The deduced return type causes the instantiation of the function body,
which can then require the instantiation of std::projected::operator*
which is intentionally not defined.
This patch uses a helper trait to define the return type, so that the
function body doesn't need to be instantiated. That helper trait can
then also be used in other places that currently check the return type
of ranges::iter_move (iter_rvalue_reference_t and indirectly_readable).
2020-05-01 Jonathan Wakely <jwakely@redhat.com>
Patrick Palka <ppalka@redhat.com>
PR libstdc++/92894
* include/bits/iterator_concepts.h (ranges::__cust_imove::_IMove):
Add trait to determine return type and an alias for it.
(ranges::__cust_imove::_IMove::operator()): Use __result instead of
deduced return type.
(iter_rvalue_reference_t): Use _IMove::__type instead of checking
the result of ranges::iter_move.
(__detail::__indirectly_readable_impl): Use iter_rvalue_reference_t
instead of checking the result of ranges::iter_move.
* testsuite/24_iterators/customization_points/92894.cc: New test.
* testsuite/24_iterators/indirect_callable/92894.cc: New test.
The libstdc++ manual documents that _T can not be used, because it's a
macro in system headers on some targets.
PR libstdc++/94901
* include/std/type_traits (__is_complete_or_unbounded): Replace
BADNAME _T with _Tp.
* testsuite/17_intro/badnames.cc: New test.
This fixes a regression due to the conditional noexcept-specifier on
std::allocator::construct and std::allocator::destroy, as well as the
corresponding members of new_allocator, malloc_allocator, and
allocator_traits. Those noexcept-specifiers were using expressions which
might be ill-formed, which caused errors outside the immediate context
when checking for the presence of construct and destroy in SFINAE
contexts.
The fix is to use the is_nothrow_constructible and
is_nothrow_destructible type traits instead, because those traits are
safe to use even when the construction/destruction itself is not valid.
The is_nothrow_constructible trait will be false for a type that is not
also nothrow-destructible, even if the new-expression used in the
construct function body is actually noexcept. That's not the correct
answer, but isn't a problem because providing a noexcept-specifier on
these functions is not required by the standard anyway. If the answer is
false when it should be true, that's suboptimal but OK (unlike giving
errors for valid code, or giving a true answer when it should be false).
PR libstdc++/89510
* include/bits/alloc_traits.h (allocator_traits::_S_construct)
(allocator_traits::_S_destroy)
(allocator_traits<allocator<T>>::construct): Use traits in
noexcept-specifiers.
* include/bits/allocator.h (allocator<void>::construct)
(allocator<void>::destroy): Likewise.
* include/ext/malloc_allocator.h (malloc_allocator::construct)
(malloc_allocator::destroy): Likewise.
* include/ext/new_allocator.h (new_allocator::construct)
(new_allocator::destroy): Likewise.
* testsuite/20_util/allocator/89510.cc: New test.
* testsuite/ext/malloc_allocator/89510.cc: New test.
* testsuite/ext/new_allocator/89510.cc: New test.
By trying to reuse the existing std::_Construct function as a wrapper
for std::construct_at I introduced regressions, because changing
std::_Construct to return non-void made it ill-formed for array types.
The solution is to revert _Construct to its former state, and change
allocator_traits::construct to explicitly call construct_at instead.
This decouples all the existing callers of _Construct from the new
construct_at requirements.
PR libstdc++/94831
* include/bits/alloc_traits.h (_S_construct): Restore placement
new-expression for C++11/14/17 and call std::construct_at directly
for C++20.
* include/bits/stl_construct.h (_Construct): Revert to non-constexpr
function returning void.
* testsuite/20_util/specialized_algorithms/
uninitialized_value_construct/94831.cc: New test.
* testsuite/23_containers/vector/cons/94831.cc: New test.
This implements the proposed resolution of LWG 3433, which fixes
subrange::advance when called with a negative argument.
libstdc++-v3/ChangeLog:
LWG 3433 subrange::advance(n) has UB when n < 0
* include/std/ranges (subrange::prev): Fix typo.
(subrange::advance): Handle a negative argument as per the proposed
resolution of LWG 3433.
* testsuite/std/ranges/subrange/lwg3433.cc: New test.
