This fixes the remaining filesystem::remove_all race condition by using
POSIX openat to recurse into sub-directories and using POSIX unlinkat to
remove files. This avoids the remaining race where the directory being
removed is replaced with a symlink after the directory has been opened,
so that the filesystem::remove("subdir/file") resolves to "target/file"
instead, because "subdir" has been removed and replaced with a symlink.
The previous patch only fixed the case where the directory was replaced
with a symlink before we tried to open it, but it still used the full
(potentially compromised) path as an argument to filesystem::remove.
The first part of the fix is to use openat when recursing into a
sub-directory with recursive_directory_iterator. This means that opening
"dir/subdir" uses the file descriptor for "dir", and so is sure to open
"dir/subdir" and not "symlink/subdir". (The previous patch to use
O_NOFOLLOW already ensured we won't open "dir/symlink/" here.)
The second part of the fix is to use unlinkat for the remove_all
operation. Previously we used a directory_iterator to get the name of
each file in a directory and then used filesystem::remove(iter->path())
on that name. This meant that any checks (e.g. O_NOFOLLOW) done by the
iterator could be invalidated before the remove operation on that
pathname. The directory iterator contains an open DIR stream, which we
can use to obtain a file descriptor to pass to unlinkat. This ensures
that the file being deleted really is contained within the directory
we're iterating over, rather than using a pathname that could resolve to
some other file.
The filesystem::remove_all function previously used a (non-recursive)
filesystem::directory_iterator for each directory, and called itself
recursively for sub-directories. The new implementation uses a single
filesystem::recursive_directory_iterator object, and calls a new __erase
member function on that iterator. That new __erase member function does
the actual work of removing a file (or a directory after its contents
have been iterated over and removed) using unlinkat. That means we don't
need to expose the DIR stream or its file descriptor to the remove_all
function, it's still encapuslated by the iterator class.
It would be possible to add a __rewind member to directory iterators
too, to call rewinddir after each modification to the directory. That
would make it more likely for filesystem::remove_all to successfully
remove everything even if files are being written to the directory tree
while removing it. It's unclear if that is actually prefereable, or if
it's better to fail and report an error at the first opportunity.
The necessary APIs (openat, unlinkat, fdopendir, dirfd) are defined in
POSIX.1-2008, and in Glibc since 2.10. But if the target doesn't provide
them, the original code (with race conditions) is still used.
This also reduces the number of small memory allocations needed for
std::filesystem::remove_all, because we do not store the full path to
every directory entry that is iterated over. The new filename_only
option means we only store the filename in the directory entry, as that
is all we need in order to use openat or unlinkat.
Finally, rather than duplicating everything for the Filesystem TS, the
std::experimental::filesystem::remove_all implementation now just calls
std::filesystem::remove_all to do the work.
libstdc++-v3/ChangeLog:
PR libstdc++/104161
* acinclude.m4 (GLIBCXX_CHECK_FILESYSTEM_DEPS): Check for dirfd
and unlinkat.
* config.h.in: Regenerate.
* configure: Regenerate.
* include/bits/fs_dir.h (recursive_directory_iterator): Declare
remove_all overloads as friends.
(recursive_directory_iterator::__erase): Declare new member
function.
* include/bits/fs_fwd.h (remove, remove_all): Declare.
* src/c++17/fs_dir.cc (_Dir): Add filename_only parameter to
constructor. Pass file descriptor argument to base constructor.
(_Dir::dir_and_pathname, _Dir::open_subdir, _Dir::do_unlink)
(_Dir::unlink, _Dir::rmdir): Define new member functions.
(directory_iterator): Pass filename_only argument to _Dir
constructor.
(recursive_directory_iterator::_Dir_stack): Adjust constructor
parameters to take a _Dir rvalue instead of creating one.
(_Dir_stack::orig): Add data member for storing original path.
(_Dir_stack::report_error): Define new member function.
(__directory_iterator_nofollow): Move here from dir-common.h and
fix value to be a power of two.
(__directory_iterator_filename_only): Define new constant.
(recursive_directory_iterator): Construct _Dir object and move
into _M_dirs stack. Pass skip_permission_denied argument to first
advance call.
