Daily bump.

[thirdparty/gcc.git] / libstdc++-v3 / ChangeLog

2021-10-22  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/102894
        * include/std/any (make_any): Add SFINAE constraint.
        * testsuite/20_util/any/102894.cc: New test.

2021-10-21  Jonathan Wakely  <jwakely@redhat.com>

        * doc/doxygen/stdheader.cc: Refactor. Use C++23. Add new
        headers.
        * scripts/run_doxygen: Fix post-processing of #include
        directives in man pages. Use new xg++ to compile helper program.

2021-10-21  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/mofunc_impl.h: Add doxygen comments.
        * include/std/functional: Likewise.

2021-10-21  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/alloc_traits.h: Suppress doxygen documentation.
        * include/bits/allocated_ptr.h: Likewise.
        * include/bits/enable_special_members.h: Likewise.
        * include/bits/hashtable.h: Likewise.
        * include/bits/hashtable_policy.h: Likewise.
        * include/bits/uses_allocator.h: Likewise.
        * include/bits/node_handle.h: Document node handles and suppress
        documentation for protected members.
        * include/std/any: Suppress documentation for implementation
        details.

2021-10-21  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/102358
        * include/bits/stl_iterator.h (__niter_base): Make constexpr
        for C++20.
        (__miter_base): Likewise.
        * testsuite/25_algorithms/move/constexpr.cc: New test.

2021-10-21  Patrick Palka  <ppalka@redhat.com>

        * include/std/ranges (istream_view): Replace this function
        template with an alias template as per P2432R1.
        (wistream_view): Define as per P2432R1.
        (views::_Istream, views::istream): Likewise.
        * testsuite/std/ranges/istream_view.cc (test07): New test.

2021-10-21  Patrick Palka  <ppalka@redhat.com>

        * include/bits/ranges_util.h (views::_Drop): Forward declare.
        (subrange): Befriend views::_Drop.
        (subrange::_S_store_size): Declare constexpr instead of just
        const, remove obsolete comment.
        * include/std/ranges (views::__detail::__is_empty_view): Define.
        (views::__detail::__is_basic_string_view): Likewise.
        (views::__detail::__is_subrange): Likewise.
        (views::__detail::__is_iota_view): Likewise.
        (views::__detail::__can_take_view): Rename template parm _Tp to _Dp.
        (views::_Take): Rename template parm _Tp to _Dp, make it non-deducible
        and fix it to range_difference_t<_Range>.  Implement P1739R4 and
        LWG 3407 changes.
        (views::__detail::__can_drop_view): Rename template parm _Tp to _Dp.
        (views::_Drop): As with views::_Take.
        (views::_Counted): Implement P1739R4 changes.
        * include/std/span (__detail::__is_std_span): Rename to ...
        (__detail::__is_span): ... this and turn it into a variable
        template.
        (__detail::__is_std_array): Turn it into a variable template.
        (span::span): Adjust uses of __is_std_span and __is_std_array
        accordingly.
        * testsuite/std/ranges/adaptors/p1739.cc: New test.

2021-10-21  Patrick Palka  <ppalka@redhat.com>

        * include/bits/stl_iterator.h (common_iterator::__arrow_proxy):
        Make fully constexpr as per LWG 3595.
        (common_iterator::__postfix_proxy): Likewise.

2021-10-21  Patrick Palka  <ppalka@redhat.com>

        * include/std/ranges (lazy_split_view::base): Add forward_range
        constraint as per LWG 3591.
        (lazy_split_view::begin, lazy_split_view::end): Also check
        simpleness of _Pattern as per LWG 3592.
        (split_view::base): Relax copyable constraint as per LWG 3590.

2021-10-21  Patrick Palka  <ppalka@redhat.com>

        * include/std/ranges (join_view::__iter_cat::_S_iter_cat): Adjust
        criteria for returning bidirectional_iterator_tag as per LWG 3535.
        (join_view::_Iterator::_S_iter_concept): Likewise.

2021-10-21  Patrick Palka  <ppalka@redhat.com>

        * include/bits/ranges_base.h (viewable_range): Adjust as per
        LWG 3481.
        * testsuite/std/ranges/adaptors/all.cc (test07): New test.

2021-10-21  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/102863
        * include/std/optional (optional::and_then, optional::transform):
        Remove requires-clause.
        * testsuite/20_util/optional/monadic/and_then.cc: Check
        overload resolution doesn't cause errors.
        * testsuite/20_util/optional/monadic/transform.cc: Likewise.

2021-10-20  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/20_util/optional/monadic/transform.cc: Check that
        an rvalue result is not materialized too soon.

2021-10-19  Patrick Palka  <ppalka@redhat.com>

        * include/std/ranges (iota_view::_Iterator::operator+): Adjust
        definition as per LWG 3580.
        (iota_view::_Iterator::operator-): Likewise.

2021-10-19  Patrick Palka  <ppalka@redhat.com>

        * include/std/ranges (basic_istream_view::_M_object): Value
        initialize as per LWG 3568.

2021-10-19  Patrick Palka  <ppalka@redhat.com>

        * include/bits/ranges_util.h
        (__detail::__uses_nonqualification_pointer_conversion): Define
        and use it ...
        (__detail::__convertible_to_nonslicing): ... here, as per LWG 3470.
        * testsuite/std/ranges/subrange/1.cc: New test.

