Commit Graph

97 Commits

Author SHA1 Message Date
Jonathan Wakely
82b2e4f8cf libstdc++: Implement monadic operations for std::optional (P0798R8)
Another new addition to the C++23 working draft.

The new member functions of std::optional are only defined for C++23,
but the new members of _Optional_payload_base are defined for C++20 so
that they can be used in non-propagating-cache in <ranges>. The
_Optional_payload_base::_M_construct member can also be used in
non-propagating-cache now, because it's constexpr since r12-4389.

There will be an LWG issue about the feature test macro, suggesting that
we should just bump the value of __cpp_lib_optional instead. I haven't
done that here, but it can be changed once consensus is reached on the
change.

libstdc++-v3/ChangeLog:

	* include/std/optional (_Optional_payload_base::_Storage): Add
	constructor taking a callable function to invoke.
	(_Optional_payload_base::_M_apply): New function.
	(__cpp_lib_monadic_optional): Define for C++23.
	(optional::and_then, optional::transform, optional::or_else):
	Define for C++23.
	* include/std/ranges (__detail::__cached): Remove.
	(__detail::__non_propagating_cache): Remove use of __cached for
	contained value. Use _Optional_payload_base::_M_construct and
	_Optional_payload_base::_M_apply to set the contained value.
	* include/std/version (__cpp_lib_monadic_optional): Define.
	* testsuite/20_util/optional/monadic/and_then.cc: New test.
	* testsuite/20_util/optional/monadic/or_else.cc: New test.
	* testsuite/20_util/optional/monadic/or_else_neg.cc: New test.
	* testsuite/20_util/optional/monadic/transform.cc: New test.
	* testsuite/20_util/optional/monadic/version.cc: New test.
2021-10-19 15:01:16 +01:00
Jonathan Wakely
929abc7fe3 libstdc++: Define std::basic_string::resize_and_overwrite for C++23 (P1072R10)
A recently approved change for the C++23 working draft.

libstdc++-v3/ChangeLog:

	* include/bits/basic_string.h (__cpp_lib_string_resize_and_overwrite):
	Define for C++23.
	(basic_string::resize_and_overwrite): Declare.
	* include/bits/basic_string.tcc (basic_string::resize_and_overwrite):
	Define.
	* include/std/version (__cpp_lib_resize_and_overwrite): Define
	for C++23.
	* testsuite/21_strings/basic_string/capacity/char/resize_and_overwrite.cc:
	New test.
2021-10-16 00:44:16 +01:00
Jonathan Wakely
ad820b0bb5 libstdc++: Add missing constexpr to std::variant (P2231R1)
This implements the changes in P2231R1 which make std::variant fully
constexpr in C++20.

We need to replace placement new with std::construct_at, but that isn't
defined for C++17. Use std::_Construct instead, which forwards to
std::construct_at in C++20 mode (since the related changes to make
std::optional fully constexpr, in r12-4389).

We also need to replace the untyped char buffer in _Uninitialized with a
union, which can be accessed in constexpr functions. But the union needs
to have a non-trivial destructor if its variant type is non-trivial,
which means that the _Variadic_union also needs a non-trivial
destructor. This adds a constrained partial specialization of
_Variadic_union for the C++20-only case where a non-trivial destructor
is needed.

We can't use concepts to constrain the specialization (or the primary
template's destructor) in C++17, so retain the untyped char buffer
solution for C++17 mode.

libstdc++-v3/ChangeLog:

	* include/std/variant (__cpp_lib_variant): Update value for
	C++20.
	(__variant_cast, __variant_construct): Add constexpr for C++20.
	(__variant_construct_single, __construct_by_index) Likewise. Use
	std::_Construct instead of placement new.
	(_Uninitialized<T, false>) [__cplusplus >= 202002]: Replace
	buffer with a union and define a destructor.
	(_Variadic_union) [__cplusplus >= 202002]: Add a specialization
	for non-trivial destruction.
	(_Variant_storage::__index_of): New helper variable template.
	(_Variant_storage::~_Variant_storage()): Add constexpr.
	(_Variant_storage::_M_reset()): Likewise.
	(_Copy_ctor_base, _Move_ctor_base): Likewise.
	(_Copy_assign_base, _Move_assign_base): Likewise.
	(variant, swap): Likewise.
	* include/std/version (__cpp_lib_variant): Update value for
	C++20.
	* testsuite/20_util/optional/version.cc: Check for exact value
	in C++17.
	* testsuite/20_util/variant/87619.cc: Increase timeout for
	C++20 mode.
	* testsuite/20_util/variant/constexpr.cc: New test.
	* testsuite/20_util/variant/version.cc: New test.
2021-10-15 18:26:53 +01:00
Jonathan Wakely
476f305b6c libstdc++: Add missing constexpr to std::optional (P2231R1)
This implements the changes in P2231R1 which make std::optional fully
constexpr in C++20.

libstdc++-v3/ChangeLog:

	* include/bits/stl_construct.h (_Construct): Use
	std::construct_at when constant evaluated.
	* include/std/optional (_Storage, _Optional_payload, optional):
	Add constexpr as specified by P2231R1.
	* include/std/version (__cpp_lib_optional): Update value for
	C++20.
	* testsuite/20_util/optional/requirements.cc: Check feature test
	macro.
	* testsuite/20_util/optional/constexpr/assign.cc: New test.
	* testsuite/20_util/optional/constexpr/cons/conv.cc: New test.
	* testsuite/20_util/optional/constexpr/modifiers.cc: New test.
	* testsuite/20_util/optional/constexpr/swap.cc: New test.
	* testsuite/20_util/optional/version.cc: New test.
2021-10-14 09:08:01 +01:00
Jonathan Wakely
881d1689a4 libstdc++: Implement std::move_only_function for C++23 (P0288R9)
libstdc++-v3/ChangeLog:

	* include/Makefile.am: Add new headers.
	* include/Makefile.in: Regenerate.
	* include/std/functional: Include <bits/move_only_function.h>.
	* include/std/version (__cpp_lib_move_only_function): Define.
	* include/bits/mofunc_impl.h: New file.
	* include/bits/move_only_function.h: New file.
	* testsuite/20_util/move_only_function/call.cc: New test.
	* testsuite/20_util/move_only_function/cons.cc: New test.
	* testsuite/20_util/move_only_function/move.cc: New test.
	* testsuite/20_util/move_only_function/version.cc: New test.
2021-10-06 20:12:01 +01:00
Jonathan Wakely
9e136807c5 libstdc++: Update __cpp_lib_adaptor_iterator_pair_constructor value
I started implementing this feature before it was voted into the C++ WP,
and forgot to update the feature test macro after it was approved.

This defines it to the correct value, as specified in the C++23 draft.

libstdc++-v3/ChangeLog:

	* include/bits/stl_queue.h
	(__cpp_lib_adaptor_iterator_pair_constructor): Set to correct
	value.
	* include/bits/stl_stack.h
	(__cpp_lib_adaptor_iterator_pair_constructor): Likewise.
	* include/std/version
	(__cpp_lib_adaptor_iterator_pair_constructor): Likewise.
	* testsuite/23_containers/queue/cons_from_iters.cc: Update
	expected value.
	* testsuite/23_containers/stack/cons_from_iters.cc: Likewise.
2021-10-05 09:35:46 +01:00
Jonathan Wakely
b7e8fb5e48 libstdc++: Add container adaptor constructors taking iterators (P1425R4)
This adds a feature that was recently added to the C++23 working draft.

