
* include/std/version (__cpp_lib_byteswap): Define.
* testsuite/26_numerics/bit/bit.byteswap/byteswap.cc: New test.
* testsuite/26_numerics/bit/bit.byteswap/version.cc: New test.
This test was written to verify that the LWG 3265 changes work. But
those changes were superseded by LWG 3435, and the test is now incorrect
according to the current draft. The assignment operator is now
constrained to also require convertibility, which makes the test fail.
Change the Iter type to be convertible from int*, but make it throw an
exception if that conversion is used. Change the test from compile-only
to run, so we verify that the exception isn't thrown.
libstdc++-v3/ChangeLog:
* testsuite/24_iterators/move_iterator/dr3265.cc: Fix test to
account for LWG 3435 resolution.
When implementing constexpr std::vector I added a check for constant
evaluation in vector::_S_use_relocate(), so that we would not try to relocate
trivial objects by using memmove. But I put it in the constexpr function
that decides whether to relocate or not, and calls to that function are
always constant evaluated. This had the effect of disabling relocation
entirely, even in non-constexpr vectors.
This removes the check in _S_use_relocate() and modifies the actual
relocation algorithm, __relocate_a_1, to use the non-trivial
implementation instead of memmove when called during constant
evaluation.
libstdc++-v3/ChangeLog:
* include/bits/stl_uninitialized.h (__relocate_a_1): Do not use
memmove during constant evaluation.
* include/bits/stl_vector.h (vector::_S_use_relocate()): Do not
check is_constant_evaluated in always-constexpr function.
The FE bug was fixed, so we don't need this workaround now.
libstdc++-v3/ChangeLog:
PR libstdc++/96592
* include/std/tuple (tuple::is_constructible): Remove.
An 'xfail' selector means the test is expected to fail at runtime, so is
ignored for a compile-only test. The way to mark a compile-only test as
failing is with dg-error (which these already do).
libstdc++-v3/ChangeLog:
* testsuite/21_strings/basic_string_view/element_access/char/back_constexpr_neg.cc:
Remove xfail selector.
* testsuite/21_strings/basic_string_view/element_access/char/constexpr_neg.cc:
Likewise.
Likewise.
* testsuite/21_strings/basic_string_view/element_access/char/front_constexpr_neg.cc:
Likewise.
* testsuite/21_strings/basic_string_view/element_access/wchar_t/back_constexpr_neg.cc:
Likewise.
* testsuite/21_strings/basic_string_view/element_access/wchar_t/constexpr_neg.cc:
Likewise.
* testsuite/21_strings/basic_string_view/element_access/wchar_t/front_constexpr_neg.cc:
Likewise.
* testsuite/23_containers/span/101411.cc: Likewise.
* testsuite/25_algorithms/copy/debug/constexpr_neg.cc: Likewise.
* testsuite/25_algorithms/copy_backward/debug/constexpr_neg.cc:
Likewise.
* testsuite/25_algorithms/equal/constexpr_neg.cc: Likewise.
* testsuite/25_algorithms/equal/debug/constexpr_neg.cc: Likewise.
* testsuite/25_algorithms/lower_bound/debug/constexpr_partitioned_neg.cc:
Likewise.
* testsuite/25_algorithms/lower_bound/debug/constexpr_partitioned_pred_neg.cc:
Likewise.
* testsuite/25_algorithms/lower_bound/debug/constexpr_valid_range_neg.cc:
Likewise.
* testsuite/25_algorithms/upper_bound/debug/constexpr_partitioned_neg.cc:
Likewise.
* testsuite/25_algorithms/upper_bound/debug/constexpr_partitioned_pred_neg.cc:
Likewise.
* testsuite/25_algorithms/upper_bound/debug/constexpr_valid_range_neg.cc:
Likewise.
Some of the checks in 20_util/pointer_traits/lwg3545.cc really belong in
20_util/to_address/lwg3545 instead.
This also fixes the ordering of the dg-options and dg-do directives.
libstdc++-v3/ChangeLog:
* testsuite/20_util/pointer_traits/lwg3545.cc: Move to_address
tests to ...
* testsuite/20_util/to_address/lwg3545.cc: ... here. Add -std
option before checking effective target.
There was a c++11_only dg-error in this testcase, for a "body of
constexpr function is not a return statement" diagnostic that was bogus,
but happened because the return statement was ill-formed. A change to
G++ earlier this month means that diagnostic is no longer emitted, so
remove the dg-error.
libstdc++-v3/ChangeLog:
* testsuite/20_util/tuple/comparison_operators/overloaded2.cc:
Remove dg-error for C++11_only error.
This implements the resolution I'm proposing for LWG 3545, to avoid hard
errors when using std::to_address for types that make pointer_traits
ill-formed.
Consistent with std::iterator_traits, instantiating std::pointer_traits
for a non-pointer type will be well-formed, but give an empty type with
no member types. This avoids the problematic cases for std::to_address.