2021-10-19  Patrick Palka  <ppalka@redhat.com>

        * include/std/ranges (iota_view::_Iterator): Befriend iota_view.
        (iota_view::_Sentinel): Likewise.
        (iota_view::iota_view): Add three overloads, each taking an
        iterator/sentinel pair as per LWG 3523.
        * testsuite/std/ranges/iota/iota_view.cc (test06): New test.

2021-10-19  Patrick Palka  <ppalka@redhat.com>

        * include/bits/ranges_base.h (view_interface): Forward declare.
        (__detail::__is_derived_from_view_interface_fn): Declare.
        (__detail::__is_derived_from_view_interface): Define as per LWG 3549.
        (enable_view): Adjust as per LWG 3549.
        * include/bits/ranges_util.h (view_interface): Don't derive from
        view_base.
        * include/std/ranges (filter_view): Revert r11-3504 change.
        (transform_view): Likewise.
        (take_view): Likewise.
        (take_while_view): Likewise.
        (drop_view): Likewise.
        (drop_while_view): Likewise.
        (join_view): Likewise.
        (lazy_split_view): Likewise.
        (split_view): Likewise.
        (reverse_view): Likewise.
        * testsuite/std/ranges/adaptors/sizeof.cc: Update expected sizes.
        * testsuite/std/ranges/view.cc (test_view::test_view): Remove
        this default ctor since views no longer need to be default initable.
        (test01): New test.

2021-10-19  Jonathan Wakely  <jwakely@redhat.com>

        * src/c++11/random.cc (which_source): New helper function.
        (random_device::_M_getentropy()): Use which_source and return
        suitable values for sources other than device files.
        * testsuite/26_numerics/random/random_device/entropy.cc: New test.

2021-10-19  Jonathan Wakely  <jwakely@redhat.com>

        * doc/Makefile.am (stamp-html-doxygen, stamp-html-doxygen)
        (stamp-latex-doxygen, stamp-man-doxygen): Fix recipes for
        relative ${top_srcdir}.
        * doc/Makefile.in: Regenerate.

2021-10-19  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/variant (_Uninitialized): Use an empty struct
        for the unused union member, instead of char.

2021-10-19  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/stl_stack.h (stack(Iterator, Iterator)): Remove
        non-deducible template parameter from deduction guide.
        * testsuite/23_containers/stack/deduction.cc: Check new C++23
        deduction guides.

2021-10-19  Jonathan Wakely  <jwakely@redhat.com>

        * 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  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/102825
        * include/bits/mofunc_impl.h (move_only_function): Remove
        invalid base initializer.
        * testsuite/20_util/move_only_function/cons.cc: Instantiate
        constructors to check bodies.

2021-10-15  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/fs_path.h (path::_S_convert(T)): Avoid recursive
        call to function with deduced return type.

2021-10-15  Jonathan Wakely  <jwakely@redhat.com>

        * 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.

2021-10-15  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101263
        * include/std/ranges (__cached): New wrapper struct.
        (__non_propagating_cache): Use __cached for contained value.
        (__non_propagating_cache::_M_emplace_deref): Add constexpr. Use
        std::construct_at instead of placement new.
        * testsuite/std/ranges/adaptors/join.cc: Check constexpr works.

2021-10-15  Jonathan Wakely  <jwakely@redhat.com>

        * 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  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/variant (__detail::__variant::__get_storage):
        Remove unused function.
        (__variant_construct_by_index): Set index after construction is
        complete. Rename to ...
        (__detail::__variant::__construct_by_index): ... this.
        (variant): Use new name for __variant_construct_by_index friend
        declaration. Remove __get_storage friend declaration.
        (variant::emplace): Use new name and remove try-blocks.

2021-10-15  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/variant (_Variant_storage::_M_storage()): Remove.
        (__detail::__variant::__get_storage): Remove.
        (variant): Remove friend declaration of __get_storage.

2021-10-15  Jason Merrill  <jason@redhat.com>

        * testsuite/20_util/integer_comparisons/greater_equal_neg.cc:
        * testsuite/20_util/integer_comparisons/greater_neg.cc:
        * testsuite/20_util/integer_comparisons/less_equal_neg.cc:
        Adjust expected message.
        * testsuite/lib/prune.exp: Prune 'in constexpr expansion'.

2021-10-14  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/variant (__variant::__get(in_place_index_t<N>, U&&)):
        Rename to __get_n and remove first argument. Replace pair of
        overloads with a single function using 'if constexpr'.
        (__variant::__get(Variant&&)): Adjust to use __get_n.

2021-10-14  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/fs_path.h (path(path&&)): Make unconditionally
        noexcept.
        (path::_S_convert(T)): Add condtional noexcept.

2021-10-14  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/102743
        * include/bits/fs_path.h (path::_S_convert(T)): Fix condition
        for returning the same string unchanged.

2021-10-14  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/regex.h: Check __cpp_inline_variables instead of
        __cplusplus.

2021-10-14  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/20_util/is_layout_compatible/version.cc: Check
        correct macro.

2021-10-14  Jonathan Wakely  <jwakely@redhat.com>

        * 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.

2021-10-13  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/fs_path.h (__detail::__is_contiguous): Add
        partial specializations for pointers and __normal_iterator.