Signed-off-by: Jonathan Wakely <jwakely@redhat.com>

libstdc++-v3/ChangeLog:

	* include/bits/stl_queue.h
	(__cpp_lib_adaptor_iterator_pair_constructor): Define for C++23, as
	per P1425R4.
	(queue(InputIterator, InputIterator)): Likewise.
	(queue(InputIterator, InputIterator, const Alloc&)): Likewise.
	* include/bits/stl_stack.h
	(__cpp_lib_adaptor_iterator_pair_constructor): Likewise.
	(stack(InputIterator, InputIterator)): Likewise.
	(stack(InputIterator, InputIterator, const Alloc&)): Likewise.
	* include/std/version (__cpp_lib_adaptor_iterator_pair_constructor):
	Define.
	* testsuite/23_containers/queue/cons_from_iters.cc: New test.
	* testsuite/23_containers/stack/cons_from_iters.cc: New test.
2021-10-01 20:36:55 +01:00
Jonathan Wakely
c46ecb0112 libstdc++: Allow visiting inherited variants [PR 90943]
Implement the changes from P2162R2 (as a DR for C++17).

Signed-off-by: Jonathan Wakely <jwakely@redhat.com>

libstdc++-v3/ChangeLog:

	PR libstdc++/90943
	* include/std/variant (__cpp_lib_variant): Update value.
	(__detail::__variant::__as): New helpers implementing the
	as-variant exposition-only function templates.
	(visit, visit<R>): Use __as to upcast the variant parameters.
	* include/std/version (__cpp_lib_variant): Update value.
	* testsuite/20_util/variant/visit_inherited.cc: New test.
2021-10-01 20:34:48 +01:00
Jason Merrill
76b75018b3 c++: implement C++17 hardware interference size
The last missing piece of the C++17 standard library is the hardware
intereference size constants.  Much of the delay in implementing these has
been due to uncertainty about what the right values are, and even whether
there is a single constant value that is suitable; the destructive
interference size is intended to be used in structure layout, so program
ABIs will depend on it.

In principle, both of these values should be the same as the target's L1
cache line size.  When compiling for a generic target that is intended to
support a range of target CPUs with different cache line sizes, the
constructive size should probably be the minimum size, and the destructive
size the maximum, unless you are constrained by ABI compatibility with
previous code.

From discussion on gcc-patches, I've come to the conclusion that the
solution to the difficulty of choosing stable values is to give up on it,
and instead encourage only uses where ABI stability is unimportant: in
particular, uses where the ABI is shared at most between translation units
built at the same time with the same flags.

To that end, I've added a warning for any use of the constant value of
std::hardware_destructive_interference_size in a header or module export.
Appropriate uses within a project can disable the warning.

A previous iteration of this patch included an -finterference-tune flag to
make the value vary with -mtune; this iteration makes that the default
behavior, which should be appropriate for all reasonable uses of the
variable.  The previous default of "stable-ish" seems to me likely to have
been more of an attractive nuisance; since we can't promise actual
stability, we should instead make proper uses more convenient.

JF Bastien's implementation proposal is summarized at
https://github.com/itanium-cxx-abi/cxx-abi/issues/74

I implement this by adding new --params for the two sizes.  Targets can
override these values in targetm.target_option.override() to support a range
of values for the generic target; otherwise, both will default to the L1
cache line size.

64 bytes still seems correct for all x86.

I'm not sure why he proposed 64/64 for generic 32-bit ARM, since the Cortex
A9 has a 32-byte cache line, so I'd think 32/64 would make more sense.

He proposed 64/128 for generic AArch64, but since the A64FX now has a 256B
cache line, I've changed that to 64/256.

Other arch maintainers are invited to set ranges for their generic targets
if that seems better than using the default cache line size for both values.

With the above choice to reject stability as a goal, getting these values
"right" is now just a matter of what we want the default optimization to be,
and we can feel free to adjust them as CPUs with different cache lines
become more and less common.

gcc/ChangeLog:

	* params.opt: Add destructive-interference-size and
	constructive-interference-size.
	* doc/invoke.texi: Document them.
	* config/aarch64/aarch64.c (aarch64_override_options_internal):
	Set them.
	* config/arm/arm.c (arm_option_override): Set them.
	* config/i386/i386-options.c (ix86_option_override_internal):
	Set them.

gcc/c-family/ChangeLog:

	* c.opt: Add -Winterference-size.
	* c-cppbuiltin.c (cpp_atomic_builtins): Add __GCC_DESTRUCTIVE_SIZE
	and __GCC_CONSTRUCTIVE_SIZE.

gcc/cp/ChangeLog:

	* constexpr.c (maybe_warn_about_constant_value):
	Complain about std::hardware_destructive_interference_size.
	(cxx_eval_constant_expression): Call it.
	* decl.c (cxx_init_decl_processing): Check
	--param *-interference-size values.

libstdc++-v3/ChangeLog:

	* include/std/version: Define __cpp_lib_hardware_interference_size.
	* libsupc++/new: Define hardware interference size variables.

gcc/testsuite/ChangeLog:

	* g++.dg/warn/Winterference.H: New file.
	* g++.dg/warn/Winterference.C: New test.
	* g++.target/aarch64/interference.C: New test.
	* g++.target/arm/interference.C: New test.
	* g++.target/i386/interference.C: New test.
2021-09-13 12:28:06 -04:00
Jonathan Wakely
5b73abd1a5 libstdc++: Define std::invoke_r for C++23 (P2136R3)
We already supported this feature as std::__invoke<R>, for internal use.
This just adds a public version of it to <functional>.

Internal uses should continue to include <bits/invoke.h> and use
std::__invoke<R> so that they don't need to include all of <functional>.

Signed-off-by: Jonathan Wakely <jwakely@redhat.com>

libstdc++-v3/ChangeLog:

	* include/std/functional (invoke_r): Define.
	* include/std/version (__cpp_lib_invoke_r): Define.
	* testsuite/20_util/function_objects/invoke/version.cc: Check
	for __cpp_lib_invoke_r as well as __cpp_lib_invoke.
	* testsuite/20_util/function_objects/invoke/4.cc: New test.
2021-09-02 17:48:45 +01:00
Jonathan Wakely
037ef219b2 libstdc++: Add std::is_layout_compatible trait for C++20
Signed-off-by: Jonathan Wakely <jwakely@redhat.com>

libstdc++-v3/ChangeLog:

	* include/std/type_traits (is_layout_compatible): Define.
	(is_corresponding_member): Define.
	* include/std/version (__cpp_lib_is_layout_compatible): Define.
	* testsuite/20_util/is_layout_compatible/is_corresponding_member.cc:
	New test.
	* testsuite/20_util/is_layout_compatible/value.cc: New test.
	* testsuite/20_util/is_layout_compatible/version.cc: New test.
	* testsuite/20_util/is_pointer_interconvertible/with_class.cc:
	New test.
	* testsuite/23_containers/span/layout_compat.cc: Do not use real
	std::is_layout_compatible trait if available.
2021-08-24 16:12:44 +01:00
Jonathan Wakely
4fa6c0ec35 libstdc++: Define std::is_pointer_interconvertible_base_of for C++20
Implement these traits using the new built-ins that Jakub added
recently.

