2019-03-06 Edward Smith-Rowland <3dw4rd@verizon.net>
PR libstdc++/86655 - std::assoc_legendre should not constrain
the value of m (or x).
* include/tr1/legendre_function.tcc (__assoc_legendre_p,
__sph_legendre): If degree > order Don't throw, return 0.
(__legendre_p, __assoc_legendre_p): Don't constrain x either.
* testsuite/special_functions/02_assoc_legendre/pr86655.cc: New test.
* testsuite/special_functions/20_sph_legendre/pr86655.cc: New test.
* testsuite/tr1/5_numerical_facilities/special_functions/
02_assoc_legendre/pr86655.cc: New test.
* testsuite/tr1/5_numerical_facilities/special_functions/
22_sph_legendre/pr86655.cc: New test.
From-SVN: r269423
* include/std/variant (__do_visit): New.
(__variant_cast): Likewise.
(__variant_cookie): Likewise.
(__erased_*): Remove.
(_Variant_storage::_S_vtable): Likewise.
(_Variant_storage::__M_reset_impl): Adjust to use __do_visit.
(_Variant_storage::__M_reset): Adjust.
(__variant_construct): New.
(_Copy_ctor_base(const _Copy_ctor_base&)): Adjust to use
__variant_construct.
(_Move_ctor_base(_Move_ctor_base&&)): Likewise.
(_Move_ctor_base::__M_destructive_copy): New.
(_Move_ctor_base::__M_destructive_move): Adjust to use
__variant_construct.
(_Copy_assign_base::operator=): Adjust to use __do_visit.
(_Copy_assign_alias): Adjust to check both copy assignment
and copy construction for triviality.
(_Move_assign_base::operator=): Adjust to use __do_visit.
(_Multi_array): Add support for visitors that accept and return
a __variant_cookie.
(__gen_vtable_impl::_S_apply_all_alts): Likewise.
(__gen_vtable_impl::_S_apply_single_alt): Likewise.
(__gen_vtable_impl::__element_by_index_or_cookie): New. Generate
a __variant_cookie temporary for a variant that is valueless and..
(__gen_vtable_impl::__visit_invoke): ..adjust here.
(__gen_vtable::_Array_type): Conditionally make space for
the __variant_cookie visitor case.
(__variant_construct_by_index): New.
(get_if): Adjust to use std::addressof.
(relops): Adjust to use __do_visit.
(variant): Add __variant_cast and __variant_construct_by_index
as friends.
(variant::emplace): Use _M_reset() and __variant_construct_by_index
instead of self-destruction.
(variant::swap): Adjust to use __do_visit.
(visit): Reimplement in terms of __do_visit.
(__variant_hash_call_base_impl::operator()): Adjust to use __do_visit.
* testsuite/20_util/variant/compile.cc: Adjust.
* testsuite/20_util/variant/run.cc: Likewise.
From-SVN: r269422
The implementation of midpoint used for integral types is due to Howard
Hinnant and avoids a branch for int and larger types (but not for chars
and shorts).
The midpoint and lerp functions for floating point types come straight
from the P0811R3 proposal, with no attempt at optimization.
* include/c_compatibility/math.h [C++20] (lerp): Add using
declaration.
* include/c_global/cmath [C++20] (__cpp_lib_interpolate): Define.
(__lerp): Define function template to implement lerp.
(lerp(float, float, float), lerp(double, double, double))
(lerp(long double, long double, long double)): Define for C++20.
* include/std/numeric [C++20] (__cpp_lib_interpolate): Define.
(midpoint(T, T), midpoint(T*, T*)): Define.
* include/std::version [C++20] (__cpp_lib_interpolate): Define.
* testsuite/26_numerics/lerp.cc: New test.
* testsuite/26_numerics/midpoint/floating.cc: New test.
* testsuite/26_numerics/midpoint/integral.cc: New test.
* testsuite/26_numerics/midpoint/pointer.cc: New test.
From-SVN: r269398
2019-03-04 Edward Smith-Rowland <3dw4rd@verizon.net>
PR libstdc++/88996 Implement P0439R0
Make std::memory_order a scoped enumeration.