2021-10-13  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/27_io/filesystem/path/construct/102592.C: Moved to...
        * testsuite/27_io/filesystem/path/construct/102592.cc: ...here.
        * testsuite/28_regex/match_results/102667.C: Moved to...
        * testsuite/28_regex/match_results/102667.cc: ...here.

2021-10-13  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/fs_path.h (__detail::__is_contiguous): New
        variable template to identify contiguous iterators.
        (__detail::__unified_char8_t): New alias template to decide when
        to treat char8_t as char without encoding conversion.
        (__detail::__effective_range(const basic_string<C,T>&)): Use
        std::char_traits<C> for returned string view.
        (__detail::__effective_range(const basic_string_view<C,T>&)):
        Likewise.
        (__detail::__effective_range(const Source&)): Use
        __is_contiguous to detect mode cases of contiguous iterators.
        Use __unified_char8_t to return a std::string instead of
        std::u8string.

2021-10-13  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/102592
        * include/bits/fs_path.h (path::path(Iter, Iter, format))
        (path::append(Iter, Iter), path::concat(Iter, Iter)): Call
        __string_from_range directly, instead of two-argument overload
        of _S_convert.
        (path::_S_convert(Iter, Iter)): Remove.
        * testsuite/27_io/filesystem/path/construct/102592.C: New test.

2021-10-13  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/c++config (__terminate): Add extern "C++".

2021-10-12  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/20_util/tuple/comparison_operators/overloaded.cc:
        Restore test for operator<.
        * testsuite/20_util/tuple/comparison_operators/overloaded2.cc:
        Adjust expected errors for C++20.

2021-10-12  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101960
        * include/std/tuple (_Tuple_impl(_Tuple_impl&&)): Define as
        defauled.
        * testsuite/20_util/tuple/cons/101960.cc: Check tuples with
        array elements before the last element.

2021-10-12  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/stl_iterator_base_funcs.h (__advance): Add
        deleted overload to improve diagnostics.
        (__distance): Likewise.

2021-10-11  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/atomic_timed_wait.h: Remove unused header.
        * include/bits/c++config (std:__terminate): Define.
        * include/bits/semaphore_base.h: Remove <exception> and use
        __terminate instead of terminate.
        * include/bits/std_thread.h: Likewise.
        * libsupc++/eh_terminate.cc (std::terminate): Use qualified-id
        to call __cxxabiv1::__terminate.

2021-10-11  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/regex.h (basic_regex::assign(Iter, Iter)): Avoid
        std::__to_address by using poitner directly or using base()
        member of __normal_iterator.

2021-10-11  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/18_support/numeric_limits/lowest.cc: Use
        numeric_limits<T>::is_integer instead of is_integral<T>::value.

2021-10-11  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/89927
        * include/bits/regex.h (basic_regex(const _Ch_type*, size_t)):
        Add __glibcxx_requires_string_len assertion.
        (basic_regex::assign(InputIterator, InputIterator)): Add
        __glibcxx_requires_valid_range assertion.
        * include/bits/regex_scanner.tcc (_Scanner::_M_advance())
        (_Scanner::_M_scan_normal()): Use string literal in assertions.

2021-10-11  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/102667
        * include/bits/regex.h (match_result::empty()): Optimize by
        calling the base function directly.
        (match_results::end()): Check _Base_type::empty() not empty().
        * testsuite/28_regex/match_results/102667.C: New test.