Signed-off-by: Jonathan Wakely <jwakely@redhat.com>

libstdc++-v3/ChangeLog:

	* include/std/type_traits (__cpp_lib_is_pointer_interconvertible)
	(is_pointer_interconvertible_base_of_v)
	(is_pointer_interconvertible_base_of): Define for C++20.
	* include/std/version (__cpp_lib_is_pointer_interconvertible):
	Define.
	* testsuite/23_containers/span/layout_compat.cc: Use correct
	feature test macro for std::is_layout_compatible_v.
	* testsuite/20_util/is_pointer_interconvertible/value.cc: New test.
	* testsuite/20_util/is_pointer_interconvertible/version.cc: New test.
2021-08-11 16:53:22 +01:00
Jonathan Wakely
261d5a4a45 libstdc++: Reduce header dependencies on <array> and <utility>
This refactoring reduces the memory usage and compilation time to parse
a number of headers that depend on std::pair, std::tuple or std::array.
Previously the headers for these class templates were all intertwined,
due to the common dependency on std::tuple_size, std::tuple_element and
their std::get overloads. This decouples the headers by moving some
parts of <utility> into a new <bits/utility.h> header. This means that
<array> and <tuple> no longer need to include the whole of <utility>,
and <tuple> no longer needs to include <array>.

This decoupling benefits headers such as <thread> and <scoped_allocator>
which only need std::tuple, and so no longer have to parse std::array.

Some other headers such as <any>, <optional> and <variant> no longer
need to include <utility> just for the std::in_place tag types, so
do not have to parse the std::pair definitions.

Removing direct uses of <utility> also means that the std::rel_ops
namespace is not transitively declared by other headers.

Signed-off-by: Jonathan Wakely <jwakely@redhat.com>

libstdc++-v3/ChangeLog:

	* include/Makefile.am: Add bits/utility.h header.
	* include/Makefile.in: Regenerate.
	* include/bits/utility.h: New file.
	* include/std/utility (tuple_size, tuple_element): Move
	to new header.
	* include/std/type_traits (__is_tuple_like_impl<tuple<T...>>):
	Move to <tuple>.
	(_Index_tuple, _Build_index_tuple, integer_sequence): Likewise.
	(in_place_t, in_place_index_t, in_place_type_t): Likewise.
	* include/bits/ranges_util.h: Include new header instead of
	<utility>.
	* include/bits/stl_pair.h (tuple_size, tuple_element): Move
	partial specializations for std::pair here.
	(get): Move overloads for std::pair here.
	* include/std/any: Include new header instead of <utility>.
	* include/std/array: Likewise.
	* include/std/memory_resource: Likewise.
	* include/std/optional: Likewise.
	* include/std/variant: Likewise.
	* include/std/tuple: Likewise.
	(__is_tuple_like_impl<tuple<T...>>): Move here.
	(get) Declare overloads for std::array.
	* include/std/version (__cpp_lib_tuples_by_type): Change type
	to long.
	* testsuite/20_util/optional/84601.cc: Include <utility>.
	* testsuite/20_util/specialized_algorithms/uninitialized_fill/constrained.cc:
	Likewise.
	* testsuite/23_containers/array/tuple_interface/get_neg.cc:
	Adjust dg-error line numbers.
	* testsuite/std/ranges/access/cbegin.cc: Include <utility>.
	* testsuite/std/ranges/access/cend.cc: Likewise.
	* testsuite/std/ranges/access/end.cc: Likewise.
	* testsuite/std/ranges/single_view.cc: Likewise.
2021-07-27 12:04:18 +01:00
Patrick Palka
4b4f5666b4 libstdc++: Implement P2325 changes to default-constructibility of views
This implements the wording changes of P2325R3 "Views should not be
required to be default constructible".  Changes are relatively
straightforward, besides perhaps those to __box (which now stands
for copyable-box instead of semiregular-box) and __non_propagating_cache.

For __box, this patch implements the recommended practice to also avoid
std::optional when the boxed type is nothrow_move/copy_constructible.

For __non_propagating_cache, now that it's used by split_view::_M_current,
we need to add assignment from a value of the underlying type to the
subset of the std::optional API implemented for the cache (needed by
split_view::begin()).  Hence the new __non_propagating_cache::operator=
overload.

In passing, this fixes the undesirable list-init in the constructors of
the partial specialization of __box as reported in PR100475 comment #7.

libstdc++-v3/ChangeLog:

	* include/bits/iterator_concepts.h (weakly_incrementable): Remove
	default_initializable requirement.
	* include/bits/ranges_base.h (ranges::view): Likewise.
	* include/bits/ranges_util.h (subrange): Constrain the default
	ctor.
	* include/bits/stl_iterator.h (back_insert_iterator): Remove the
	default ctor.
	(front_insert_iterator): Likewise.
	(insert_iterator): Likewise.  Remove NSDMIs.
	(common_iterator): Constrain the default ctor.
	(counted_iterator): Likewise.
	* include/bits/stream_iterator.h (ostream_iterator): Remove the
	default ctor.
	* include/std/ranges (__detail::__box::operator=): Handle
	self-assignment in the primary template.
	(__detail::__box): In the partial specialization: adjust
	constraints as per P2325.  Add specialized operator= for the
	case when the wrapped type is not copyable.  Constrain the
	default ctor.  Avoid list-initialization.
	(single_view): Constraint the default ctor.
	(iota_view): Relax semiregular constraint to copyable.
	Constrain the default ctor.
	(iota_view::_Iterator): Constraint the default ctor.
	(basic_istream_view): Remove the default ctor.  Remove NSDMIs.
	Remove redundant checks for empty _M_stream.
	(basic_istream_view::_Iterator): Likewise.
	(ref_view): Remove the default ctor.  Remove NSDMIs.
	(ref_view::_Iterator): Constrain the default ctor.
	(__detail::__non_propagating_cache::operator=): Define overload
	for assigning from a value of the underlying type.
	(filter_view): Likewise.
	(filter_view::_Iterator): Likewise.
	(transform_view): Likewise.
	(transform_view::_Iterator): Likewise.
	(take_view): Likewise.
	(take_view::_Iterator): Likewise.
	(take_while_view): Likewise.
	(take_while_view::_Iterator): Likewise.
	(drop_while_view): Likewise.
	(drop_while_view::_Iterator): Likewise.
	(join_view): Likewise.
	(split_view::_OuterIter::__current): Adjust after changing the
	type of _M_current.
	(split_view::_M_current): Wrap it in a __non_propagating_cache.
	(split_view::split_view): Constrain the default ctor.
	(common_view): Constrain the default ctor.
	(reverse_view): Likewise.
	(elements_view): Likewise.
	* include/std/span (enable_view<span<_ElementType, _Extent>>):
	Define this partial specialization to true unconditionally.
	* include/std/version (__cpp_lib_ranges): Adjust value.
	* testsuite/24_iterators/back_insert_iterator/constexpr.cc:
	Don't attempt to default construct a back_insert_iterator.
	* testsuite/24_iterators/front_insert_iterator/constexpr.cc:
	Don't attempt to default construct a front_insert_iterator.
	* testsuite/24_iterators/insert_iterator/constexpr.cc:
	Don't attempt to default construct an insert_iterator.
	* testsuite/24_iterators/ostream_iterator/requirements/constexpr.cc:
	Remove this test for default constructibility of ostream_iterator.
	* testsuite/std/ranges/97600.cc: Don't attempt to default
	construct a basic_istream_view.
	* testsuite/std/ranges/adaptors/detail/semiregular_box.cc:
	Rename to ...
	* testsuite/std/ranges/adaptors/detail/copyable_box.cc: ... this.
	(test02): Adjust now that __box is copyable-box not
	semiregular-box.
	(test03): New test.
	* testsuite/std/ranges/p2325.cc: New test.
	* testsuite/std/ranges/single_view.cc (test06): New test.
	* testsuite/std/ranges/view.cc: Adjust now that view doesn't
	require default_initializable.
2021-06-17 22:29:03 -04:00
Jonathan Wakely
b376b1ef38 libstdc++: Simplify constexpr checks in std::char_traits [PR 91488]
This removes the helper functions added by r8-1294 to detect whether the
char_traits member functions can be evaluated at compile time. Instead,
we can just use __builtin_constant_evaluated directly, which is well
supported by non-GCC compilers by now.