* include/bits/atomic_base.h: For C++20 make memory_order a scoped enum,
add variables for the old enumerators. Adjust calls.
* testsuite/29_atomics/headers/atomic/types_std_c++2a.cc: New test.
* testsuite/29_atomics/headers/atomic/types_std_c++2a_neg.cc: New test.
From-SVN: r269372
* include/std/memory (uses_allocator_construction_args): New set of
overloaded functions.
(make_obj_using_allocator, uninitialized_construct_using_allocator):
New functions.
* include/std/memory_resource (polymorphic_allocator::construct)
[__cplusplus > 201703l]: Replace all overloads with a single function
using uses_allocator_construction_args.
* testsuite/20_util/polymorphic_allocator/construct_c++2a.cc: New
test.
* testsuite/20_util/uses_allocator/make_obj.cc: New test.
From-SVN: r269311
Certain broken versions of xsltproc ignore the --nonet option and will
attempt to fetch the docbook stylesheet from the WWW when it isn't in
the local XML catalog.
This patch checks for the local stylesheet directory first, and doesn't
use xsltproc if no local stylesheets are found. Checking for the local
directory is done using xmlcatalog if available, only checking the
hardcoded list of directories if xmlcatalog fails. The right directory
for Suse is added to the hardcoded list.
This should avoid doing an xsltproc check that would need to download
the stylesheet, so no network connection is made even if a broken
xsltproc is present.
PR libstdc++/89466
* acinclude.m4 (GLIBCXX_CONFIGURE_DOCBOOK): Reorder check for local
stylesheet directories before check for xsltproc. Try to use
xmlcatalog to find local stylesheet directory before trying hardcoded
paths. Add path used by suse to hardcoded paths. Adjust xsltproc
check to look for the same stylesheet as doc/Makefile.am uses. Don't
use xsltproc if xmlcatalog fails to find a local stylesheet.
* configure.ac: Check for xmlcatalog.
* Makefile.in: Regenerate.
* configure: Likewise.
* doc/Makefile.in: Likewise.
* include/Makefile.in: Likewise.
* libsupc++/Makefile.in: Likewise.
* po/Makefile.in: Likewise.
* python/Makefile.in: Likewise.
* src/Makefile.in: Likewise.
* src/c++11/Makefile.in: Likewise.
* src/c++17/Makefile.in: Likewise.
* src/c++98/Makefile.in: Likewise.
* src/filesystem/Makefile.in: Likewise.
* testsuite/Makefile.in: Likewise.
From-SVN: r269249
The Compare, Hash, and Pred template parameters should be constrained in
the C++17 deduction guides for associative and unordered containers.
The deduction guides for stack, queue and priority_queue are already
constrained, but this patch makes them use the _RequireNotAllocator
helper instead of reproducing the logic each time.
PR libstdc++/89477
* include/bits/alloc_traits.h (_RequireNotAllocator): New helper for
container deduction guides.
* include/bits/hashtable.h (_RequireNotAllocatorOrIntegral): Likewise.
* include/bits/stl_map.h (map): Use _RequireNotAllocator to constrain
parameters in deduction guides.
* include/bits/stl_multimap.h (multimap): Likewise.
* include/bits/stl_multiset.h (multiset): Likewise.
* include/bits/stl_queue.h (queue, priority_queue): Likewise.
* include/bits/stl_set.h (set): Likewise.
* include/bits/stl_stack.h (stack): Likewise.
* include/bits/unordered_map.h (unordered_map, unordered_multimap):
use _RequireNotAllocator and _RequireNotAllocatorOrIntegral to
constrain parameters in deduction guides.
* include/bits/unordered_set.h (unordered_set, unordered_multiset):
Likewise.
* testsuite/23_containers/map/cons/deduction.cc: Test additional
deduction cases.
* testsuite/23_containers/multiset/cons/deduction.cc: Likewise.
* testsuite/23_containers/set/cons/deduction.cc: Likewise.