2021-10-08  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/98725
        * testsuite/18_support/numeric_limits/lowest.cc: Remove use of
        _GLIBCXX_USE_WCHAR_T.
        * testsuite/18_support/numeric_limits/min_max.cc: Replace use of
        _GLIBCXX_USE_WCHAR_T with checks for WCHAR_MIN and WCHAR_MAX.
        * testsuite/20_util/from_chars/1_neg.cc: Remove use of
        _GLIBCXX_USE_WCHAR_T.
        * testsuite/20_util/function_objects/searchers.cc: Likewise. Use
        char_traits<wchar_t>::length instead of wcslen.
        * testsuite/20_util/hash/requirements/explicit_instantiation.cc:
        Likewise.
        * testsuite/20_util/is_arithmetic/value.cc: Likewise.
        * testsuite/20_util/is_compound/value.cc: Likewise.
        * testsuite/20_util/is_floating_point/value.cc: Likewise.
        * testsuite/20_util/is_fundamental/value.cc: Likewise.
        * testsuite/20_util/is_integral/value.cc: Likewise.
        * testsuite/20_util/is_signed/value.cc: Likewise.
        * testsuite/20_util/is_unsigned/value.cc: Likewise.
        * testsuite/20_util/is_void/value.cc: Likewise.
        * testsuite/20_util/make_signed/requirements/typedefs-1.cc:
        Likewise.
        * testsuite/20_util/make_signed/requirements/typedefs-2.cc:
        Likewise.
        * testsuite/20_util/make_signed/requirements/typedefs-3.cc:
        Likewise.
        * testsuite/20_util/make_signed/requirements/typedefs-4.cc:
        Likewise.
        * testsuite/20_util/make_unsigned/requirements/typedefs-1.cc:
        Likewise.
        * testsuite/20_util/make_unsigned/requirements/typedefs-2.cc:
        Likewise.
        * testsuite/20_util/make_unsigned/requirements/typedefs-3.cc:
        Likewise.
        * testsuite/20_util/to_chars/3.cc: Likewise.
        * testsuite/20_util/type_identity/requirements/typedefs.cc:
        Likewise.
        * testsuite/21_strings/basic_string/hash/debug.cc: Likewise.
        * testsuite/21_strings/basic_string/hash/hash.cc: Likewise.
        * testsuite/21_strings/basic_string/literals/types-char8_t.cc:
        Likewise.
        * testsuite/21_strings/basic_string/literals/types.cc: Likewise.
        * testsuite/21_strings/basic_string/literals/values-char8_t.cc:
        Likewise.
        * testsuite/21_strings/basic_string/literals/values.cc:
        Likewise.
        * testsuite/21_strings/basic_string/modifiers/64422.cc:
        Likewise.
        * testsuite/21_strings/basic_string/range_access/wchar_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string/requirements/citerators.cc:
        Likewise.
        * testsuite/21_strings/basic_string/requirements/typedefs.cc:
        Likewise.
        * testsuite/21_strings/basic_string/types/pmr_typedefs.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/literals/types-char8_t.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/literals/types.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/literals/values-char8_t.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/literals/values.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/requirements/typedefs.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/typedefs.cc: Likewise.
        * testsuite/21_strings/char_traits/requirements/constexpr_functions.cc:
        Likewise.
        * testsuite/21_strings/char_traits/requirements/constexpr_functions_c++17.cc:
        Likewise.
        * testsuite/21_strings/char_traits/requirements/constexpr_functions_c++20.cc:
        Likewise.
        * testsuite/22_locale/ctype/is/string/89728_neg.cc: Likewise.
        * testsuite/25_algorithms/fill/4.cc: Likewise.
        * testsuite/25_algorithms/fill_n/1.cc: Likewise.
        * testsuite/experimental/functional/searchers.cc: Likewise. Use
        char_traits<wchar_t>::length instead of wcslen.
        * testsuite/experimental/polymorphic_allocator/pmr_typedefs_string.cc:
        Likewise.
        * testsuite/experimental/string_view/literals/types-char8_t.cc:
        Likewise.
        * testsuite/experimental/string_view/literals/types.cc:
        Likewise.
        * testsuite/experimental/string_view/literals/values-char8_t.cc:
        Likewise.
        * testsuite/experimental/string_view/literals/values.cc:
        Likewise.
        * testsuite/experimental/string_view/range_access/wchar_t/1.cc:
        Likewise.
        * testsuite/experimental/string_view/requirements/typedefs.cc:
        Likewise.
        * testsuite/experimental/string_view/typedefs.cc: Likewise.
        * testsuite/ext/vstring/range_access.cc: Likewise.
        * testsuite/std/concepts/concepts.lang/concept.arithmetic/integral.cc:
        Likewise.
        * testsuite/std/concepts/concepts.lang/concept.arithmetic/signed_integral.cc:
        Likewise.
        * testsuite/std/concepts/concepts.lang/concept.arithmetic/unsigned_integral.cc:
        Likewise.
        * testsuite/tr1/4_metaprogramming/is_arithmetic/value.cc:
        Likewise.
        * testsuite/tr1/4_metaprogramming/is_compound/value.cc:
        Likewise.
        * testsuite/tr1/4_metaprogramming/is_floating_point/value.cc:
        Likewise.
        * testsuite/tr1/4_metaprogramming/is_fundamental/value.cc:
        Likewise.
        * testsuite/tr1/4_metaprogramming/is_integral/value.cc:
        Likewise.
        * testsuite/tr1/4_metaprogramming/is_signed/value.cc: Likewise.
        * testsuite/tr1/4_metaprogramming/is_unsigned/value.cc:
        Likewise.
        * testsuite/tr1/4_metaprogramming/is_void/value.cc: Likewise.
        * testsuite/tr1/6_containers/hash/24799.cc: Likewise.

2021-10-08  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/98725
        * include/std/ostream (operator<<(basic_ostream<char, Tr>&, wchar_t))
        (operator<<(basic_ostream<char, Tr>&, const wchar_t*)): Always
        define as deleted. Do not check _GLIBCXX_USE_WCHAR_T.

2021-10-08  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/98725
        * include/bits/locale_conv.h (wstring_convert, wbuffer_convert):
        Define unconditionally. Do not check _GLIBCXX_USE_WCHAR_T.

2021-10-08  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/98725
        * include/c_global/cstddef [!_GLIBCXX_USE_WCHAR_T]
        (__byte_operand<wchar_t>): Define specialization.
        * include/std/type_traits (__make_signed<wchar_t>)
        (__make_unsigned<wchar_t>): Remove redundant check for
        __WCHAR_TYPE__ being defined.
        * include/tr1/type_traits [!_GLIBCXX_USE_WCHAR_T]
        (__is_integral_helper<wchar_t>): Likewise.

2021-10-08  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/98725
        * include/ext/rc_string_base.h [!_GLIBCXX_USE_WCHAR_T]
        (__rc_string_base<wchar_t>): Define member function.
        * include/ext/vstring.h [!_GLIBCXX_USE_WCHAR_T]
        (hash<__gnu_cxx::__wvstring>): Define specialization.
        * include/ext/vstring_fwd.h [!_GLIBCXX_USE_WCHAR_T] (__wvstring)
        (__wsso_string, __wrc_string): Declare typedefs.