Additionally, the pointer_to member is now only declared when the
element type is not cv void (and for C++20, when the function body would
be well-formed). The rebind member was already SFINAE-friendly in our
implementation.
libstdc++-v3/ChangeLog:
PR libstdc++/96416
* include/bits/ptr_traits.h (pointer_traits): Reimplement to be
SFINAE-friendly (LWG 3545).
* testsuite/20_util/pointer_traits/lwg3545.cc: New test.
* testsuite/20_util/to_address/1_neg.cc: Adjust dg-error line.
* testsuite/20_util/to_address/lwg3545.cc: New test.
libstdc++-v3/ChangeLog:
PR libstdc++/101608
* include/bits/ranges_algobase.h (__fill_n_fn): Check for
constant evaluation before using memset.
* testsuite/25_algorithms/fill_n/constrained.cc: Check
byte-sized values as well.
The type printers are not substituting std::string for
std::basic_string<char> in debug mode, mark some tests as xfail.
libstdc++-v3/ChangeLog:
* testsuite/libstdc++-prettyprinters/80276.cc: Add xfail for
debug mode.
* testsuite/libstdc++-prettyprinters/libfundts.cc: Likewise.
An effective target like foo-bar-baz will match a target selector of
*-*-* and cause problems in the testsuite. Several libstdc++ et keywords
are of the form foo-bar, which could still be a problem for *-*
selectors.
Replace hyphens with underscores in the et keywords "debug-mode",
"cxx11-abi", etc.
libstdc++-v3/ChangeLog:
* testsuite/lib/libstdc++.exp: Rename effective target keywords
to avoid dashes in the name.
* testsuite/*: Update effective targe keywords.
This allows tests to be skipped if the std::allocator implementation is
not __gnu_cxx::new_allocator.
The 20_util/allocator/overaligned.cc test requires either C++17 or
new_allocator, otherwise we can't guarantee to return overaligned
memory.
libstdc++-v3/ChangeLog:
* testsuite/18_support/50594.cc: Check effective target.
* testsuite/20_util/allocator/1.cc: Likewise.
* testsuite/20_util/allocator/overaligned.cc: Likewise.
* testsuite/23_containers/unordered_map/96088.cc: Likewise.
* testsuite/23_containers/unordered_multimap/96088.cc: Likewise.
* testsuite/23_containers/unordered_multiset/96088.cc: Likewise.
* testsuite/23_containers/unordered_set/96088.cc: Likewise.
* testsuite/ext/throw_allocator/check_delete.cc: Likewise.
* testsuite/ext/throw_allocator/check_new.cc: Likewise.
* testsuite/lib/libstdc++.exp (check_effective_target_std_allocator_new):
Define new proc.
<ext/bitmap_allocator.h> includes <function>, and since C++17 that
includes <unordered_map>. If std::allocator is defined in terms of
__gnu_cxx::bitmap_allocator then you get a circular reference and
bootstrap fails when compiling src/c++17/*.cc.
libstdc++-v3/ChangeLog:
PR libstdc++/103381
* include/ext/bitmap_allocator.h: Include <bits/stl_function.h>
instead of <functional>.
The check for C++14 was using the wrong date.
libstdc++-v3/ChangeLog:
* include/bits/c++config (_GLIBCXX14_DEPRECATED): Fix condition
checking for C++14.
This replaces a __gthread_active_p() check with __is_single_threaded()
so that std::locale initialization doesn't use __gthread_once if it
happens before the first thread is created.
This means that _S_initialize_once() might now be called twice instead
of only once, because if __is_single_threaded() changes to false then we
will do the __gthread_once call even if _S_initialize_once() was already
called. Add a check to _S_initialize_once() and return immediately if
it is the second call.
Also use __builtin_expect to _S_initialize, as the branch will be taken
at most once in the lifetime of the program.
libstdc++-v3/ChangeLog:
* src/c++98/locale_init.cc (_S_initialize_once): Check if
initialization has already been done.
(_S_initialize): Replace __gthread_active_p with
__is_single_threaded. Use __builtin_expect.
All writes into the allocated buffer need to be via traits_type::assign
to begin lifetimes.
libstdc++-v3/ChangeLog:
PR libstdc++/103295
* include/bits/basic_string.tcc (_M_construct): Use the
traits assign member to write into allcoated memory.
Depending on the permutation of CPU, OS version and shared/non-
shared library inclusion, we get can get warnings from the external
tools (ld64, dsymutil) which are not actually libstdc++ issues but
relate to the external tools themselves. This is already pruned
in the main testsuite, this adds it to the library.
Signed-off-by: Iain Sandoe <iain@sandoe.co.uk>
libstdc++-v3/ChangeLog:
* testsuite/lib/prune.exp: Prune dsymutil (ld64) warning.