(recursive_directory_iterator::increment): Use _Dir::open_subdir.
(recursive_directory_iterator::__erase): Define new member
function.
* src/c++17/fs_ops.cc (ErrorReporter, do_remove_all): Remove.
(fs::remove_all): Use new recursive_directory_iterator::__erase
member function.
* src/filesystem/dir-common.h (_Dir_base): Add int parameter to
constructor and use openat to implement nofollow semantics.
(_Dir_base::fdcwd, _Dir_base::set_close_on_exec, _Dir_base::openat):
Define new member functions.
(__directory_iterator_nofollow): Move to fs_dir.cc.
* src/filesystem/dir.cc (_Dir): Pass file descriptor argument to
base constructor.
(_Dir::dir_and_pathname, _Dir::open_subdir): Define new member
functions.
(recursive_directory_iterator::_Dir_stack): Adjust constructor
parameters to take a _Dir rvalue instead of creating one.
(recursive_directory_iterator): Check for new nofollow option.
Construct _Dir object and move into _M_dirs stack. Pass
skip_permission_denied argument to first advance call.
(recursive_directory_iterator::increment): Use _Dir::open_subdir.
* src/filesystem/ops.cc (fs::remove_all): Use C++17 remove_all.
We should use the SUGGEST macro for std::uncaught_exception()
deprecation warnings.
libstdc++-v3/ChangeLog:
* include/bits/allocator.h: Qualify std::allocator_traits in
deprecated warnings.
* libsupc++/exception (uncaught_exception): Add suggestion to
deprecated warning.
The C++98-style concept check for output iterators causes a link
failure on mingw-w64, because the __val() member function isn't defined.
Change it to use a function pointer instead. That pointer is never set
to anything meaningful, but it doesn't matter as the __constraints()
function only has to be instantiated, it's never called.
We could refactor all of these to use unevaluated contexts (e.g. sizeof
of __decltype) so that we only check the expressions are well-formed,
without any codegen at all. Any improvements to these are very low
priority though.
libstdc++-v3/ChangeLog:
* include/bits/boost_concept_check.h (_OutputIteratorConcept):
Change member function to data member of function pointer type.
This matches the memory order in libc++.
libstdc++-v3/ChangeLog:
* include/bits/atomic_wait.h: Change memory order from
Acquire/Release with relaxed loads to SeqCst+Release for
accesses to the waiter's count.
The compiler warns about the loop in deque::_M_range_initialize because
it doesn't know that the number of nodes has already been correctly
sized to match the size of the input. Use __builtin_unreachable to tell
it that the loop will never be entered if the number of elements is
smaller than a single node.
libstdc++-v3/ChangeLog:
PR libstdc++/100516
* include/bits/deque.tcc (_M_range_initialize<ForwardIterator>):
Add __builtin_unreachable to loop.
* testsuite/23_containers/deque/100516.cc: New test.
When (bound - i) or n is the most negative value of its type, the
negative of the value will overflow. Instead of abs(n) >= abs(bound - i)
use n >= (bound - i) when positive and n <= (bound - i) when negative.
The function has a precondition that they must have the same sign, so
this works correctly. The precondition check can be moved into the else
branch, and simplified.
The standard requires calling ranges::advance(i, bound) even if i==bound
is already true, which is technically observable, but that's pointless.
We can just return n in that case. Similarly, for i!=bound but n==0 we
are supposed to call ranges::advance(i, n), but that's pointless. An LWG
issue to allow omitting the pointless calls is expected to be filed.
libstdc++-v3/ChangeLog:
* include/bits/ranges_base.h (ranges::advance): Avoid signed
overflow. Do nothing if already equal to desired result.
* testsuite/24_iterators/range_operations/advance_overflow.cc:
New test.
With -fno-exceptions we get a -Wmisleading-indentation warning for:
if (cond)
__try {}
__catch (...) {}
This is because the __catch(...) expands to if (false), but is indented
as though it is controlled by the preceding 'if'. Surround it in braces.
The new make_shared<T[]> code triggers a bogus warning due to PR 61596,
which can be disabled with a pragma.
libstdc++-v3/ChangeLog:
PR libstdc++/104019
* include/bits/istream.tcc (basic_istream::sentry): Add braces
around try-block.