2021-10-08  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/98725
        * include/bits/char_traits.h (char_traits<wchar_t>): Define
        explicit specialization unconditionally.
        * include/bits/basic_string.h (hash<wstring>): Define
        unconditionally. Do not check _GLIBCXX_USE_WCHAR_T.
        * include/bits/stringfwd.h (wstring): Likewise.
        * include/debug/string (wstring): Likewise.
        * include/experimental/string_view (experimental::wstring_view)
        (hash<experimental::wstring_view>): Likewise.
        * include/std/string (pmr::wstring, hash<pmr::wstring>):
        Likewise.
        * include/std/string_view (wstring_view, hash<wstring_view>):
        Likewise.

2021-10-08  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/27_io/basic_filebuf/close/81256.cc: Moved to...
        * testsuite/27_io/basic_filebuf/close/wchar_t/81256.cc: ...here.

2021-10-08  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/22_locale/conversions/buffer/1.cc: Check
        _GLIBCXX_USE_WCHAR_T.
        * testsuite/22_locale/conversions/buffer/3.cc: Likewise. Add
        test using char16_t.
        * testsuite/22_locale/conversions/string/1.cc: Check
        _GLIBCXX_USE_WCHAR_T.
        * testsuite/27_io/filesystem/path/generic/generic_string.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/modifiers/make_preferred.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/native/alloc.cc: Likewise.
        * testsuite/27_io/filesystem/path/native/string-char8_t.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/native/string.cc: Likewise.
        * testsuite/28_regex/algorithms/regex_match/extended/wstring_locale.cc:
        Likewise.
        * testsuite/experimental/filesystem/path/generic/generic_string.cc:
        Likewise.
        * testsuite/experimental/filesystem/path/native/alloc.cc:
        Likewise.
        * testsuite/experimental/filesystem/path/native/string-char8_t.cc:
        Likewise.
        * testsuite/experimental/filesystem/path/native/string.cc:
        Likewise.

2021-10-08  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/26_numerics/bit/bit.rotate/rotr.cc:
        * testsuite/util/testsuite_common_types.h:

2021-10-08  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/18_support/numeric_limits/40856.cc: Replace use of
        _GLIBCXX_USE_INT128.
        * testsuite/18_support/numeric_limits/dr559.cc: Likewise.
        * testsuite/18_support/numeric_limits/lowest.cc: Likewise.
        * testsuite/18_support/numeric_limits/max_digits10.cc: Likewise.
        * testsuite/20_util/is_floating_point/value.cc: Likewise.
        * testsuite/20_util/is_integral/value.cc: Likewise.
        * testsuite/20_util/is_signed/value.cc: Likewise.
        * testsuite/20_util/is_unsigned/value.cc: Likewise.
        * testsuite/20_util/make_signed/requirements/typedefs-1.cc:
        Likewise.
        * testsuite/20_util/make_signed/requirements/typedefs-2.cc:
        Likewise.
        * testsuite/20_util/make_unsigned/requirements/typedefs-1.cc:
        Likewise.
        * testsuite/20_util/make_unsigned/requirements/typedefs-2.cc:
        Likewise.
        * testsuite/20_util/type_identity/requirements/typedefs.cc:
        Likewise.
        * testsuite/26_numerics/bit/bit.count/countl_one.cc: Likewise.
        * testsuite/26_numerics/bit/bit.count/countl_zero.cc: Likewise.
        * testsuite/26_numerics/bit/bit.count/countr_one.cc: Likewise.
        * testsuite/26_numerics/bit/bit.count/countr_zero.cc: Likewise.
        * testsuite/26_numerics/bit/bit.count/popcount.cc: Likewise.
        * testsuite/26_numerics/bit/bit.pow.two/bit_ceil.cc: Likewise.
        * testsuite/26_numerics/bit/bit.pow.two/bit_floor.cc: Likewise.
        * testsuite/26_numerics/bit/bit.pow.two/bit_width.cc: Likewise.
        * testsuite/26_numerics/bit/bit.pow.two/has_single_bit.cc:
        Likewise.
        * testsuite/26_numerics/bit/bit.rotate/rotl.cc: Likewise.

2021-10-08  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/hashtable_policy.h (_Select1st): Replace use of
        std::get.
        (_Select2nd): Remove.
        (_NodeBuilder::_S_build): Use _NodeGenerator::__node_type
        typedef instead of deducing it. Remove unnecessary piecewise
        construction.
        (_ReuseOrAllocNode): Make __node_type public.
        (_Map_base): Adjust partial specialization to be able to extract
        the mapped_type without using tuple_element.
        (_Map_base::at): Define inline
        * testsuite/23_containers/unordered_map/requirements/53339.cc:
        Remove XFAIL.
        * testsuite/23_containers/unordered_multimap/requirements/53339.cc:
        Likewise.

2021-10-08  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/hashtable.h: Move static assertion to destructor.
        * include/bits/hashtable_policy.h: Deduce value type from node
        type without instantiating it.

2021-10-08  Jonathan Wakely  <jwakely@redhat.com>

        * src/c++11/limits.cc: Fail if __cpp_inline_variables is
        defined.

2021-10-08  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/92546
        * include/bits/ranges_algobase.h: Replace <iterator> with a
        subset of the headers it includes.