Clang gives errors for constexpr std::string because the memory returned
by std::allocator<T>::allocate does not contain any objects yet, and
attempting to set them using char_traits::assign or char_traits::copy
fails with:
assignment to object outside its lifetime is not allowed in a constant expression
*__result = *__first;
^
This adds code to std::char_traits to use std::construct_at to begin
lifetimes when called during constant evaluation. To support
specializations of std::basic_string that don't use std::char_traits
there is now another layer of wrapper around the allocator_traits, so
that the lifetime of characters is begun as soon as the memory is
allocated. By doing it in the char traits and allocator traits, the rest
of basic_string can ignore the problem.
While modifying char_traits::copy and char_traits::assign to begin
lifetimes for the constexpr cases, I also replaced their uses of
std::copy and std::fill_n respectively. That means we don't need
<bits/stl_algobase.h> for char_traits.
libstdc++-v3/ChangeLog:
PR libstdc++/103295
* include/bits/basic_string.h (_Alloc_traits): Replace typedef
with struct for C++20 mode.
* include/bits/basic_string.tcc (_M_replace): Use _Alloc_traits
for allocation.
* include/bits/char_traits.h (__gnu_cxx::char_traits::assign):
Use std::_Construct during constant evaluation.
(__gnu_cxx::char_traits::assign(CharT*, const CharT*, size_t)):
Likewise. Replace std::fill_n with memset or manual loop.
(__gnu_cxx::char_traits::copy): Likewise, replacing std::copy
with memcpy.
* include/ext/vstring.h: Include <bits/stl_algobase.h> for
std::min.
* include/std/string_view: Likewise.
* testsuite/21_strings/basic_string/capacity/char/resize_and_overwrite.cc:
Add constexpr test.
Newlib changed ctype.h recently[1] by moving the short labels from ctype.h intro
the private namespace in ctype_.h. This broke embedded builds due to them no
longer being found. Instead they now expose the long names to match glibc.
This patch now uses the short or long names depending on is the short ones are
defined or not.
[1] 3ba1bd0d9d
libstdc++-v3/ChangeLog:
PR libstdc++/103305
* config/os/newlib/ctype_base.h (upper, lower, alpha, digit, xdigit,
space, print, graph, cntrl, punct, alnum, blank): Use short or long
names depending on if short ones are defined.
The constexpr branch in __gnu_cxx::char_traits::move compares the string
arguments to see if they overlap, but relational comparisons between
unrelated pointers are not core constant expressions.
I want to replace the comparisons with a loop using pointer equality to
determine whether the end of the source string is in the destination
string. However, that doesn't work with GCC, due to PR c++/89074 so
allocate a temporary buffer instead and copy out into that first, so
that overlapping source and destination don't matter. The allocation
isn't supported by the current Intel icc so use the loop as a fallback.
libstdc++-v3/ChangeLog:
* include/bits/char_traits.h (__gnu_cxx::char_traits::move):
Do not compare unrelated pointers during constant evaluation.
* testsuite/21_strings/char_traits/requirements/constexpr_functions_c++20.cc:
Improve tests for char_traits::move.
This replaces most uses of AC_CACHE_VAL with AC_CACHE_CHECK, which means
we don't need separate AC_MSG_CHECKING and AC_MSG_RESULT macros.
There are a few trivial bugs fixed as a side effect, where an
AC_MSG_RESULT was printed out even if the actual checks hadn't been
done. That didn't affect the results, only the content of config.log.
libstdc++-v3/ChangeLog:
* acinclude.m4: Replace AC_CACHE_VAL with AC_CACHE_CHECK.
* configure: Regenerate.
The constexpr std::string commit was my own work, but the commit still
had the author name from an earlier cherry-pick that eventually got
entirely reverted. This fixes the name in the ChangeLog file.
Using placement-new isn't valid in constant expressions, so this
replaces it with std::construct_at (via the std::_Construct function
that is usable before C++20).
libstdc++-v3/ChangeLog:
* include/experimental/internet (address): Use std::_Construct
to initialize union members.
Several std::basic_string constructors dispatch to one of the
two-argument overloads of _M_construct, which then dispatches again to
_M_construct_aux to detect whether the arguments are iterators or not.
That then dispatches to one of _M_construct(size_type, char_type) or
_M_construct(Iter, Iter, iterator_traits<Iter>::iterator_category{}).
For most of those constructors this is a waste of time, because we know
the arguments are already iterators. For basic_string(const CharT*) and
basic_string(initializer_list<C>) we know that we call _M_construct with
two pointers, and for basic_string(const basic_string&) we call it with
two const_iterators. Those constructors can call the three-argument
overload of _M_construct with the iterator category tag right away,
without the intermediate dispatching.
The case where this doesn't apply is basic_string(InputIter, InputIter),
but for C++11 and later this is constrained so we know it's an iterator
here as well. We can restrict the dispatching in this constructor to
only be done for C++98 and to call _M_construct_aux directly, which
allows us to remove the two-argument _M_construct(InputIter, InputIter)
overload entirely.