From the standard:
The header <coroutine> defines the primary template coroutine_traits
such that if ArgTypes is a parameter pack of types and if the
qualified-id R::promise_type is valid and denotes a type, then
coroutine_traits<R,ArgTypes...> has the following publicly accessible
member:
using promise_type = typename R::promise_type;
this should not prevent more specialised cases and the following
code should be accepted, but is currently rejected with:
'error: coroutine return type ‘void’ is not a class'
This is because the check for non-class-ness of the return value was
in the wrong place; it needs to be carried out in a SFINAE context.
The following patch removes the restriction in the traits template
instantiation and allows for the case that the ramp function could
return void.
The <coroutine> header is amended to implement the required
functionality.
gcc/cp/ChangeLog:
2020-04-28 Iain Sandoe <iain@sandoe.co.uk>
PR c++/94759
* coroutines.cc (coro_promise_type_found_p): Do not
exclude non-classes here (this needs to be handled in the
coroutine header).
(morph_fn_to_coro): Allow for the case where the coroutine
returns void.
gcc/testsuite/ChangeLog:
2020-04-28 Iain Sandoe <iain@sandoe.co.uk>
PR c++/94759
* g++.dg/coroutines/coro-bad-alloc-00-bad-op-new.C: Adjust for
updated error messages.
* 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-missing-promise.C: Likewise.
* g++.dg/coroutines/pr93458-5-bad-coro-type.C: Liekwise.
* g++.dg/coroutines/torture/co-ret-17-void-ret-coro.C: New test.
libstdc++-v3/ChangeLog:
2020-04-28 Jonathan Wakely <jwakely@redhat.com>
Iain Sandoe <iain@sandoe.co.uk>
PR c++/94759
* include/std/coroutine: Implement handing for non-
class coroutine return types.
The LWG issue I created is Tentatively Ready and proposes to declare a
public default constructor, rather than the private one I added
recently.
* include/experimental/executor (service_already_exists): Make default
constructor public (LWG 3414).
* testsuite/experimental/net/execution_context/make_service.cc: Check
the service_already_exists can be default constructed.
This removes a non-standard extension to std::any which causes errors
for valid code, due to recursive instantiation of a trait that isn't
supposed to be in the constraints.
It also removes some incorrect constraints on the in_place_type<T>
constructors and emplace members, which were preventing creating a
std::any object with another std::any as the contained value.
2020-04-24 Kamlesh Kumar <kamleshbhalui@gmail.com>
Jonathan Wakely <jwakely@redhat.com>
PR libstdc++/90415
PR libstdc++/92156
* include/std/any (any): Rename template parameters for consistency
with the standard.
(any::_Decay): Rename to _Decay_if_not_any.
(any::any(T&&):: Remove is_constructible from constraints. Remove
non-standard overload.
(any::any(in_place_type_t<T>, Args&&...))
(any::any(in_place_type_t<T>, initializer_list<U>, Args&&...))
(any::emplace(Args&&...))
(any::emplace(initializer_list<U>, Args&&...)):
Use decay_t instead of _Decay.
* testsuite/20_util/any/cons/90415.cc: New test.
* testsuite/20_util/any/cons/92156.cc: New Test.
* testsuite/20_util/any/misc/any_cast_neg.cc: Make dg-error directives
more robust.
* testsuite/20_util/any/modifiers/92156.cc: New test.
* include/experimental/net/executor (system_context): Mark
system_context::system_context() = delete.
* testsuite/experimental/net/executor/1.cc: Add new
test to check system_context is not default constructible.
This reorganises the C++20 status table, grouping the proposals by
category. It also adds more proposals, and documents all the feature
test macros for C++20 library changes.
* doc/xml/manual/status_cxx2020.xml: Update C++20 status table.
* doc/html/*: Regenerate.
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.
The <compare> header is always supported, not only for hosted configs.
* include/std/version (__cpp_lib_three_way_comparison): Define for
freestanding builds.
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
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.
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.
The C++20 draft and SD-6 both say this should only be in <version> and
<algorithm>, not in <utility>.
* include/std/utility (__cpp_lib_constexpr_algorithms): Do not define
here.
* testsuite/20_util/exchange/constexpr.cc: Do not expect macro to be
defined by <utility>.
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.
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.
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.
This fixes a regression introduced when I replaced __normal_iterator's
relational operators with operator<=>. If the wrapped iterator type
doesn't define operator<=> then __normal_iterator doesdn't either, which
breaks any use of fancy pointers that don't define <=>. The regression
was found when trying to build cmcstl2.