* testsuite/23_containers/unordered_map/cons/deduction.cc: Likewise.
* testsuite/23_containers/unordered_multimap/cons/deduction.cc:
Likewise.
* testsuite/23_containers/unordered_multiset/cons/deduction.cc:
Likewise.
* testsuite/23_containers/unordered_set/cons/deduction.cc: Likewise.
From-SVN: r269234
PR libstdc++/89416
* include/bits/alloc_traits.h (__is_alloc_insertable_impl): Change
to class template and partial specialization using void_t.
(__is_copy_insertable, __is_move_insertable): Adjust base class.
From-SVN: r269229
* include/std/type_traits (__underlying_type_impl): New helper to
make underlying_type SFINAE-friendly.
(underlying_type): Derive from __underlying_type_impl.
* testsuite/20_util/underlying_type/requirements/typedefs-3.cc: New
test.
From-SVN: r269168
PR libstdc++/89446
* include/bits/char_traits.h (__constant_char_array): Check index is
in range before dereferencing.
(char_traits<char>::compare, char_traits<char>::find)
(char_traits<char8_t>::compare, char_traits<char8_t>::find): Return
immediately if n is zero.
(char_traits<wchar_t>::compare, char_traits<wchar_t>::find): Likewise.
Remove workarounds for PR 67026.
* testsuite/21_strings/basic_string_view/operators/char/89446.cc:
New test.
* testsuite/21_strings/basic_string_view/operators/wchar_t/89446.cc:
New test.
From-SVN: r269148
This patch corrects ambiguous partial specializations of
typelist::detail::append_. Previously, neither append_<chain<Hd, Tl>,
Typelist_Chain> nor append_<Typelist_Chain, null_type> was a better
match for append_<chain<Hd, Tl>, null_type>.
2019-02-22 Tom Honermann <tom@honermann.net>
* include/ext/typelist.h: Constrain a partial specialization of
typelist::detail::append_ to only match chain<T1,T2>.
From-SVN: r269088
The common base class for __is_move_insertable and __is_copy_insertable
instantiates both the copy and move tests, when only one is needed. The
unneeded one might cause errors outside the immediate context.
The solution used in this patch is to replace them with alias templates,
which will only be instantiated as needed.
PR libstdc++/89416
* include/bits/alloc_traits.h (__is_alloc_insertable_impl): Replace
class template with class. Replace move and copy member types with
member alias templates, so they are only instantiated when needed.
(__is_copy_insertable, __is_move_insertable): Adjust base class.
* testsuite/23_containers/vector/modifiers/push_back/89130.cc: Enable
test for C++11/14/17 as well.
* testsuite/23_containers/vector/modifiers/push_back/89416.cc: New
test.
From-SVN: r269075
Because uses-allocator construction is invariably done with a const
lvalue the __uses_alloc helper should use a const lvalue for the
is_constructible checks. Otherwise, it can detect that the type can be
constructed from an rvalue, and then an error happens when a const
lvalue is passed to the constructor instead.
Prior to LWG DR 2586 scoped_allocator_adaptor incorrectly used an rvalue
type in the is_constructible check and then used a non-const lvalue for
the actual construction. The other components using uses-allocator
construction (tuple and polymorphic_allocator) have always done so with
a const lvalue allocator, although the use of __use_alloc in our
implementation meant they behaved the same as scoped_allocator_adaptor
and incorrectly used rvalues for the is_constructible checks.
In C++20 the P0591R4 changes mean that all uses-allocator construction
is defined in terms of the new uses_allocator_construction_args
functions, which always use a const lvalue allocator.
The changes in this patch ensure that the __use_alloc helper correctly
matches the requirements in the standard, consistently using a const
lvalue allocator for the is_constructible checks and the actual
constructor arguments.
* doc/xml/manual/intro.xml: Document LWG 2586 status.
* include/bits/uses_allocator.h (__uses_alloc): Use const lvalue
allocator type in is_constructible checks.
* testsuite/20_util/scoped_allocator/69293_neg.cc: Adjust dg-error.
* testsuite/20_util/scoped_allocator/dr2586.cc: New test.