As a result, there is a chance that those members will no longer be
usable in constant expressions when using old versions of non-GCC
compilers. Make the relevant feature test macros depend on the
availability of __builtin_constant_evaluated, so they are defined only
when the feature is actualyl available.

The new testcase from the PR is added to the libitm testsuite, because
that's where we can be sure it's OK to use the -fgnu-tm option.

Signed-off-by: Jonathan Wakely <jwakely@redhat.com>

	PR libstdc++/91488

libstdc++-v3/ChangeLog:

	* include/bits/basic_string.h (__cpp_lib_constexpr_string): Only
	define when is_constant_evaluated is available.
	* include/bits/char_traits.h (__cpp_lib_constexpr_char_traits):
	Likewise.
	(__constant_string_p, __constant_array_p): Remove.
	(char_traits): Use is_constant_evaluated directly.
	* include/std/version (__cpp_lib_constexpr_char_traits)
	(__cpp_lib_constexpr_string): Only define when
	is_constant_evaluated is available.

libitm/ChangeLog:

	* testsuite/libitm.c++/libstdc++-pr91488.C: New test.
2021-06-17 22:00:58 +01:00
Jonathan Wakely
f78f25f438 libstdc++: Add feature test macro for heterogeneous lookup in unordered containers
Also update the C++20 status docs.

Signed-off-by: Jonathan Wakely <jwakely@redhat.com>

libstdc++-v3/ChangeLog:

	* doc/xml/manual/status_cxx2020.xml:
	* doc/html/*: Regenerate.
	* include/bits/hashtable.h (__cpp_lib_generic_unordered_lookup):
	Define.
	* include/std/version (__cpp_lib_generic_unordered_lookup):
	Define.
	* testsuite/23_containers/unordered_map/operations/1.cc: Check
	feature test macro.
	* testsuite/23_containers/unordered_set/operations/1.cc:
	Likewise.
2021-06-04 15:59:37 +01:00
Jonathan Wakely
3215d4f5b3 libstdc++: Fix inconsistent feature test macros
The __cpp_lib_constexpr_string and __cpp_lib_semaphore feature test
macros are not defined consistently in <version> and the relevant header
for the feature.

libstdc++-v3/ChangeLog:

	* include/bits/basic_string.h (__cpp_lib_constexpr_string):
	Only define for C++17 and later.
	* include/std/version (__cpp_lib_semaphore): Fix condition
	to match the one in <semaphore>.
2021-04-30 21:58:45 +01:00
Jonathan Wakely
3da80ed7ef libstdc++: Define __cpp_lib_constexpr_string macro
As noted in r11-1339-gb6ab9ecd550227684643b41e9e33a4d3466724d8 we define
a non-standard __cpp_lib_constexpr_char_traits feature test macro to
indicate support for P0426R1 and P1032R1. At some point last year the
__cpp_lib_constexpr_string macro was retconned to indicate support for
those papers. This adds the new macro (which we didn't previously
define, because it referred to P0980R1 "Making std::string constexpr"
which we don't support).

libstdc++-v3/ChangeLog:

	* include/bits/basic_string.h (__cpp_lib_constexpr_string): Define.
	* include/std/version (__cpp_lib_constexpr_string): Define.
	* testsuite/21_strings/char_traits/requirements/constexpr_functions_c++17.cc:
	Check for __cpp_lib_constexpr_string.
	* testsuite/21_strings/char_traits/requirements/constexpr_functions_c++20.cc:
	Likewise.
	* testsuite/21_strings/char_traits/requirements/version.cc: New test.
2021-04-28 15:56:04 +01:00
Jonathan Wakely
f1a68574b1 libstdc++: Define __cpp_lib_to_chars for C++20 [PR 100146]
This defines the feature test macro when uselocale is available, because
the floating-point std::from_chars support currently depends on that.

Co-authored-by: Jakub Jelinek <jakub@redhat.com>

libstdc++-v3/ChangeLog:

	PR libstdc++/100146
	* include/std/charconv (__cpp_lib_to_chars): Define
	conditionally.
	* include/std/version (__cpp_lib_to_chars): Likewise..
	* testsuite/20_util/from_chars/4.cc: Only check feature test
	macro, not _GLIBCXX_HAVE_USELOCALE.
	* testsuite/20_util/from_chars/5.cc: Likewise.
	* testsuite/20_util/from_chars/6.cc: Likewise.
	* testsuite/20_util/to_chars/long_double.cc: Likewise.
2021-04-20 12:50:50 +01:00
Jonathan Wakely
b8ecdc7727 libstdc++: Add std::is_scoped_enum for C++23
Implement this C++23 feature, as proposed by P1048R1.

This implementation assumes that a C++23 compiler supports concepts
already. I don't see any point in using preprocessor hacks to detect
compilers which define __cplusplus to a post-C++20 value but don't
support concepts yet.

libstdc++-v3/ChangeLog:

	* include/std/type_traits (is_scoped_enum): Define.
	* include/std/version (__cpp_lib_is_scoped_enum): Define.
	* testsuite/20_util/is_scoped_enum/value.cc: New test.
	* testsuite/20_util/is_scoped_enum/version.cc: New test.
2021-03-19 20:10:56 +00:00
Jonathan Wakely
7244879b88 libstdc++: Add std::to_underlying for C++23
Implement P1682R2 as just approved for C++23.

libstdc++-v3/ChangeLog:

	* include/std/utility (to_underlying): Define.
	* include/std/version (__cpp_lib_to_underlying): Define.
	* testsuite/20_util/to_underlying/1.cc: New test.
	* testsuite/20_util/to_underlying/version.cc: New test.
2021-02-25 11:53:58 +00:00
Paul Fee
f004d6d9fa libstdc++: Add string contains member functions for C++2b
This implements WG21 P1679R3, adding contains member functions to
basic_string_view and basic_string.

libstdc++-v3/ChangeLog:

	* include/bits/basic_string.h (basic_string::contains): New
	member functions.
	* include/std/string_view (basic_string_view::contains):
	Likewise.
	* include/std/version (__cpp_lib_string_contains): Define.
	* testsuite/21_strings/basic_string/operations/starts_with/char/1.cc:
	Remove trailing whitespace.
	* testsuite/21_strings/basic_string/operations/starts_with/wchar_t/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string/operations/contains/char/1.cc: New test.
	* testsuite/21_strings/basic_string/operations/contains/wchar_t/1.cc: New test.
	* testsuite/21_strings/basic_string_view/operations/contains/char/1.cc: New test.
	* testsuite/21_strings/basic_string_view/operations/contains/char/2.cc: New test.
	* testsuite/21_strings/basic_string_view/operations/contains/wchar_t/1.cc: New test.
2021-01-27 12:37:36 +00:00
Jonathan Wakely
194a9d67be libstdc++: Update copyright dates on new files
The patch adding these files was approved in 2020 but it wasn't
committed until 2021, so the copyright years were not updated along with
the years in all the existing files.

libstdc++-v3/ChangeLog:

	* include/std/barrier: Update copyright years. Fix whitespace.
	* include/std/version: Fix whitespace.
	* testsuite/30_threads/barrier/1.cc: Update copyright years.
	* testsuite/30_threads/barrier/2.cc: Likewise.
	* testsuite/30_threads/barrier/arrive.cc: Likewise.
	* testsuite/30_threads/barrier/arrive_and_drop.cc: Likewise.
	* testsuite/30_threads/barrier/arrive_and_wait.cc: Likewise.
	* testsuite/30_threads/barrier/completion.cc: Likewise.
2021-01-14 14:25:10 +00:00
Thomas Rodgers
b7c3f201be libstdc++: Add support for C++20 barriers
Adds <barrier>

libstdc++-v3/ChangeLog:

	* doc/doxygen/user.cfg.in: Add new header.
	* include/Makefile.am (std_headers): likewise.
	* include/Makefile.in: Regenerate.
	* include/precompiled/stdc++.h: Add new header.
	* include/std/barrier: New file.
	* include/std/version: Add __cpp_lib_barrier feature test macro.
	* testsuite/30_threads/barrier/1.cc: New test.
	* testsuite/30_threads/barrier/2.cc: Likewise.
	* testsuite/30_threads/barrier/arrive_and_drop.cc: Likewise.
	* testsuite/30_threads/barrier/arrive_and_wait.cc: Likewise.
	* testsuite/30_threads/barrier/arrive.cc: Likewise.
	* testsuite/30_threads/barrier/completion.cc: Likewise.
2021-01-07 12:52:37 -08:00
Jakub Jelinek
99dee82307 Update copyright years. 2021-01-04 10:26:59 +01:00
JeanHeyd Meneide
57d76ee9cf libtdc++: Define std::source_location for C++20
This doesn't define a new _GLIBCXX_HAVE_BUILTIN_SOURCE_LOCATION macro.
because using __has_builtin(__builtin_source_location) is sufficient.
Currently only GCC supports it, but if/when Clang and Intel add it the
__has_builtin check should for them too.

Co-authored-by: Jonathan Wakely <jwakely@redhat.com>

libstdc++-v3/ChangeLog:

	* doc/doxygen/user.cfg.in (INPUT): Add <source_location>.
	* include/Makefile.am: Add <source_location>.
	* include/Makefile.in: Regenerate.
	* include/std/version (__cpp_lib_source_location): Define.
	* include/std/source_location: New file.
	* testsuite/18_support/source_location/1.cc: New test.
	* testsuite/18_support/source_location/consteval.cc: New test.
	* testsuite/18_support/source_location/srcloc.h: New test.
	* testsuite/18_support/source_location/version.cc: New test.
2020-12-03 19:17:13 +00:00
Jonathan Wakely
9e433b3461 libstdc++: Add std::bit_cast for C++20 [PR 93121]
Thanks to Jakub's addition of the built-in, we can add this to the
library now. The compiler tests for the built-in are quite extensive,
including verifying the constraints, so this only adds minimal tests to
the library testsuite.

This doesn't add a new _GLIBCXX_HAVE_BUILTIN_BIT_CAST because using
__has_builtin(__builtin_bit_cast) works for GCC and versions of Clang
that provide the built-in.

libstdc++-v3/ChangeLog:

	PR libstdc++/93121
	* include/std/bit (__cpp_lib_bit_cast, bit_cast): Define.
	* include/std/version (__cpp_lib_bit_cast): Define.
	* testsuite/26_numerics/bit/bit.cast/bit_cast.cc: New test.
	* testsuite/26_numerics/bit/bit.cast/version.cc: New test.
2020-12-03 19:17:13 +00:00
Jonathan Wakely
670f5095e4 libstdc++: Make preprocessor checks for __cpp_lib_atomic_wait consistent
This changes some #ifdef checks to use #if instead.

libstdc++-v3/ChangeLog:

	* include/bits/atomic_timed_wait.h: Use #if instead of #ifdef.
	* include/bits/semaphore_base.h: Likewise.
	* include/std/version: Remove trailing whitespace.
2020-12-02 00:39:22 +00:00
Thomas Rodgers
6591e42269 Add feature test macro for atomic<T>::wait
Adds __cpp_lib_atomic_wait feature test macro which was overlooked in
the initial commit of this feature. Replaces uses of
_GLIBCXX_HAVE_ATOMIC_WAIT.

libstdc++-v3/ChangeLog:

	* include/bits/atomic_base.h: Replace usage of
	_GLIBCXX_HAVE_ATOMIC_WAIT with __cpp_lib_atomic_wait.
	* include/bits/atomic_timed_wait.h: Likewise.
	* include/bits/atomic_wait.h: Define __cpp_lib_atomic_wait
	feature test macro.
	* include/bits/semaphore_base.h: Replace usage of
	_GLIBCXX_HAVE_ATOMIC_WAIT with __cpp_lib_atomic_wait.
	* include/std/atomic: Likewise.
	* include/std/latch: Likewise.
	* include/std/semaphore: Likewise.
	* include/std/version: Define __cpp_lib_atomic wait
	feature test macro and replace usage of
	_GLIBCXX_HAVE_ATOMIC_WAIT.
	* testsuite/29_atomics/atomic/wait_notify/1.cc: New test.
	* testsuite/29_atomics/atomic/wait_notify/2.cc: Likewise.
2020-12-01 15:43:17 -08:00
Jonathan Wakely
7198827486 libstdc++: Only define std::latch if atomic waiting is available
libstdc++-v3/ChangeLog:

	* include/std/latch: Depend on _GLIBCXX_HAS_GTHREADS and
	_GLIBCXX_HAVE_LINUX_FUTEX.
	* include/std/version (__cpp_lib_latch): Define conditionally.
2020-11-26 22:36:44 +00:00
Jonathan Wakely
183ae52b22 libstdc++: make atomic waiting depend on gthreads or futexes
libstdc++-v3/ChangeLog:

	* include/bits/atomic_wait.h: Do not define anything unless
	gthreads or futexes are available.
	* include/bits/atomic_timed_wait.h: Likewise.
	* include/bits/semaphore_base.h: Likewise.
	* include/std/semaphore: Likewise.
	* include/bits/atomic_base.h (atomic_flag::wait)
	(atomic_flag::notify_one, atomic_flag::notify_all)
	(__atomic_base<I>::wait, __atomic_base<I>::notify_one)
	(__atomic_base<I>::notify_all, __atomic_base<P*>::wait)
	(__atomic_base<P*>::notify_one, __atomic_base<P*>::notify_all)
	(__atomic_impl::wait, __atomic_impl::notify_one)
	(__atomic_impl::notify_all, __atomic_float::wait)
	(__atomic_float::notify_one, __atomic_float::notify_all)
	(__atomic_ref::wait, __atomic_ref::notify_one)
	(__atomic_ref::notify_all): Only define if gthreads or futexes
	are available.
	* include/std/atomic (atomic::wait, atomic::notify_one)
	(atomic::notify_all): Likewise.
	* include/std/version (__cpp_lib_semaphore): Define
	conditionally.
2020-11-23 18:12:39 +00:00
Thomas Rodgers
83a1beee27 libstdc++: Add C++2a synchronization support
Add support for -
  * atomic_flag::wait/notify_one/notify_all
  * atomic::wait/notify_one/notify_all
  * counting_semaphore
  * binary_semaphore
  * latch

libstdc++-v3/ChangeLog:

	* include/Makefile.am (bits_headers): Add new header.
	* include/Makefile.in: Regenerate.
	* include/bits/atomic_base.h (__atomic_flag::wait): Define.
	(__atomic_flag::notify_one): Likewise.
	(__atomic_flag::notify_all): Likewise.
	(__atomic_base<_Itp>::wait): Likewise.
	(__atomic_base<_Itp>::notify_one): Likewise.
	(__atomic_base<_Itp>::notify_all): Likewise.
	(__atomic_base<_Ptp*>::wait): Likewise.
	(__atomic_base<_Ptp*>::notify_one): Likewise.
	(__atomic_base<_Ptp*>::notify_all): Likewise.
	(__atomic_impl::wait): Likewise.
	(__atomic_impl::notify_one): Likewise.
	(__atomic_impl::notify_all): Likewise.
	(__atomic_float<_Fp>::wait): Likewise.
	(__atomic_float<_Fp>::notify_one): Likewise.
	(__atomic_float<_Fp>::notify_all): Likewise.
	(__atomic_ref<_Tp>::wait): Likewise.
	(__atomic_ref<_Tp>::notify_one): Likewise.
	(__atomic_ref<_Tp>::notify_all): Likewise.
	(atomic_wait<_Tp>): Likewise.
	(atomic_wait_explicit<_Tp>): Likewise.
	(atomic_notify_one<_Tp>): Likewise.
	(atomic_notify_all<_Tp>): Likewise.
	* include/bits/atomic_wait.h: New file.
	* include/bits/atomic_timed_wait.h: New file.
	* include/bits/semaphore_base.h: New file.
	* include/std/atomic (atomic<bool>::wait): Define.
	(atomic<bool>::wait_one): Likewise.
	(atomic<bool>::wait_all): Likewise.
	(atomic<_Tp>::wait): Likewise.
	(atomic<_Tp>::wait_one): Likewise.
	(atomic<_Tp>::wait_all): Likewise.
	(atomic<_Tp*>::wait): Likewise.
	(atomic<_Tp*>::wait_one): Likewise.
	(atomic<_Tp*>::wait_all): Likewise.
	* include/std/latch: New file.
	* include/std/semaphore: New file.
	* include/std/version: Add __cpp_lib_semaphore and
	__cpp_lib_latch defines.
	* testsuite/29_atomics/atomic/wait_notify/bool.cc: New test.
	* testsuite/29_atomics/atomic/wait_notify/pointers.cc: Likewise.
	* testsuite/29_atomics/atomic/wait_notify/generic.cc: Liekwise.
	* testsuite/29_atomics/atomic_flag/wait_notify/1.cc: Likewise.
	* testsuite/29_atomics/atomic_float/wait_notify.cc: Likewise.
	* testsuite/29_atomics/atomic_integral/wait_notify.cc: Likewise.
	* testsuite/29_atomics/atomic_ref/wait_notify.cc: Likewise.
	* testsuite/30_threads/semaphore/1.cc: New test.
	* testsuite/30_threads/semaphore/2.cc: Likewise.
	* testsuite/30_threads/semaphore/least_max_value_neg.cc: Likewise.
	* testsuite/30_threads/semaphore/try_acquire.cc: Likewise.
	* testsuite/30_threads/semaphore/try_acquire_for.cc: Likewise.
	* testsuite/30_threads/semaphore/try_acquire_posix.cc: Likewise.
	* testsuite/30_threads/semaphore/try_acquire_until.cc: Likewise.
	* testsuite/30_threads/latch/1.cc: New test.
	* testsuite/30_threads/latch/2.cc: New test.
	* testsuite/30_threads/latch/3.cc: New test.
	* testsuite/util/atomic/wait_notify_util.h: New File.
2020-11-20 14:40:18 -08:00
Jonathan Wakely
ecf65330c1 libstdc++: Fix unconditional definition of __cpp_lib_span in <version> [PR 97869}
The <span> header is empty unless Concepts are supported, but <version>
defines the __cpp_lib_span feature test macro unconditionally. It should
be guarded by the same conditions as in <span>.

libstdc++-v3/ChangeLog:

	PR libstdc++/97869
	* include/precompiled/stdc++.h: Include <coroutine>.
	* include/std/version (__cpp_lib_span): Check __cpp_lib_concepts
	before defining.
2020-11-17 16:13:14 +00:00
Thomas Rodgers
6bcbcea058 libstdc++: Add c++2a <syncstream>
libstdc++-v3/ChangeLog:
	* doc/doxygen/user.cfg.in (INPUT): Add new header.
	* include/Makefile.am (std_headers): Add new header.
	* include/Makefile.in: Regenerate.
	* include/precompiled/stdc++.h: Include new header.
	* include/std/syncstream: New header.
	* include/std/version: Add __cpp_lib_syncbuf.
	* testsuite/27_io/basic_syncbuf/1.cc: New test.
	* testsuite/27_io/basic_syncbuf/2.cc: Likewise.
	* testsuite/27_io/basic_syncbuf/basic_ops/1.cc:
	Likewise.
	* testsuite/27_io/basic_syncbuf/requirements/types.cc:
	Likewise.
	* testsuite/27_io/basic_syncbuf/sync_ops/1.cc:
	Likewise.
	* testsuite/27_io/basic_syncstream/1.cc: Likewise.
	* testsuite/27_io/basic_syncstream/2.cc: Likewise.
	* testsuite/27_io/basic_syncstream/basic_ops/1.cc:
	Likewise.
	* testsuite/27_io/basic_syncstream/requirements/types.cc:
	Likewise.
2020-11-02 10:41:32 -08:00
Jonathan Wakely
f5d9bc8ae8 libstdc++: Only include <condition_variable> in <shared_mutex> if needed
The <condition_variable> header is not small, so <shared_mutex> should
not include it unless it actually needs std::condition_variable, which
is only the case when we don't have pthread_rwlock_t and the POSIX
Timers option.

The <shared_mutex> header would be even smaller if we had a header for
std::condition_variable (separate from std::condition_variable_any).
That's already planned for a future change.