The solution is to use synth-three-way to define __normal_iterator's
spaceship operator, so that it is still defined even if the wrapped type
only supports operator<.
* include/bits/stl_iterator.h (__normal_iterator): Use synth-three-way
to define operator<=>.
* testsuite/24_iterators/normal_iterator/cmp_c++20.cc: New test.
This adds a full table of contents for the C++14 and C++17 standards,
with status for each part.
For C++14 the list of proposals is removed, as it adds little value now
that everything is supported. For C++17 the table of proposals is
retained, because it documents he feature test macros for the features.
* doc/Makefile.am (xml_sources_manual): Add missing XML files.
* doc/Makefile.in: Regenerate.
* doc/xml/manual/status_cxx1998.xml: Refer to "this section" instead
of "this page".
* doc/xml/manual/status_cxx2011.xml: Formatting and other corrections
to the C++11 status table.
* doc/xml/manual/status_cxx2014.xml: Replace list of C++14 feature
proposals with table matching contents of the C++14 standard.
* doc/xml/manual/status_cxx2017.xml: Add table matching contents of
the C++17 standard.
* doc/html/*: Regenerate.
The front end now supports parenthesized initialization for arrays in
C++20, so extend std::is_nothrow_constructible to support them too.
gcc/testsuite:
PR c++/94149
* g++.dg/cpp2a/paren-init24.C: Fix FIXMEs.
libstdc++-v3:
PR c++/94149
* include/std/type_traits (__is_nt_constructible_impl): Add partial
specializations for bounded arrays with non-empty initializers.
* testsuite/20_util/is_nothrow_constructible/value_c++20.cc: New test.
* testsuite/lib/libstdc++.exp: Add additional_flags=
-DTBB_SUPRESS_DEPRECATED_MESSAGES=1 to suppress warnings when
compiling with a newer Thread Building Blocks.
This test was supposed to be added two months ago as part of commit
120e873484 but was omitted by mistake.
* testsuite/24_iterators/istreambuf_iterator/sentinel.cc: New test.
* testsuite/20_util/is_constructible/51185.cc: Make test class a
non-aggregate so that the test verifies the same thing in all -std
modes.
* testsuite/20_util/is_constructible/value-2.cc: Adjust expected
results for some types when paren-init for aggregates is supported.
After committing it I noticed I'd also accidentally added a change to
__synth3way as well, which I meant to do in a separate commit. I've
updated the changelog entry to reflect that additional change.
* libsupc++/compare (__detail::__synth3way): Add noexcept-specifier.
With P1614R2 fully implemented (except for the <chrono> types which we
don't support at all) we can define the feature test macro to the new
value.
* include/std/version (__cpp_lib_three_way_comparison): Update value.
* libsupc++/compare (__cpp_lib_three_way_comparison): Likewise.
If extra_tool_flags starts with a dash, an error like 'ERROR: verbose:
illegal argument: -march=native -O2 -std=c++17' is printed. This is
easily fixed by inserting a double dash before the variable.
2020-04-20 Matthias Kretz <kretz@kde.org>
* testsuite/lib/libstdc++.exp: Avoid illegal argument to verbose.
Some more C++20 changes from P1614R2, "The Mothership has Landed".
* include/bits/stl_queue.h (queue): Define operator<=> for C++20.
* include/bits/stl_stack.h (stack): Likewise.
* testsuite/23_containers/queue/cmp_c++20.cc: New test.
* testsuite/23_containers/stack/cmp_c++20.cc: New test.
This appears to be a copy&paste error, which cppcheck diagnoses.
PR other/94629
* include/debug/formatter.h (_Error_formatter::_Parameter): Fix
redundant assignment in constructor.
Some more C++20 changes from P1614R2, "The Mothership has Landed".
* include/std/chrono (duration, time_point): Define operator<=> and
remove redundant operator!= for C++20.
* testsuite/20_util/duration/comparison_operators/three_way.cc: New
test.
* testsuite/20_util/time_point/comparison_operators/three_way.cc: New
test.
In C++20 the rebind and const_reference members of std::allocator are
gone, so this testsuite utility stopped working, causing
ext/pb_ds/regression/priority_queue_rand_debug.cc to FAIL.
* testsuite/util/native_type/native_priority_queue.hpp: Use
allocator_traits to rebind allocator.