2021-10-08  Jonathan Wakely  <jwakely@redhat.com>

        * include/experimental/deque (erase, erase_if): Revert changes
        to avoid debug mode overhead.
        * include/experimental/map (erase, erase_if): Likewise.
        * include/experimental/set (erase, erase_if): Likewise.
        * include/experimental/unordered_map (erase, erase_if):
        Likewise.
        * include/experimental/unordered_set (erase, erase_if):
        Likewise.
        * include/experimental/vector (erase, erase_if): Likewise.
        * include/std/deque (erase, erase_if): Likewise.
        * include/std/map (erase, erase_if): Likewise.
        * include/std/set (erase, erase_if): Likewise.
        * include/std/unordered_map (erase, erase_if): Likewise.
        * include/std/unordered_set (erase, erase_if): Likewise.
        * include/std/vector (erase, erase_if): Likewise.

2021-10-08  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/chrono (__detail::__units_suffix_misc): New
        helper function.
        (__detail::__units_suffix): Likewise.
        (chrono::operator<<(basic_ostream&, const duration&)): Define.
        * testsuite/20_util/duration/io.cc: New test.

2021-10-07  Jonathan Wakely  <jwakely@redhat.com>

        * include/Makefile.am: Add new header.
        * include/Makefile.in: Regenerate.
        * include/std/chrono (duration, time_point, system_clock)
        (steady_clock, high_resolution_clock, chrono_literals, sys_time)
        (file_clock, file_time): Move to ...
        * include/bits/chrono.h: New file.
        * include/bits/atomic_futex.h: Include new header instead of
        <chrono>.
        * include/bits/atomic_timed_wait.h: Likewise.
        * include/bits/fs_fwd.h: Likewise.
        * include/bits/semaphore_base.h: Likewise.
        * include/bits/this_thread_sleep.h: Likewise.
        * include/bits/unique_lock.h: Likewise.
        * include/experimental/bits/fs_fwd.h: Likewise.
        * include/experimental/chrono: Likewise.
        * include/experimental/io_context: Likewise.
        * include/experimental/netfwd: Likewise.
        * include/experimental/timer: Likewise.
        * include/std/condition_variable: Likewise.
        * include/std/mutex: Likewise.
        * include/std/shared_mutex: Likewise.

2021-10-07  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/102377
        * include/bits/atomic_wait.h (__waiter_pool_base:_S_align):
        Hardcode to 64 instead of using non-constant constant.

2021-10-07  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/erase_if.h (__erase_nodes_if): Remove redundant
        __niter_base calls.
        * include/std/string (erase, erase_if): Likewise.
        * include/std/deque (erase, erase_if): Access non-debug
        container directly.
        * include/std/map (erase, erase_if): Likewise.
        * include/std/set (erase, erase_if): Likewise.
        * include/std/unordered_map (erase, erase_if): Likewise.
        * include/std/unordered_set (erase, erase_if): Likewise.
        * include/std/vector (erase, erase_if): Likewise.
        * include/experimental/deque (erase, erase_if): Likewise.
        * include/experimental/map (erase, erase_if): Likewise.
        * include/experimental/set (erase, erase_if): Likewise.
        * include/experimental/unordered_map (erase, erase_if):
        Likewise.
        * include/experimental/unordered_set (erase, erase_if):
        Likewise.
        * include/experimental/vector (erase, erase_if): Likewise.

2021-10-06  Jonathan Wakely  <jwakely@redhat.com>

        * 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.

2021-10-05  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/21_strings/basic_string_view/requirements/trivially_copyable.cc:
        New test.
        * testsuite/23_containers/span/trivially_copyable.cc: New test.

2021-10-05  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/utility.h (__is_in_place_type_v): Define
        variable template to detect in_place_type_t specializations.
        (__is_in_place_type): Replace class template with alias
        template using __is_in_place_type_v.
        * include/std/any (any(T&&)): Check __is_in_place_type first and
        avoid instantiating is_copy_constructible unnecessarily.

2021-10-05  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/20_util/integer_comparisons/greater.cc: New test.

2021-10-05  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/27_io/basic_ostream/inserters_other/char/volatile_ptr.cc:
        Check result matches non-volatile pointer.

2021-10-05  Jonathan Wakely  <jwakely@redhat.com>

        PR c++/102535
        * testsuite/20_util/is_trivially_constructible/value.cc: Adjust
        expected value for C++20.

2021-10-05  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/std_function.h (_Any_data::_M_access): Add
        noexcept.
        (_Function_base::_Base_manager::_M_get_pointer): Likewise.
        (_Function_base::_Base_manager::_M_not_empty_function):
        Likewise.

2021-10-05  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/ostream (operator<<(const volatile void*)):
        Add new overload, as per P1147R1.
        * testsuite/27_io/basic_ostream/inserters_other/char/volatile_ptr.cc:
        New test.

2021-10-05  Jonathan Wakely  <jwakely@redhat.com>

        * 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.