And <memory_resource> would be even smaller if it was possible to get
std::shared_mutex without std::shared_timed_mutex (which depends on
<chrono>). For that to be effective, the synchronized_pool_resource
would have to create its own simpler version of std::shared_lock without
the timed waiting functions. I have no plans to do that.

libstdc++-v3/ChangeLog:

	* include/std/shared_mutex: Only include <condition_variable>
	when pthread_rwlock_t and POSIX timers are not available.
	(__cpp_lib_shared_mutex, __cpp_lib_shared_timed_mutex): Change
	value to be type 'long'.
	* include/std/version (__cpp_lib_shared_mutex)
	(__cpp_lib_shared_timed_mutex): Likewise.
2020-10-22 18:49:38 +01:00
Jonathan Wakely
b1e7c6fce1 libstdc++: Reduce header dependencies in and on <memory>
By moving std::make_obj_using_allocator and the related "utility
functions for uses-allocator construction" to a new header, we can avoid
including the whole of <memory> in <scoped_allocator> and
<memory_resource>.

In order to simplify the implementation of those utility functions they
now use concepts unconditionally. They are no longer defined if
__cpp_concepts is not defined. To simplify the code that uses those
functions I've introduced a __cpp_lib_make_obj_using_allocator feature
test macro (not specified in the standard, which might be an oversight).
That allows the code in <memory_resource> and <scoped_allocator> to
check the feature test macro to decide whether to use the new utilities,
or fall back to the C++17 code.

At the same time, this reshuffles some of the headers included by
<memory> so that they are (mostly?) self-contained. It should no longer
be necessary to include other headers before <bits/shared_ptr.h> when
other parts of the library want to use std::shared_ptr without including
the whole of <memory>.

libstdc++-v3/ChangeLog:

	* include/Makefile.am: Add new header.
	* include/Makefile.in: Regenerate.
	* include/bits/shared_ptr.h: Include <iosfwd>.
	* include/bits/shared_ptr_base.h: Include required headers here
	directly, instead of in <memory>.
	* include/bits/uses_allocator_args.h: New file. Move utility
	functions for uses-allocator construction from <memory> to here.
	Only define the utility functions when concepts are available.
	(__cpp_lib_make_obj_using_allocator): Define non-standard
	feature test macro.
	* include/std/condition_variable: Remove unused headers.
	* include/std/future: Likewise.
	* include/std/memory: Remove headers that are not needed
	directly, and are now inclkuded where they're needed. Include
	new <bits/uses_allocator_args.h> header.
	* include/std/memory_resource: Include only the necessary
	headers. Use new feature test macro to detect support for the
	utility functions.
	* include/std/scoped_allocator: Likewise.
	* include/std/version (__cpp_lib_make_obj_using_allocator):
	Define.
2020-10-22 18:42:03 +01:00
Jonathan Wakely
f903c13ce8 libstdc++: Fix macro redefinition warnings
Including <version> after <iterator> gives a warning about redefining
the __cpp_lib_array_constexpr macro. What happens is that <iterator>
sets the C++20 value, then <version> redefines it to the C++17 value,
then undefines it and defines it again to the C++20 value.

This change avoids defining it to the C++17 value when compiling C++20
or later (which also means we no longer need the #undef).

A similar warning happens for __cpp_lib_constexpr_char_traits when
including <version> after any header that includes <bits/char_traits.h>.

libstdc++-v3/ChangeLog:

	* include/std/version (__cpp_lib_array_constexpr):
	(__cpp_lib_constexpr_char_traits): Only define C++17 value when
	compiling C++17.
2020-09-10 18:51:24 +01:00
Jonathan Wakely
b6ab9ecd55 libstdc++: Update value of __cpp_lib_constexpr_char_traits for C++20
Although not required by SD-6 or the C++20 draft, we define the macro
__cpp_lib_constexpr_char_traits to indicate support for P0432R1. This
updates the value in C++20 mode for the P1032R1 changes to char_traits.

	* include/bits/char_traits.h (__cpp_lib_constexpr_char_traits):
	Update value for C++20.
	* include/std/version (__cpp_lib_constexpr_char_traits): Likewise.
	* testsuite/21_strings/char_traits/requirements/constexpr_functions_c++17.cc:
	Update expected value.
	* testsuite/21_strings/char_traits/requirements/constexpr_functions_c++20.cc:
	Likewise.
2020-06-15 14:31:26 +01:00
Ulrich Drepper
491ba663e0 Implent C++20 std::atomic_flag::test
* include/bits/atomic_base.h (atomic_flag): Implement test member
        function.
        * include/std/version: Define __cpp_lib_atomic_flag_test.
        * testsuite/29_atomics/atomic_flag/test/explicit.cc: New file.
        * testsuite/29_atomics/atomic_flag/test/implicit.cc: New file.
2020-05-12 07:37:09 +02:00
Jonathan Wakely
d0330a0360 libstdc++: Fixes for feature test macros (PR 91480)
Remove the non-standard __cpp_lib_allocator_is_always_equal macro and
add the missing macros for P1032R1.

	PR libstdc++/91480
	* include/bits/allocator.h (__cpp_lib_allocator_is_always_equal):
	Remove non-standard macro.
	* include/bits/stl_iterator.h (__cpp_lib_constexpr_iterator): Define
	to indicate P1032R1 support.
	* include/bits/stl_pair.h (__cpp_lib_constexpr_utility): Likewise.
	* include/std/string_view (__cpp_lib_constexpr_string_view): Likewise.
	* include/std/tuple (__cpp_lib_constexpr_tuple): Likewise.
	* include/std/version (__cpp_lib_allocator_is_always_equal): Remove.
	(__cpp_lib_constexpr_iterator, __cpp_lib_constexpr_string_view)
	(__cpp_lib_constexpr_tuple, __cpp_lib_constexpr_utility): Define.
	* testsuite/20_util/function_objects/constexpr_searcher.cc: Check
	feature test macro.
	* testsuite/20_util/tuple/cons/constexpr_allocator_arg_t.cc: Likewise.
	* testsuite/21_strings/basic_string_view/operations/copy/char/
	constexpr.cc: Likewise.
	* testsuite/24_iterators/insert_iterator/constexpr.cc: Likewise.
2020-04-28 23:40:18 +01:00
Jonathan Wakely
40541efe1c libstdc++: Change __cpp_lib_array_constexpr for C++17 again
This partially reverts my previous change related to this macro. The
C++20 constexpr iterator requirements are always met by array:iterator,
because it's just a pointer. So the macro can be set to 201803 even in
C++17 mode.

	* include/bits/stl_iterator.h (__cpp_lib_array_constexpr): Revert
	value for C++17 to 201803L because P0858R0 is supported for C++17.
	* include/std/version (__cpp_lib_array_constexpr): Likewise.
	* testsuite/23_containers/array/element_access/constexpr_c++17.cc:
	Check for value corresponding to P0031R0 features being tested.
	* testsuite/23_containers/array/requirements/constexpr_iter.cc:
	Check for value corresponding to P0858R0 features being tested.
2020-04-23 21:39:33 +01:00
Jonathan Wakely
a2dcb56c94 libstdc++: Define __cpp_lib_three_way_comparison for freestanding
The <compare> header is always supported, not only for hosted configs.