* testsuite/20_util/tuple/cons/allocators.cc: Add test using
problematic type from LWG 2586 discussion.
* testsuite/20_util/uses_allocator/69293_neg.cc: Adjust dg-error.
* testsuite/20_util/uses_allocator/cons_neg.cc: Likewise.
From-SVN: r268882
This change is safe to make now (in stage 4), because the constructors
are currently incorrect and unusable (unless the supplied container
already contains a heap, in which case the new make_heap calls are
redundant but harmless).
* doc/xml/manual/intro.xml: Document LWG 2537 status.
* include/bits/stl_queue.h
(priority_queue(const Compare&, const Container&, const Alloc&))
(priority_queue(const Compare&, Container&&, const Alloc&)): Call
make_heap.
* testsuite/23_containers/priority_queue/dr2537.cc: New test.
From-SVN: r268878
Although there is no good use for stack<int, deque<double>> or similar
types with a mismatched value_type, it's possible somebody is doing that
and getting away with it currently. This patch only enforces the new
requirement for C++17 and later. During stage 1 we should consider
enforcing it for C++11 and C++14.
* doc/xml/manual/intro.xml: Document LWG 2566 status.
* include/bits/stl_queue.h (queue, priority_queue): Add static
assertions to enforce LWG 2566 requirement on value_type.
* include/bits/stl_stack.h (stack): Likewise.
From-SVN: r268877
This DR was already resolved for GCC 7.1 by the implementation of DR
2192, but we didn't have an explicit test for the behaviour that 2735
guarantees.
* doc/xml/manual/intro.xml: Document LWG 2735 status.
* include/bits/std_abs.h: Add comment about LWG 2735.
* testsuite/26_numerics/headers/cstdlib/dr2735.cc: New test.
From-SVN: r268867
Clang defines the __cpp_impl_destroying_delete macro unconditionally, so
that the feature is supported whenever the library type is defined. This
is incompatible with the current definition in libstdc++ because we use
constexpr and inline variables, which will give an error for older -std
modes.
This patch defines the destroying_delete_t type and destroying_delete
variable independently of the __cpp_impl_destroying_delete macro, but
only for C++2a (because the names aren't reserved for previous
standards). The __cpp_lib_destroying_delete macro is only defined when
both the library type and compiler macro are defined (i.e. when the type
can actually be used as intended).
PR libstdc++/89345
* include/std/version [__cpp_impl_destroying_delete]
(__cpp_lib_destroying_delete): Only define for C++2a and later.
* libsupc++/new [__cpp_impl_destroying_delete]
(__cpp_lib_destroying_delete): Likewise.
(destroying_delete_t, destroying_delete): Likewise, but define even
when __cpp_impl_destroying_delete is not defined.
* testsuite/18_support/destroying_delete.cc: New test.
From-SVN: r268856
In the standard these member functions are specified in terms of the
potentially-throwing path decompositions functions, but we implement
them without constructing any new paths or doing anything else that can
throw.
PR libstdc++/71044
* include/bits/fs_path.h (path::has_root_name)
(path::has_root_directory, path::has_root_path)
(path::has_relative_path, path::has_parent_path)
(path::has_filename, path::has_stem, path::has_extension)
(path::is_absolute, path::is_relative, path::_M_find_extension): Add
noexcept.
* src/c++17/fs_path.cc (path::has_root_name)
(path::has_root_directory, path::has_root_path)
(path::has_relative_path, path::has_parent_path)
(path::has_filename, path::_M_find_extension): Add noexcept.
From-SVN: r268713
This is a partial implementation of the revised std::common_type rules
from P0435R1.
PR libstdc++/89102 (partial)
* include/std/type_traits (common_type<>): Define.
(common_type<T>): Derive from common_type<T, T>.
* testsuite/20_util/common_type/requirements/explicit_instantiation.cc:
Test zero-length template argument list.
* testsuite/20_util/common_type/requirements/sfinae_friendly_1.cc:
Test additional single argument cases.
* testsuite/20_util/common_type/requirements/sfinae_friendly_2.cc:
Adjust expected error.