N.B. When calling the three-arg _M_construct with pointers or string
iterators, we pass forward_iterator_tag not random_access_iterator_tag.
This is because it makes no difference which overload gets called, and
simplifies overload resolution to not have to do a base-to-derived
check. If we ever add a new overload of M_construct for random access
iterators we would have to revisit this, but that seems unlikely.
This patch also moves the __is_null_pointer checks from the three-arg
_M_construct into the constructors where a null pointer argument is
actually possible. This avoids redundant checks where we know we have a
non-null pointer, or don't have a pointer at all.
Finally, this patch replaces some try-blocks with an RAII type, so that
memory is deallocated during unwinding. This avoids the overhead of
catching and rethrowing an exception.
libstdc++-v3/ChangeLog:
* include/bits/basic_string.h (_M_construct_aux): Only define
for C++98. Remove constexpr.
(_M_construct_aux_2): Likewise.
(_M_construct(InputIter, InputIter)): Remove.
(basic_string(const basic_string&)): Call _M_construct with
iterator category argument.
(basic_string(const basic_string&, size_type, const Alloc&)):
Likewise.
(basic_string(const basic_string&, size_type, size_type)):
Likewise.
(basic_string(const charT*, size_type, const Alloc&)): Likewise.
Check for null pointer.
(basic_string(const charT*, const Alloc&)): Likewise.
(basic_string(initializer_list<charT>, const Alloc&)): Call
_M_construct with iterator category argument.
(basic_string(const basic_string&, const Alloc&)): Likewise.
(basic_string(basic_string&&, const Alloc&)): Likewise.
(basic_string(_InputIter, _InputIter, const Alloc&)): Likewise
for C++11 and later, call _M_construct_aux for C++98.
* include/bits/basic_string.tcc
(_M_construct(I, I, input_iterator_tag)): Replace try-block with
RAII type.
(_M_construct(I, I, forward_iterator_tag)): Likewise. Remove
__is_null_pointer check.
Clang diagnoses that the new constexpr std::string constructors are not
usable in constant expressions, because they start to write to members
of the union without setting an active member.
This adds a new helper function which returns the address of the local
buffer after making it the active member.
This doesn't fix all problems with Clang, because it still refuses to
write to memory returned by the allocator.
libstdc++-v3/ChangeLog:
PR libstdc++/103295
* include/bits/basic_string.h (_M_use_local_data()): New
member function to make local buffer the active member.
(assign(const basic_string&)): Use it.
* include/bits/basic_string.tcc (_M_construct, reserve()):
Likewise.
The r179236 fix for std::type_info::operator== should also have been
applied to std::type_info::before. Otherwise two distinct types can
compare equivalent due to using a string comparison, when they should do
a pointer comparison.
libstdc++-v3/ChangeLog:
PR libstdc++/103240
* libsupc++/tinfo2.cc (type_info::before): Use unadjusted name
to check for the '*' prefix.
* testsuite/util/testsuite_shared.cc: Add type_info object for
use in new test.
* testsuite/18_support/type_info/103240.cc: New test.
Some tests fail when run with -D_GLIBCXX_USE_CXX11_ABI or -stdgnu++20.
libstdc++-v3/ChangeLog:
* include/bits/basic_string.h (operator<=>): Use constexpr
unconditionally.
* testsuite/21_strings/basic_string/modifiers/constexpr.cc:
Require cxx11-abit effective target.
* testsuite/21_strings/headers/string/synopsis.cc: Add
conditional constexpr to declarations, and adjust relational
operators for C++20.
This is only supported for the cxx11 ABI, not for COW strings.
libstdc++-v3/ChangeLog:
* include/bits/basic_string.h (basic_string, operator""s): Add
constexpr for C++20.
(basic_string::basic_string(basic_string&&)): Only copy
initialized portion of the buffer.
(basic_string::basic_string(basic_string&&, const Alloc&)):
Likewise.
* include/bits/basic_string.tcc (basic_string): Add constexpr
for C++20.
(basic_string::swap(basic_string&)): Only copy initialized
portions of the buffers.
(basic_string::_M_replace): Add constexpr implementation that
doesn't depend on pointer comparisons.
* include/bits/cow_string.h: Adjust comment.
* include/ext/type_traits.h (__is_null_pointer): Add constexpr.
* include/std/string (erase, erase_if): Add constexpr.
* include/std/version (__cpp_lib_constexpr_string): Update
value.
* testsuite/21_strings/basic_string/cons/char/constexpr.cc:
New test.
* testsuite/21_strings/basic_string/cons/wchar_t/constexpr.cc:
New test.
* testsuite/21_strings/basic_string/literals/constexpr.cc:
New test.
* testsuite/21_strings/basic_string/modifiers/constexpr.cc: New test.
* testsuite/21_strings/basic_string/modifiers/swap/char/constexpr.cc:
New test.
* testsuite/21_strings/basic_string/modifiers/swap/wchar_t/constexpr.cc:
New test.