	* include/std/version (__cpp_lib_three_way_comparison): Define for
	freestanding builds.
2020-04-23 21:39:33 +01:00
Iain Sandoe
dcf69ac544 coroutines, libstdc++-v3: Update to n4861 C++20 DIS.
Update the inline namespace to __n4861.
Add '__cpp_lib_coroutine' defined to 201902L per n4861.

libstdc++-v3/ChangeLog:

2020-04-23  Iain Sandoe  <iain@sandoe.co.uk>

	* include/std/coroutine: Update the inline namespace to __n4861.
	Add the __cpp_lib_coroutine define, set to 201902L.
	* include/std/version: Add __cpp_lib_coroutine, set to 201902L.

gcc/testsuite/ChangeLog:

2020-04-23  Iain Sandoe  <iain@sandoe.co.uk>

	* g++.dg/coroutines/coro-bad-alloc-00-bad-op-new.C: Adjust for
	changed inline namespace.
	* g++.dg/coroutines/coro-bad-alloc-01-bad-op-del.C: Likewise.
	* g++.dg/coroutines/coro-bad-alloc-02-no-op-new-nt.C: Likewise
	* g++.dg/coroutines/coro.h: Likewise
2020-04-23 16:27:29 +01:00
Jonathan Wakely
aac39307e8 libstdc++: Define __cpp_lib_execution feature test macro
This macro has never been defined by libstdc++, despite supporting the
parallel algorithms. It should have a different value for C++17 and
C++20, because P1001R2 should not be supported in C++17, but
unsequenced_policy is defined for C++17 (see PR p4702).

	* include/std/execution (__cpp_lib_execution): Define to indicate
	support for P0024R2 and P1001R2.
	* include/std/version (__cpp_lib_execution): Define.
	* testsuite/25_algorithms/pstl/feature_test.cc: Only test macro
	defined by <algorithm>, move other tests to new tests ...
	* testsuite/25_algorithms/pstl/feature_test-2.cc: New test.
	* testsuite/25_algorithms/pstl/feature_test-3.cc: New test.
	* testsuite/25_algorithms/pstl/feature_test-4.cc: New test.
	* testsuite/25_algorithms/pstl/feature_test-5.cc: New test.
2020-04-22 22:54:35 +01:00
Jonathan Wakely
e851aa1703 libstdc++: Update (and revert) value of __cpp_lib_array_constexpr
This macro should have been updated to 201811 when the last C++20
changes were implemented. However those changes are not enabled for
C++17 mode, so the macro should only have the new value in C++20 mode.

This change ensures that the macro is defined to 201603 for C++17 and
201811 for C++20.

	* include/bits/stl_iterator.h (__cpp_lib_array_constexpr): Define
	different values for C++17 and C++20, to indicate different feature
	sets. Update value for C++20 to indicate P1032R1 support.
	* include/std/version (__cpp_lib_array_constexpr): Likewise.
	* testsuite/23_containers/array/comparison_operators/constexpr.cc:
	Check feature test macro.
	* testsuite/23_containers/array/element_access/constexpr_c++17.cc:
	New test.
	* testsuite/23_containers/array/requirements/constexpr_fill.cc: Check
	feature test macro.
	* testsuite/23_containers/array/requirements/constexpr_iter.cc: Test
	in C++17 mode and check feature test macro.
2020-04-22 22:54:35 +01:00
Jonathan Wakely
c9313582d8 libstdc++: Update __cpp_lib_concepts value
* include/std/functional (__cpp_lib_concepts): Update macro value to
	indicate P1964R2 support.
	* include/std/version (__cpp_lib_concepts): Likewise.
	* testsuite/std/concepts/1.cc: Adjust expected value.
	* testsuite/std/concepts/2.cc: Likewise.
2020-04-22 22:54:34 +01:00
Jonathan Wakely
eca477d16c libstdc++: Rename __cpp_lib_constexpr_invoke macro
This macro was renamed after it was added to the working draft, but we
never renamed it  in libstdc++. We haven't made a release with the old
macro name, so I see no need to keep it around.

	* include/std/functional (__cpp_lib_constexpr_invoke): Rename to
	__cpp_lib_constexpr_functional.
	* include/std/version (__cpp_lib_constexpr_invoke): Likewise.
	* testsuite/20_util/function_objects/invoke/constexpr.cc: Adjust.
2020-04-22 22:54:34 +01:00
Jonathan Wakely
56772f623e libstdc++: Add missing feature test macros
These macros all correspond to features that are already supported, but
the macro was not defined when the feature was implemented.

	* include/bits/ptr_traits.h (__cpp_lib_constexpr_memory): Define to
	indicate P1006R1 support.
	(__cpp_lib_to_address): Define to indicate P0653R2 support.
	* include/bits/range_access.h (__cpp_lib_ssize): Define to indicate
	P1227R2 support.
	* include/bits/ranges_algo.h (__cpp_lib_shift): Define to indicate
	P0769R2 support.
	* include/std/atomic (__cpp_lib_atomic_float): Define to indicate
	P0020R6 support.
	* include/std/memory (__cpp_lib_assume_aligned): Define to indicate
	P1007R3 support.
	* include/std/memory_resource (__cpp_lib_polymorphic_allocator):
	Define to indicate P0339R6 support.
	* include/std/string_view (__cpp_lib_starts_ends_with): Define to
	indicate P0457R2 support.
	* include/std/type_traits (__cpp_lib_is_nothrow_convertible): Define
	to indicate P0758R1 support.
	(__cpp_lib_remove_cvref): Define to indicate P0550R2 support.
	(__cpp_lib_type_identity): Define to indicate P0887R1 support.
	* include/std/version (__cpp_lib_atomic_float)
	(__cpp_lib_is_nothrow_convertible, __cpp_lib_remove_cvref)
	(__cpp_lib_type_identity, __cpp_lib_assume_aligned)
	(__cpp_lib_constexpr_memory, __cpp_lib_polymorphic_allocator)
	(__cpp_lib_shift, __cpp_lib_ssize, __cpp_lib_starts_ends_with)
	(__cpp_lib_to_address): Define.
	* testsuite/20_util/to_address/1_neg.cc: Adjust dg-error line number.
2020-04-22 22:54:34 +01:00
Jonathan Wakely
0d2dbae406 libstdc++: Remove non-standard feature test macros
These macros were replaced by __cpp_lib_map_try_emplace and
__cpp_lib_unordered_map_try_emplace, because those names are more
descriptive. We've kept both old and new names so far, but I think we
can remove the old ones now.

	* include/bits/stl_map.h (__cpp_lib_map_insertion): Remove old
	macro.
	* include/bits/unordered_map.h (__cpp_lib_unordered_map_insertion):
	Likewise.
	* include/std/version (__cpp_lib_map_insertion)
	(__cpp_lib_unordered_map_insertion): Remove.
2020-04-22 22:54:34 +01:00
Jonathan Wakely
aa12ab2e93 libstdc++: Update value of __cpp_lib_jthread macro
* include/std/condition_variable (__cpp_lib_jthread): Remove
	redundant definition.
	* include/std/stop_token (__cpp_lib_jthread): Update macro value to
	indicate P1869R1 support.
	* include/std/version (__cpp_lib_jthread): Update value.
	* testsuite/30_threads/condition_variable_any/stop_token/1.cc: Check
	for updated macro value.
	* testsuite/30_threads/condition_variable_any/stop_token/2.cc:
	Likewise.
	* testsuite/30_threads/jthread/1.cc: Likewise.
	* testsuite/30_threads/jthread/2.cc: Likewise.
	* testsuite/30_threads/stop_token/1.cc: Likewise.
	* testsuite/30_threads/stop_token/2.cc: Likewise.
2020-04-22 22:54:34 +01:00