From-SVN: r268586
The additional logic added to __is_convertible_helper in order to
support is_nothrow_convertible makes some uses of is_convertible
ill-formed. This appears to be due to PR c++/87603, but can be avoided
just by defining a separate helper for is_nothrow_convertible. The same
problems are likely to still exist for is_nothrow_convertible, but that
is new and so won't cause regressions for existing users of
is_convertible.
PR libstdc++/89194
* include/std/type_traits (__is_convertible_helper)
(__is_convertible_helper<_From, _To, false>): Revert changes to
support is_nothrow_convertible.
(__is_nt_convertible_helper): New helper.
(is_nothrow_convertible): Use __is_nt_convertible_helper.
From-SVN: r268543
The changes to "relocate" std::vector elements can lead to new errors
outside the immediate context, because moving the elements to new
storage no longer makes use of the move-if-noexcept utilities. This
means that types with deleted moves no longer degenerate to copies, but
are just ill-formed. The errors happen while instantiating the
noexcept-specifier for __relocate_object_a, when deciding whether to try
to relocate.
This patch introduces indirections to avoid the ill-formed
instantiations of std::__relocate_object_a. In order to avoid using
if-constexpr prior to C++17 this is done by tag dispatching. After this
patch all uses of std::__relocate_a are guarded by checks that will
support sensible code (i.e. code not using custom allocators that fool
the new checks).
PR libstdc++/89130
* include/bits/alloc_traits.h (__is_copy_insertable_impl): Rename to
__is_alloc_insertable_impl. Replace single type member with two
members, one for each of copy and move insertable.
(__is_move_insertable): New trait for internal use.
* include/bits/stl_vector.h (vector::_S_nothrow_relocate(true_type))
(vector::_S_nothrow_relocate(true_type)): New functions to
conditionally check if __relocate_a can throw.
(vector::_S_use_relocate()): Dispatch to _S_nothrow_relocate based
on __is_move_insertable.
(vector::_S_do_relocate): New overloaded functions to conditionally
call __relocate_a.
(vector::_S_relocate): New function that dispatches to _S_do_relocate
based on _S_use_relocate.
* include/bits/vector.tcc (vector::reserve, vector::_M_realloc_insert)
(vector::_M_default_append): Call _S_relocate instead of __relocate_a.
* testsuite/23_containers/vector/modifiers/push_back/89130.cc: New.
From-SVN: r268537
Although GCC and Clang both allow these features pre-C++17 in system
headers, Clang does issue warnings with -Wsystem-headers. It can also
complicate bisection and/or testcase reduction if # line markers are
stripped, because the code won't be known to come from system headers.
PR libstdc++/89090
* include/bits/stl_uninitialized.h (__relocate_a_1): Make unused
parameter unnamed. Add message to static assertion.
* include/bits/vector.tcc (vector::reserve, vector::_M_realloc_insert)
(vector::_M_default_append): Use _GLIBCXX17_CONSTEXPR for if constexpr
in C++11 code.
From-SVN: r268536
These calls should have been qualified to avoid ADL anyway, but in C++2a
it becomes essential to qualify the calls in experimental::erase because
std::erase_if is also declared and the calls become ambiguous.
* include/experimental/forward_list (experimental::erase): Qualify
call to erase_if.
* include/experimental/list (experimental::erase): Likewise.
* include/std/forward_list (std::erase): Likewise.
* include/std/list (std::erase): Likewise.
From-SVN: r268356
The __pool_resource::_M_unpooled member was declared with type
std::vector, which means that the type depends on whether debug mode is
active or not. Because the non-inline definitions in
src/c++17/memory_resource.cc are never compiled with debug mode, the
type declared in the header doesn't match the type in the library
definitions, leading to undefined behaviour.
The solution is to ensure the header always uses the non-debug vector,
even when debug mode is active. To make this easier a new alias template
is defined: _GLIBCXX_STD_C::pmr::vector.
* include/std/memory_resource (__pool_resource::_M_unpooled): Use
normal mode vector, even for debug mode.