* testsuite/21_strings/basic_string/version.cc: New test.
These swap overloads are non-standard, but are needed to make swap work
for vector<bool>::reference rvalues. They don't need to be called
explicitly, only via ADL, so hide them from normal lookup. This is what
I've proposed as the resolution to LWG 3638.
libstdc++-v3/ChangeLog:
* include/bits/stl_bvector.h (swap(_Bit_reference, _Bit_reference))
(swap(_Bit_reference, bool&), swap(bool&, _Bit_reference)):
Define as hidden friends of _Bit_reference.
I fixed some undefined behaviour in string tests in r238609, but I only
fixed the narrow char versions. This applies the same fixes to the
wchar_t ones. These problems were found when testing a patch to make
std::basic_string usable in constexpr.
libstdc++-v3/ChangeLog:
* testsuite/21_strings/basic_string/modifiers/append/wchar_t/1.cc:
Fix reads past the end of strings.
* testsuite/21_strings/basic_string/operations/compare/wchar_t/1.cc:
Likewise.
* testsuite/experimental/string_view/operations/compare/wchar_t/1.cc:
Likewise.
With each successive C++ standard the restrictions on the use of the
constexpr keyword for functions get weaker and weaker; it recently occurred
to me that it is heading toward the same fate as the C register keyword,
which was once useful for optimization but became obsolete. Similarly, it
seems to me that we should be able to just treat inlines as constexpr
functions and not make people add the extra keyword everywhere.
There were a lot of testcase changes needed; many disabling errors about
non-constexpr functions that are now constexpr, and many disabling implicit
constexpr so that the tests can check the same thing as before, whether
that's mangling or whatever.
gcc/c-family/ChangeLog:
* c.opt: Add -fimplicit-constexpr.
* c-cppbuiltin.c: Define __cpp_implicit_constexpr.
* c-opts.c (c_common_post_options): Disable below C++14.
gcc/cp/ChangeLog:
* cp-tree.h (struct lang_decl_fn): Add implicit_constexpr.
(decl_implicit_constexpr_p): New.
* class.c (type_maybe_constexpr_destructor): Use
TYPE_HAS_TRIVIAL_DESTRUCTOR and maybe_constexpr_fn.
(finalize_literal_type_property): Simplify.
* constexpr.c (is_valid_constexpr_fn): Check for dtor.
(maybe_save_constexpr_fundef): Try to set DECL_DECLARED_CONSTEXPR_P
on inlines.
(cxx_eval_call_expression): Use maybe_constexpr_fn.
(maybe_constexpr_fn): Handle flag_implicit_constexpr.
(var_in_maybe_constexpr_fn): Use maybe_constexpr_fn.
(potential_constant_expression_1): Likewise.
(decl_implicit_constexpr_p): New.
* decl.c (validate_constexpr_redeclaration): Allow change with
-fimplicit-constexpr.
(grok_special_member_properties): Use maybe_constexpr_fn.
* error.c (dump_function_decl): Don't print 'constexpr'
if it's implicit.
* Make-lang.in (check-c++-all): Update.
libstdc++-v3/ChangeLog:
* testsuite/20_util/to_address/1_neg.cc: Adjust error.
* testsuite/26_numerics/random/concept.cc: Adjust asserts.
gcc/testsuite/ChangeLog:
* lib/g++-dg.exp: Handle "impcx".
* lib/target-supports.exp
(check_effective_target_implicit_constexpr): New.
* g++.dg/abi/abi-tag16.C:
* g++.dg/abi/abi-tag18a.C:
* g++.dg/abi/guard4.C:
* g++.dg/abi/lambda-defarg1.C:
* g++.dg/abi/mangle26.C:
* g++.dg/cpp0x/constexpr-diag3.C:
* g++.dg/cpp0x/constexpr-ex1.C:
* g++.dg/cpp0x/constexpr-ice5.C:
* g++.dg/cpp0x/constexpr-incomplete2.C:
* g++.dg/cpp0x/constexpr-memfn1.C:
* g++.dg/cpp0x/constexpr-neg3.C:
* g++.dg/cpp0x/constexpr-specialization.C:
* g++.dg/cpp0x/inh-ctor19.C:
* g++.dg/cpp0x/inh-ctor30.C:
* g++.dg/cpp0x/lambda/lambda-mangle3.C:
* g++.dg/cpp0x/lambda/lambda-mangle5.C:
* g++.dg/cpp1y/auto-fn12.C:
* g++.dg/cpp1y/constexpr-loop5.C:
* g++.dg/cpp1z/constexpr-lambda7.C:
* g++.dg/cpp2a/constexpr-dtor3.C:
* g++.dg/cpp2a/constexpr-new13.C:
* g++.dg/cpp2a/constinit11.C:
* g++.dg/cpp2a/constinit12.C:
* g++.dg/cpp2a/constinit14.C:
* g++.dg/cpp2a/constinit15.C:
* g++.dg/cpp2a/spaceship-constexpr1.C:
* g++.dg/cpp2a/spaceship-eq3.C:
* g++.dg/cpp2a/udlit-class-nttp-neg2.C:
* g++.dg/debug/dwarf2/auto1.C:
* g++.dg/debug/dwarf2/cdtor-1.C:
* g++.dg/debug/dwarf2/lambda1.C:
* g++.dg/debug/dwarf2/pr54508.C:
* g++.dg/debug/dwarf2/pubnames-2.C:
* g++.dg/debug/dwarf2/pubnames-3.C:
* g++.dg/ext/is_literal_type3.C:
* g++.dg/ext/visibility/template7.C:
* g++.dg/gcov/gcov-12.C:
* g++.dg/gcov/gcov-2.C:
* g++.dg/ipa/devirt-35.C:
* g++.dg/ipa/devirt-36.C:
* g++.dg/ipa/devirt-37.C:
* g++.dg/ipa/devirt-44.C:
* g++.dg/ipa/imm-devirt-1.C:
* g++.dg/lookup/builtin5.C:
* g++.dg/lto/inline-crossmodule-1_0.C:
* g++.dg/modules/enum-1_a.C:
* g++.dg/modules/fn-inline-1_c.C:
* g++.dg/modules/pmf-1_b.C:
* g++.dg/modules/used-1_c.C:
* g++.dg/tls/thread_local11.C:
* g++.dg/tls/thread_local11a.C:
* g++.dg/tm/pr46653.C:
* g++.dg/ubsan/pr70035.C:
* g++.old-deja/g++.other/delete6.C:
* g++.dg/modules/pmf-1_a.H:
Adjust for implicit constexpr.
When merging 2 unordered containers with same hasher we can re-use the hash code from
the cache if any.
Also in the context of the merge operation on multi-container use previous insert iterator as a hint
for the next insert.
libstdc++-v3/ChangeLog:
* include/bits/hashtable_policy.h:
(_Hash_code_base<>::_M_hash_code(const _Hash&, const _Hash_node_value<_Value, true>&)): New.
(_Hash_code_base<>::_M_hash_code<_H2>(const _H2&, const _Hash_node_value<>&)): New.
* include/bits/hashtable.h (_Hashtable<>::_M_merge_unique): Use latter.
(_Hashtable<>::_M_merge_multi): Likewise.
* testsuite/23_containers/unordered_multiset/modifiers/merge.cc (test05): New test.
* testsuite/23_containers/unordered_set/modifiers/merge.cc (test04): New test.
The implicit constexpr patch revealed that our checks for constexpr
constructors that could possibly produce a constant value (which
otherwise are IFNDR) was failing to look at most of the function body.
Fixing that required some library tweaks.
gcc/cp/ChangeLog:
* constexpr.c (maybe_save_constexpr_fundef): Also check whether the
body of a constructor is potentially constant.
libstdc++-v3/ChangeLog:
* src/c++17/memory_resource.cc: Add missing constexpr.
* include/experimental/internet: Only mark copy constructor
as constexpr with __cpp_constexpr_dynamic_alloc.
gcc/testsuite/ChangeLog:
* g++.dg/cpp1y/constexpr-89285-2.C: Expect error.
* g++.dg/cpp1y/constexpr-89285.C: Adjust error.
Since r12-5056-g3439657b0286, there has been a regression in
test results; an additional 100 FAILs running the g++ and
libstdc++ testsuite on cris-elf, a newlib target. The
failures are linker errors, not finding a definition for
getentropy. It appears newlib has since 2017-12-03
declarations of getentropy and arc4random, and provides an
implementation of arc4random using getentropy, but provides no
definition of getentropy, not even a stub yielding ENOSYS.
This is similar to what it does for many other functions too.
While fixing newlib (like adding said stub) would likely help,
it still leaves older newlib releases hanging. Thankfully,
the libstdc++ configury test can be improved to try linking
where possible; using the bespoke GCC_TRY_COMPILE_OR_LINK
instead of AC_TRY_COMPILE. BTW, I see a lack of consistency;
some tests use AC_TRY_COMPILE and some GCC_TRY_COMPILE_OR_LINK
for no apparent reason, but this commit just amends
r12-5056-g3439657b0286.
libstdc++-v3:
PR libstdc++/103166
* acinclude.m4 (GLIBCXX_CHECK_GETENTROPY, GLIBCXX_CHECK_ARC4RANDOM):
Use GCC_TRY_COMPILE_OR_LINK instead of AC_TRY_COMPILE.
* configure: Regenerate.
This replaces the printf used by failed debug assertions with fprintf,
so we can write to stderr.
To avoid including <stdio.h> the assert function is moved into the
library. To avoid programs using a vague linkage definition of the old
inline function, the function is renamed. Code compiled with old
versions of GCC might still call the old function, but code compiled
with the newer GCC will call the new function and write to stderr.
libstdc++-v3/ChangeLog:
PR libstdc++/59675
* acinclude.m4 (libtool_VERSION): Bump version.