2021-10-04  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/forward_list.h (forward_list): Use non-deduced
        context for allocator parameter of allocator-extended copy and
        move constructors.
        * include/bits/stl_bvector.h (vector<bool>): Likewise.
        * include/bits/stl_deque.h (deque): Likewise.
        * include/bits/stl_list.h (list): Likewise.
        * include/bits/stl_map.h (map): Likewise.
        * include/bits/stl_multimap.h (multimap): Likewise.
        * include/bits/stl_multiset.h (multiset): Likewise.
        * include/bits/stl_set.h (set): Likewise.
        * include/bits/stl_vector.h (vector): Likewise.
        * include/bits/stl_queue.h (queue, priority_queue): Do not
        constrain Allocator template parameter of deduction guides that
        have a Container parameter.
        * include/bits/stl_stack.h (stack): Likewise.
        * include/debug/deque (__gnu_debug::deque): Use non-deduced
        context for allocator parameter of allocator-extended copy and
        move constructors.
        * include/debug/list (__gnu_debug::list): Likewise.
        * include/debug/map.h (__gnu_debug::map): Likewise.
        * include/debug/multimap.h (__gnu_debug::multimap): Likewise.
        * include/debug/multiset.h (__gnu_debug::multiset): Likewise.
        * include/debug/set.h (__gnu_debug::set): Likewise.
        * include/debug/vector (__gnu_debug::vector): Likewise.
        * testsuite/23_containers/deque/cons/deduction.cc: Test class
        template argument deduction with non-deduced allocator
        arguments.
        * testsuite/23_containers/forward_list/cons/deduction.cc:
        Likewise.
        * testsuite/23_containers/list/cons/deduction.cc: Likewise.
        * testsuite/23_containers/map/cons/deduction.cc: Likewise.
        * testsuite/23_containers/multimap/cons/deduction.cc: Likewise.
        * testsuite/23_containers/multiset/cons/deduction.cc: Likewise.
        * testsuite/23_containers/priority_queue/deduction.cc: Likewise.
        * testsuite/23_containers/queue/deduction.cc: Likewise.
        * testsuite/23_containers/set/cons/deduction.cc: Likewise.
        * testsuite/23_containers/stack/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.
        * testsuite/23_containers/vector/cons/deduction.cc: Likewise.

2021-10-04  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/variant (__detail::__variant::__as): Add missing
        noexcept to first overload.

2021-10-04  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/basic_string.h (basic_string(nullptr_t)): Define
        as deleted.
        (operator=(nullptr_t)): Likewise.
        * include/bits/cow_string.h (basic_string(nullptr_t)): Likewise.
        (operator=(nullptr_t)): Likewise.
        * include/std/string_view (basic_string_view(nullptr_t)):
        Likewise.
        * testsuite/21_strings/basic_string/cons/char/nullptr.cc: New test.
        * testsuite/21_strings/basic_string_view/cons/char/nonnull.cc:
        Change dg-warning to dg-error.
        * testsuite/21_strings/basic_string_view/cons/wchar_t/nonnull.cc:
        Likewise.