* include/std/vector [_GLIBCXX_DEBUG] (_GLIBCXX_STD_C::pmr::vector):
Define alias template for normal mode vector.
From-SVN: r268354
It doesn't conform to the spec, so use vsprintf with a large buffer
instead.
PR libstdc++/68737
* config/locale/generic/c_locale.h (__convert_from_v)
[_GLIBCXX_USE_C99_STDIO]: Also check _GLIBCXX_HAVE_BROKEN_VSNPRINTF.
* config/os/hpux/os_defines.h: Define _GLIBCXX_HAVE_BROKEN_VSNPRINTF.
* include/bits/locale_facets.tcc (num_put::_M_insert_float)
[_GLIBCXX_USE_C99_STDIO]: Also check _GLIBCXX_HAVE_BROKEN_VSNPRINTF.
From-SVN: r268350
Clang fails to compile std::vector<Incomplete> because the static member
__use_relocate cannot be evaluated for an incomplete type. Replace with
a static member function that will not be odr-used until needed, by
which point the type must be complete.
PR libstdc++/88840
* include/bits/stl_vector.h (vector::__use_relocate): Replace static
data member with static member function _S_use_relocate().
* include/bits/vector.tcc (vector::reserve, vector::_M_realloc_insert)
(vector::_M_default_append): Use _S_use_relocate() instead of
__use_relocate.
From-SVN: r268239
The old version of _Sp_counted_ptr_inplace::_M_get_deleter (up to GCC
8.2.0) expects to be passed a real std::typeinfo object, so mixing that
with the new definition of the __shared_ptr constructor (which always
passes the fake tag) leads to accessing the fake object as a real
std::typeinfo. Instead of trying to make it safe to mix the old and new
definitions, just stop using that function. By passing a reference to
__shared_ptr::_M_ptr to the __shared_count constructor it can be set
directly, without needing to obtain the pointer via the _M_get_deleter
back-channel. This avoids a virtual dispatch (which fixes PR 87514).
This means that code built against new libstdc++ headers doesn't use
_M_get_deleter at all, and so make_shared works the same whether RTTI is
enabled or not.
Also change _M_get_deleter so that it checks for a real type_info object
even when RTTI is disabled, by calling a library function. Unless
libstdc++ itself is built without RTTI that library function will be
able to test if it's the right type_info. This means the new definition
of _M_get_deleter can handle both the fake type_info tag and a real
type_info object, even if built without RTTI.
If linking to objects built against older versions of libstdc++ then if
all objects use -frtti or all use -fno-rtti, then the caller of
_M_get_deleter and the definition of _M_get_deleter will be consistent
and it will work. If mixing -frtti with -fno-rtti it can still fail if
the linker picks an old definition of _M_get_deleter and an old
__shared_ptr constructor that are incompatible. In that some or all
objects might need to be recompiled.
PR libstdc++/87514
PR libstdc++/87520
PR libstdc++/88782
* config/abi/pre/gnu.ver (GLIBCXX_3.4.26): Export new symbol.
* include/bits/shared_ptr.h
(shared_ptr(_Sp_make_shared_tag, const Alloc&, Args&&...))
(allocate_shared): Change to use new tag type.
* include/bits/shared_ptr_base.h (_Sp_make_shared_tag::_S_eq):
Declare new member function.
(_Sp_alloc_shared_tag): Define new type.
(_Sp_counted_ptr_inplace): Declare __shared_count<_Lp> as a friend.
(_Sp_counted_ptr_inplace::_M_get_deleter) [!__cpp_rtti]: Use
_Sp_make_shared_tag::_S_eq to check type_info.
(__shared_count(Ptr, Deleter),__shared_count(Ptr, Deleter, Alloc)):
Constrain to prevent being called with _Sp_alloc_shared_tag.
(__shared_count(_Sp_make_shared_tag, const _Alloc&, Args&&...)):
Replace constructor with ...
(__shared_count(Tp*&, _Sp_alloc_shared_tag<_Alloc>, Args&&...)): Use
reference parameter so address of the new object can be returned to
the caller. Obtain the allocator from the tag type.