* config/abi/pre/gnu.ver (GLIBCXX_3.4.30): Add version and
export new symbol.
* configure: Regenerate.
* include/bits/c++config (__replacement_assert): Remove, declare
__glibcxx_assert_fail instead.
* src/c++11/debug.cc (__glibcxx_assert_fail): New function to
replace __replacement_assert, writing to stderr instead of
stdout.
* testsuite/util/testsuite_abi.cc: Update latest version.
This implements P1004R2 ("Making std::vector constexpr") for C++20.
For now, debug mode vectors are not supported in constant expressions.
To make that work we might need to disable all attaching/detaching of
safe iterators. That can be fixed later.
Co-authored-by: Josh Marshall <joshua.r.marshall.1991@gmail.com>
libstdc++-v3/ChangeLog:
* include/bits/alloc_traits.h (_Destroy): Make constexpr for
C++20 mode.
* include/bits/allocator.h (__shrink_to_fit::_S_do_it):
Likewise.
* include/bits/stl_algobase.h (__fill_a1): Declare _Bit_iterator
overload constexpr for C++20.
* include/bits/stl_bvector.h (_Bit_type, _S_word_bit): Move out
of inline namespace.
(_Bit_reference, _Bit_iterator_base, _Bit_iterator)
(_Bit_const_iterator, _Bvector_impl_data, _Bvector_base)
(vector<bool, A>>): Add constexpr to every member function.
(_Bvector_base::_M_allocate): Initialize storage during constant
evaluation.
(vector<bool, A>::_M_initialize_value): Use __fill_bvector_n
instead of memset.
(__fill_bvector_n): New helper function to replace memset during
constant evaluation.
* include/bits/stl_uninitialized.h (__uninitialized_copy<false>):
Move logic to ...
(__do_uninit_copy): New function.
(__uninitialized_fill<false>): Move logic to ...
(__do_uninit_fill): New function.
(__uninitialized_fill_n<false>): Move logic to ...
(__do_uninit_fill_n): New function.
(__uninitialized_copy_a): Add constexpr. Use __do_uninit_copy.
(__uninitialized_move_a, __uninitialized_move_if_noexcept_a):
Add constexpr.
(__uninitialized_fill_a): Add constexpr. Use __do_uninit_fill.
(__uninitialized_fill_n_a): Add constexpr. Use
__do_uninit_fill_n.
(__uninitialized_default_n, __uninitialized_default_n_a)
(__relocate_a_1, __relocate_a): Add constexpr.
* include/bits/stl_vector.h (_Vector_impl_data, _Vector_impl)
(_Vector_base, vector): Add constexpr to every member function.
(_Vector_impl::_S_adjust): Disable ASan annotation during
constant evaluation.
(_Vector_base::_S_use_relocate): Disable bitwise-relocation
during constant evaluation.
(vector::_Temporary_value): Use a union for storage.
* include/bits/vector.tcc (vector, vector<bool>): Add constexpr
to every member function.
* include/std/vector (erase_if, erase): Add constexpr.
* testsuite/23_containers/headers/vector/synopsis.cc: Add
constexpr for C++20 mode.
* testsuite/23_containers/vector/bool/cmp_c++20.cc: Change to
compile-only test using constant expressions.
* testsuite/23_containers/vector/bool/capacity/29134.cc: Adjust
namespace for _S_word_bit.
* testsuite/23_containers/vector/bool/modifiers/insert/31370.cc:
Likewise.
* testsuite/23_containers/vector/cmp_c++20.cc: Likewise.
* testsuite/23_containers/vector/cons/89164.cc: Adjust errors
for C++20 and move C++17 test to ...
* testsuite/23_containers/vector/cons/89164_c++17.cc: ... here.
* testsuite/23_containers/vector/bool/capacity/constexpr.cc: New test.
* testsuite/23_containers/vector/bool/cons/constexpr.cc: New test.
* testsuite/23_containers/vector/bool/element_access/constexpr.cc: New test.
* testsuite/23_containers/vector/bool/modifiers/assign/constexpr.cc: New test.
* testsuite/23_containers/vector/bool/modifiers/constexpr.cc: New test.
* testsuite/23_containers/vector/bool/modifiers/swap/constexpr.cc: New test.
* testsuite/23_containers/vector/capacity/constexpr.cc: New test.
* testsuite/23_containers/vector/cons/constexpr.cc: New test.
* testsuite/23_containers/vector/data_access/constexpr.cc: New test.
* testsuite/23_containers/vector/element_access/constexpr.cc: New test.
* testsuite/23_containers/vector/modifiers/assign/constexpr.cc: New test.
* testsuite/23_containers/vector/modifiers/constexpr.cc: New test.
* testsuite/23_containers/vector/modifiers/swap/constexpr.cc: New test.