* include/bits/shared_ptr_base.h (_Sp_counted_array_base::_M_init):
Add pragmas to disable bogus warnings from PR 61596.
libstdc++-v3/ChangeLog:
PR libstdc++/104032
* include/std/spanstream (basic_spanbuf(basic_spanbuf&&)): Use
mem-initializer for _M_buf.
(basic_spanbuf::Operator=(basic_spanbuf&&)): Fix ill-formed
member access.
* testsuite/27_io/spanstream/2.cc: New test.
I broke this unintentionally in r12-4259.
libstdc++-v3/ChangeLog:
PR libstdc++/104174
* include/bits/hashtable_policy.h (_Map_base): Add partial
specialization for maps with const key types.
* testsuite/23_containers/unordered_map/104174.cc: New test.
The non-atomic store that sets both reference counts to zero uses a
type-punned pointer, which has undefined behaviour. We could use memset
to write 8 bytes, but we don't actually need it to be a single store
anyway. No other thread can observe the values, that's why it's safe to
use non-atomic stores in the first place. So we can just set each count
to zero.
With -fstore-merging (which is enabled by default at -O2) GCC produces
the same code for this as for memset or the type punned store. Clang
does that store merging even at -O1.
libstdc++-v3/ChangeLog:
PR libstdc++/104019
* include/bits/shared_ptr_base.h (_Sp_counted_base<>::_M_release):
Set members to zero without type punning.
I changed the preprocessor condition from <= to < in r12-6574 which
meant the macro was not defined by <version> for C++17.
libstdc++-v3/ChangeLog:
* include/std/version (__cpp_lib_shared_ptr_arrays): Fix
condition for C++17 definition.
Use SFINAE magic to support: "It is unspecified whether math_errhandling
is a macro or an identifier with external linkage." [C Standard]
Signed-off-by: Matthias Kretz <m.kretz@gsi.de>
libstdc++-v3/ChangeLog:
* include/experimental/bits/simd.h (__floating_point_flags): Do
not rely on math_errhandling to expand to a constant expression.
This was deprecated in C++17, not C++14.
libstdc++-v3/ChangeLog:
* include/bits/stl_tempbuf.h (get_temporary_buffer): Change
_GLIBCXX14_DEPRECATED to _GLIBCXX17_DEPRECATED.
This function is no longer used since r12-6691 and can be removed.
libstdc++-v3/ChangeLog:
* include/bits/stl_pair.h (_PCC::_DeprConsPair): Remove unused
function.
This fixes an on AIX.
The lock function currently just spins, which should be changed to use
back-off, and maybe then _M_val.wait(__current) when supported.
libstdc++-v3/ChangeLog:
PR libstdc++/104101
* include/bits/shared_ptr_atomic.h (_Sp_atomic::_Atomic_count::lock):
Only use __thread_relax if __cpp_lib_atomic_wait is defined.
The new deleted constructors added by P2166R1 are a breaking change,
making previously valid code ill-formed in C++23. As a result, they
should only be defined for C++23 and not for C++11 and up.
libstdc++-v3/ChangeLog:
PR libstdc++/104099
* include/bits/basic_string.h (basic_string(nullptr_t)): Only
define for C++23.
(operator=(nullptr_t)): Likewise.
* include/bits/cow_string.h: Likewise.
* include/std/string_view (basic_string_view(nullptr_t)):
Likewise.
* testsuite/21_strings/basic_string/cons/char/nullptr.cc: Adjust
expected error. Add examples that become ill-formed in C++23.
* testsuite/21_strings/basic_string_view/cons/char/nonnull.cc:
Adjust expected errors.
* testsuite/21_strings/basic_string_view/cons/wchar_t/nonnull.cc:
Likewise.
We should not assume that std::iter_value_t etc. are defined
unconditionally for C++20 mode.
libstdc++-v3/ChangeLog:
PR libstdc++/104098
* include/bits/stl_iterator.h (reverse_iterator): Check
__cpp_lib_concepts instead of __cplusplus.
The deprecated non-standard std::pair constructors that allow
constructing std::pair<move-only-type, pointer-type> from an rvalue and
a literal zero where not sufficiently constrained. They were viable when
constructing std::pair<copyable-type, pointer-type>, and that case
should work fine using the standard constructors.