(__shared_ptr(_Sp_make_shared_tag, const Alloc&, Args&&...)): Replace
constructor with ...
(__shared_ptr(_Sp_alloc_shared_tag<Alloc>, Args&&...)): Pass _M_ptr
to the __shared_count constructor.
(__allocate_shared): Change to use new tag type.
* src/c++11/shared_ptr.cc (_Sp_make_shared_tag::_S_eq): Define.
From-SVN: r268086
PR libstdc++/88738
Warn about unused comparisons of shared_ptr/unique_ptr
* include/bits/c++config [_GLIBCXX_NODISCARD]: Define.
* include/bits/shared_ptr.h: Use it for operator ==, !=,
<, <=, >, >= for shared_ptr.
* include/bits/unique_ptr.h: Likewise for unique_ptr.
From-SVN: r267964
This patch implements the C++2a proposal to allow incomplete types in
std::reference_wrapper, which was previously undefined.
The change cannot be implemented for earlier standards, because prior to
C++2a std::reference_wrapper has a weak result type, so must inspect the
template argument to see if it defines a nested result_type member. That
is deprecated (but still required) in C++17, and removed from C++2a.
The removal of the base class from reference_wrapper is a potential ABI
change, as it could alter the layout of a type which derives from
reference_wrapper<T> and from an empty type with _Weak_result_type<T> as
a base class. Previously the repeated _Weak_result_type<T> base class
would have prevented the empty base-class optimization, but if
reference_wrapper<T> no longer derives from it, the empty class could be
placed at the same address as the reference_wrapper<T> base. In
practice, the only types which derive from _Weak_result_type or from
_Reference_wrapper_base_memfun or any of its base classes are non-empty
types defined in libstdc++: std::reference_wrapper, std::function, and
std::_Bind. As they are non-empty types, they are not eligible for EBO
anyway.
* include/bits/refwrap.h [__cplusplus > 201703L]
(_Refwrap_base_arg1, _Refwrap_base_arg2, _Reference_wrapper_base)
(_Reference_wrapper_base_memfun): Do not define for C++2a.
(reference_wrapper): Do not derive from _Reference_wrapper_base_memfun
for C++2a.
(reference_wrapper::operator()): Add static assertion.
* testsuite/20_util/reference_wrapper/incomplete.cc: New test.
From-SVN: r267866
This paper has been included in the C++20 draft, but the changes to add
noexcept can be made unconditionally, to apply for C++11 too.
* include/std/chrono (duration_values::zero(), duration_values::min())
(duration_values::max()): Add noexcept.
(duration::zero(), duration::min(), duration::max()): Likewise.
(time_point::zero(), time_point::min(), time_point::max()): Likewise.
* testsuite/20_util/duration/requirements/noexcept.cc: New test.
* testsuite/20_util/time_point/requirements/noexcept.cc: New test.
From-SVN: r267865
The C++2a draft specifies the value 201811L for this, but as an
extension we return the number of elements erased. This is expected to
be standardised, so the macro has the value 201900L until a proper value
is specified in the draft.
* include/bits/erase_if.h: Define __cpp_lib_erase_if.
* include/std/deque: Likewise.
* include/std/forward_list: Likewise.
* include/std/list: Likewise.
* include/std/string: Likewise.
* include/std/vector: Likewise.
* include/std/version: Likewise.
* testsuite/21_strings/basic_string/erasure.cc: Test macro.
* testsuite/23_containers/deque/erasure.cc: Likewise.
* testsuite/23_containers/forward_list/erasure.cc: Likewise.
* testsuite/23_containers/list/erasure.cc: Likewise.
* testsuite/23_containers/map/erasure.cc: Likewise.
* testsuite/23_containers/set/erasure.cc: Likewise.
* testsuite/23_containers/unordered_map/erasure.cc: Likewise.
* testsuite/23_containers/unordered_set/erasure.cc: Likewise.
* testsuite/23_containers/vector/erasure.cc: Likewise.
From-SVN: r267810