Since r12-5072 made _Safe_container::operator=(const _Safe_container&)
protected, the debug containers no longer compile in C++98 mode. They
have user-provided copy assignment operators in C++98 mode, and they
assign each base class in turn. The 'this->_M_safe() = __x' expressions
fail, because calling a protected member function is only allowed via
'this'. They could be fixed by using this->_Safe::operator=(__x) but a
simpler solution is to just remove the user-provided assignment
operators and let the compiler define them (as we do for C++11 and
later, by defining them as defaulted).
The only change needed for that to work is to define the _Safe_vector
copy assignment operator in C++98 mode, so that the implicit
__gnu_debug::vector::operator= definition will call it, instead of
needing to call _M_update_guaranteed_capacity() manually.
libstdc++-v3/ChangeLog:
* include/debug/deque (deque::operator=(const deque&)): Remove
definition.
* include/debug/list (list::operator=(const list&)): Likewise.
* include/debug/map.h (map::operator=(const map&)): Likewise.
* include/debug/multimap.h (multimap::operator=(const multimap&)):
Likewise.
* include/debug/multiset.h (multiset::operator=(const multiset&)):
Likewise.
* include/debug/set.h (set::operator=(const set&)): Likewise.
* include/debug/string (basic_string::operator=(const basic_string&)):
Likewise.
* include/debug/vector (vector::operator=(const vector&)):
Likewise.
(_Safe_vector::operator=(const _Safe_vector&)): Define for
C++98 as well.
Calling the placement version of ::operator new "implicitly creates
objects in the returned region of storage" as per [intro.object]. This
allows the returned memory to be used as storage for implicit-lifetime
types (including arrays) without additional action by the caller. This
is required by the proposed resolution of LWG 3147.
libstdc++-v3/ChangeLog:
* include/std/memory_resource (memory_resource::allocate):
Implicitly create objects in the returned storage.
This function only exists to avoid an error in the debug mode vector, so
doesn't need to be public.
libstdc++-v3/ChangeLog:
* include/bits/stl_bvector.h (vector<bool>::data()): Give
protected access, and delete for C++11 and later.
The <cxxx> headers for the C library are not under our control, so we
can't prevent them from including <unistd.h>. Change the PR 49745 test
to only include the C++ library headers, not the <cxxx> ones.
To ensure <bits/stdc++.h> isn't included automatically we need to use
no_pch to disable PCH.
libstdc++-v3/ChangeLog:
PR libstdc++/100117
* testsuite/17_intro/headers/c++1998/49745.cc: Explicitly list
all C++ headers instead of including <bits/stdc++.h>
Since Glibc 2.34 all pthreads symbols are defined directly in libc not
libpthread, and since Glibc 2.32 we have used __libc_single_threaded to
avoid unnecessary locking in single-threaded programs. This means there
is no reason to avoid linking to libpthread now, and so no reason to use
weak symbols defined in gthr-posix.h for all the pthread_xxx functions.
libstdc++-v3/ChangeLog:
PR libstdc++/100748
PR libstdc++/103133
* config/os/gnu-linux/os_defines.h (_GLIBCXX_GTHREAD_USE_WEAK):
Define for glibc 2.34 and later.
We need to use the 64-bit DARN to detect failure without bias, but it's
not available in 32-bit mode.
libstdc++-v3/ChangeLog:
PR libstdc++/103146
* src/c++11/random.cc: Check __powerpc64__ not __powerpc__.
This adds additional "getentropy" and "arc4random" tokens to
std::random_device. The former is supported on Glibc and OpenBSD (and
apparently wasm), and the latter is supported on various BSDs.
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_CHECK_GETENTROPY, GLIBCXX_CHECK_ARC4RANDOM):
Define.
* configure.ac (GLIBCXX_CHECK_GETENTROPY, GLIBCXX_CHECK_ARC4RANDOM):
Use them.
* config.h.in: Regenerate.
* configure: Regenerate.
* src/c++11/random.cc (random_device): Add getentropy and
arc4random as sources.
* testsuite/26_numerics/random/random_device/cons/token.cc:
Check new tokens.
* testsuite/26_numerics/random/random_device/entropy.cc:
Likewise.
It's possible that independent reads from /dev/random and /dev/urandom
could produce the same value by chance. Retry if that happens. The
chances of it happening twice are miniscule.
libstdc++-v3/ChangeLog:
* testsuite/26_numerics/random/random_device/cons/token.cc:
Retry if random devices produce the same value.
According to
https://gcc.gnu.org/legacy-ml/gcc-patches/2008-03/msg01698.html, the
TLS support, including the __tls_lookup function, was added to VxWorks
in 6.6.
It certainly doesn't exist on our VxWorks 5 platform, but the fallback
code in eh_globals.cc using __gthread_key_create() etc. used to work
just fine.
libstdc++-v3/ChangeLog:
* config/os/vxworks/os_defines.h (_GLIBCXX_HAVE_TLS): Only
define for VxWorks >= 6.6.