Some more C++20 changes from P1614R2, "The Mothership has Landed".
This adds three-way comparison support to std::char_traits,
std::basic_string, std::basic_string_view, and std::sub_match.
* include/bits/basic_string.h (basic_string): Define operator<=> and
remove redundant comparison operators for C++20.
* include/bits/char_traits.h (__gnu_cxx::char_traits, char_traits):
Add comparison_category members.
(__detail::__char_traits_cmp_cat): New helper to get comparison
category from char traits class.
* include/bits/regex.h (regex_traits::_RegexMask::operator!=): Do not
define for C++20.
(sub_match): Define operator<=> and remove redundant comparison
operators for C++20.
(match_results): Remove redundant operator!= for C++20.
* include/std/string_view (basic_string_view): Define operator<=> and
remove redundant comparison operators for C++20.
* testsuite/21_strings/basic_string/operators/char/cmp_c++20.cc: New
test.
* testsuite/21_strings/basic_string/operators/wchar_t/cmp_c++20.cc:
New test.
* testsuite/21_strings/basic_string_view/operations/copy/char/
constexpr.cc: Initialize variable.
* testsuite/21_strings/basic_string_view/operations/copy/wchar_t/
constexpr.cc: Likewise.
* testsuite/21_strings/basic_string_view/operators/char/2.cc: Add
dg-do directive and remove comments showing incorrect signatures.
* testsuite/21_strings/basic_string_view/operators/wchar_t/2.cc:
Likewise.
* testsuite/21_strings/basic_string_view/operators/char/cmp_c++20.cc:
New test.
* testsuite/21_strings/basic_string_view/operators/wchar_t/cmp_c++20.cc:
New test.
* testsuite/28_regex/sub_match/compare_c++20.cc: New test.
Some more C++20 changes from P1614R2, "The Mothership has Landed".
This removes all redundant equality and inequality operators in the
Utilities clause, as they can be synthesized from the remaining equality
operators.
It also removes the single redundant operator in the Localization
clause, because it didn't seem worth doing in a separate commit.
* include/bits/allocator.h (operator!=): Do not define for C++20.
* include/bits/locale_classes.h (operator!=): Likewise.
* include/bits/std_function.h (operator==(nullptr_t, const function&))
(operator!=(const function&, nullptr_t))
(operator!=(nullptr_t, const function&)): Likewise.
* include/ext/bitmap_allocator.h (operator!=): Likewise.
* include/ext/debug_allocator.h (operator!=): Likewise.
* include/ext/extptr_allocator.h (operator!=): Likewise.
* include/ext/malloc_allocator.h (operator!=): Likewise.
* include/ext/mt_allocator.h (operator!=): Likewise.
* include/ext/new_allocator.h (operator!=): Likewise.
* include/ext/pool_allocator.h (operator!=): Likewise.
* include/ext/throw_allocator.h (operator!=): Likewise.
* include/std/bitset (bitset::operator!=): Likewise.
* include/std/memory_resource (operator!=): Likewise.
* include/std/scoped_allocator (operator!=): Likewise.
Another C++20 change from P1614R2, "The Mothership has Landed".
* include/std/typeindex (operator<=>): Define for C++20.
* testsuite/20_util/typeindex/comparison_operators_c++20.cc: New test.
My "simplification" of std::compare_three_way's constraints in commit
f214ffb336 was incorrect, because
std::three_way_comparable_with imposes additional restrictions beyond
the <=> expression being valid.
* libsupc++/compare (compare_three_way): Fix constraint so that
BUILTIN-PTR-THREE-WAY does not require three_way_comparable_with.
* testsuite/18_support/comparisons/object/builtin-ptr-three-way.cc:
New test.
This also implements the proposed resolution to LWG issue 3247, so that
the ill-formed <=> expression with nullptr is not used.
PR libstdc++/94562
* include/bits/shared_ptr.h (operator<=>): Define for C++20.
* include/bits/shared_ptr_base.h (operator<=>): Likewise.
* include/bits/unique_ptr.h (operator<=>): Add inline specifier.
* testsuite/20_util/shared_ptr/comparison/cmp_c++20.cc: New test.
* testsuite/20_util/shared_ptr/comparison/less.cc: Do not expect
std::less<A*> to be used when comparing std::shared_ptr<A> objects in
C++20.