Replace the constraints on the non-standard constructors so they are
only viable in cases that should actually be ill-formed according to the
standard.
Also rename __null_ptr_constant to __zero_as_null_pointer_constant so it
matches the name of the -Wzero-as-null-pointer-constant warning. Also
make the text of the deprecated warning describe the problem in more
detail.
libstdc++-v3/ChangeLog:
PR libstdc++/101124
* include/bits/stl_pair.h (pair): Adjust constraints on
deprecated constructors accepting literal zero as null pointer
constant. Improve wording of deprecated attribute.
* testsuite/20_util/pair/cons/99957.cc: Check that deprecated
constructors do not cause ambiguities for copyable types.
This patch completes implementation of the C++20 proposal P0482R6 [1] by
adding declarations of std::c8rtomb() and std::mbrtoc8() in <cuchar> if
provided by the C library in <uchar.h>.
This patch addresses feedback provided in response to a previous patch
submission [2].
Autoconf changes determine if the C library declares c8rtomb and mbrtoc8
at global scope when uchar.h is included and compiled with either
-fchar8_t or -std=c++20. New _GLIBCXX_USE_UCHAR_C8RTOMB_MBRTOC8_FCHAR8_T
and _GLIBCXX_USE_UCHAR_C8RTOMB_MBRTOC8_CXX20 configuration macros
reflect the probe results. The <cuchar> header declares these functions
in the std namespace only if available and the _GLIBCXX_USE_CHAR8_T
configuration macro is defined (by default it is defined if the C++20
__cpp_char8_t feature test macro is defined)
Patches to glibc to implement c8rtomb and mbrtoc8 have been submitted [3].
New tests validate the presence of these declarations. The tests pass
trivially if the C library does not provide these functions. Otherwise
they ensure that the functions are declared when <cuchar> is included
and either -fchar8_t or -std=c++20 is enabled.
1]: WG21 P0482R6
"char8_t: A type for UTF-8 characters and strings (Revision 6)"
https://wg21.link/p0482r6
[2]: [PATCH] C++ P0482R6 char8_t: declare std::c8rtomb and std::mbrtoc8
if provided by the C library
https://gcc.gnu.org/pipermail/libstdc++/2021-June/052685.html
[3]: "C++20 P0482R6 and C2X N2653"
[Patch 0/3]:
https://sourceware.org/pipermail/libc-alpha/2022-January/135061.html
[Patch 1/3]:
https://sourceware.org/pipermail/libc-alpha/2022-January/135062.html
[Patch 2/3]:
https://sourceware.org/pipermail/libc-alpha/2022-January/135063.html
[Patch 3/3]:
https://sourceware.org/pipermail/libc-alpha/2022-January/135064.html
libstdc++-v3/ChangeLog:
* acinclude.m4: Define config macros if uchar.h provides
c8rtomb() and mbrtoc8().
* config.h.in: Regenerate.
* configure: Regenerate.
* include/c_compatibility/uchar.h (c8rtomb, mbrtoc8): Define.
* include/c_global/cuchar (c8rtomb, mbrtoc8): Likewise.
* include/c_std/cuchar (c8rtomb, mbrtoc8): Likewise.
* testsuite/21_strings/headers/cuchar/functions_std_cxx20.cc:
New test.
* testsuite/21_strings/headers/cuchar/functions_std_fchar8_t.cc:
New test.
This adds the C++23 <stdatomic.h> header, as proposed by P0943R6, for
compatibility with C code.
There are still some ABI differences between atomic_xxx in C and C++
std::atomic_xxx in C++, so this only provides source compatibility, not
binary compatibility.
libstdc++-v3/ChangeLog:
* include/Makefile.am: Install new header.
* include/Makefile.in: Regenerate.
* include/c_compatibility/stdatomic.h: New file.
* testsuite/29_atomics/headers/stdatomic.h/c_compat.cc: New test.
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.
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.
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.
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 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.