2021-10-02  Jonathan Wakely  <jwakely@redhat.com>

        * src/c++17/fs_ops.cc (create_directory): Fix typo in enum name.
        * src/filesystem/ops-common.h (__last_system_error): Add
        explicit cast to avoid narrowing conversion.
        (do_space): Fix type in function name.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/102100
        * include/Makefile.am (c++config.h): Define
        _GLIBCXX_VERBOSE_ASSERT based on configure output.
        * include/Makefile.in: Regenerate.
        * include/bits/c++config: Fix condition for verbose assertions.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/92546
        * include/bits/erase_if.h (__erase_nodes_if): Use __niter_base to
        unwrap debug iterators.
        * include/bits/refwrap.h: Do not error if included in C++03.
        * include/bits/stl_algo.h (__remove_if): Move to ...
        * include/bits/stl_algobase.h (__remove_if): ... here.
        * include/std/deque (erase, erase_if): Use __remove_if instead of
        remove and remove_if.
        * include/std/string (erase, erase_if): Likewise.
        * include/std/vector (erase, erase_if): Likewise.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/66742
        * include/bits/list.tcc (list::sort()): Use _Scratch_list
        objects for splicing and merging.
        (list::sort(StrictWeakOrdering)): Likewise.
        * include/bits/stl_list.h (__detail::_Scratch_list): New type.
        * src/c++98/list.cc (_List_node_base::_M_transfer): Add
        assertion for --enable-libstdcxx-debug library.
        * testsuite/23_containers/list/operations/66742.cc: New test.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100612
        * include/std/thread (__pmf_expects_stop_token): New variable
        template to detect a pointer to member function that needs a
        stop_token to be added to the arguments.
        (jthread::__S_create): Use __pmf_expects_stop_token.
        (jthread::__S_create_pmf): New function.
        * testsuite/30_threads/jthread/100612.cc: New test.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        * 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  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/stl_queue.h (priority_queue): Add
        allocator-extended overloads for constructors taking iterator.
        * testsuite/23_containers/priority_queue/lwg3506.cc: New test.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/stl_queue.h (priority_queue): Construct sequence
        from iterators when no sequence argument is present (LWG 3529).
        * testsuite/23_containers/priority_queue/lwg3529.cc: New test.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/stl_queue.h (priority_queue): Constrain
        constructors with InputIterator parameters (LWG 3522).
        * testsuite/23_containers/priority_queue/lwg3522.cc: New test.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/ranges_base.h (ranges::distance): Split overload
        into two (LWG 3392).
        * testsuite/24_iterators/range_operations/lwg3392.cc: New test.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/30_threads/thread/cons/3.cc: Remove derivation from
        std::unary_function.
        * testsuite/30_threads/thread/cons/4.cc: Likewise.
        * testsuite/30_threads/thread/cons/5.cc: Likewise.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/ext/pb_ds/example/basic_multimap.cc: Remove
        unnecesary derivation from std::unary_function.
        * testsuite/ext/pb_ds/example/erase_if.cc: Likewise.
        * testsuite/ext/pb_ds/example/hash_illegal_resize.cc: Likewise.
        * testsuite/ext/pb_ds/example/hash_initial_size.cc: Likewise.
        * testsuite/ext/pb_ds/example/hash_load_set_change.cc: Likewise.
        * testsuite/ext/pb_ds/example/hash_mod.cc: Likewise.
        * testsuite/ext/pb_ds/example/hash_resize.cc: Likewise.
        * testsuite/ext/pb_ds/example/hash_shift_mask.cc: Likewise.
        * testsuite/ext/pb_ds/example/priority_queue_dijkstra.cc:
        Likewise.
        * testsuite/ext/pb_ds/example/ranged_hash.cc: Likewise.
        * testsuite/ext/pb_ds/example/store_hash.cc: Likewise.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        * src/c++11/functexcept.cc (__throw_out_of_range_fmt): Do not
        expand the format string for freestanding, or non-vebose, or if
        we're just going to abort anyway.
        * src/c++11/snprintf_lite.cc: Remove unused header and
        declaration.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/variant (__do_visit): Use variant_npos instead of
        literal -1 that requires a narrowing conversion.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99327
        * src/filesystem/ops-common.h (__unsupported): New function to
        return a suitable error code for missing functionality.
        (posix::off_t): New typedef.
        (posix::*): Set errno to ENOSYS instead of ENOTSUP for no-op
        fallback implementations.
        (do_copy_file): Replace uses of errc::not_supported.
        * src/c++17/fs_ops.cc (fs::copy, fs::copy_file, create_dir)
        (fs::create_directory, fs::create_directory_symlink)
        (fs::create_hard_link, fs::create_symlink, fs::current_path)
        (fs::equivalent, do_stat, fs::file_size, fs::hard_link_count)
        (fs::last_write_time, fs::permissions, fs::read_symlink):
        Replace uses of errc::not_supported.
        (fs::resize_file): Qualify off_t.
        * src/filesystem/ops.cc (fs::copy, fs::copy_file, create_dir)
        (fs::create_directory, fs::create_directory_symlink)
        (fs::create_hard_link, fs::create_symlink, fs::current_path)
        (fs::equivalent, do_stat, fs::file_size, fs::last_write_time)
        (fs::permissions, fs::read_symlink, fs::system_complete):
        Replace uses of errc::not_supported.
        (fs::resize_file): Qualify off_t and enable unconditionally.
        * testsuite/19_diagnostics/system_error/cons-1.cc: Likewise.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        * src/filesystem/ops-common.h (last_error): New helper function.
        (filesystem::do_space): Use last_error().
        * src/c++17/fs_ops.cc (fs::absolute, fs::create_hard_link)
        (fs::equivalent, fs::remove, fs::temp_directory_path): Use
        last_error().
        * src/filesystem/ops.cc (fs::create_hard_link)
        (fs::remove, fs::temp_directory_path): Likewise.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/type_traits (__conditional): New class template
        for internal uses of std::conditional.
        (__conditional_t): New alias template to replace conditional_t.
        (__and_, __or_, __result_of_memfun, __result_of_memobj): Use
        __conditional_t instead of conditional::type.
        * include/bits/atomic_base.h (__atomic_impl::_Diff): Likewise.
        * include/bits/hashtable.h (_Hashtable): Likewise.
        * include/bits/hashtable_policy.h (_Node_iterator, _Insert_base)
        (_Local_iterator): Likewise. Replace typedefs with
        using-declarations.
        * include/bits/move.h (move_if_noexcept): Use __conditional_t.
        * include/bits/parse_numbers.h (_Select_int_base): Likewise.
        * include/bits/ptr_traits.h (__make_not_void): Likewise.
        * include/bits/ranges_algobase.h (__copy_or_move_backward)
        (__copy_or_move): Likewise.
        * include/bits/ranges_base.h (borrowed_iterator_t): Likewise.
        * include/bits/ranges_util.h (borrowed_subrange_t): Likewise.
        * include/bits/regex_compiler.h (_BracketMatcher): Use
        __conditional_t. Replace typedefs with using-declarations.
        * include/bits/shared_ptr_base.h (__shared_count): Use
        __conditional_t.
        * include/bits/stl_algobase.h (__copy_move, __copy_move_backward):
        Likewise.
        * include/bits/stl_iterator.h (__detail::__clamp_iter_cat)
        (reverse_iterator::iterator_concept)
        (__make_move_if_noexcept_iterator)
        (iterator_traits<common_iterator<_It, _Sent>>)
        (iterator_traits<counted_iterator<_It>>): Likewise.
        * include/bits/stl_pair.h (_PCC, pair::operator=): Likewise.
        * include/bits/stl_tree.h (_Rb_tree::insert_return_type)
        (_Rb_tree::_M_clone_node): Likewise.
        * include/bits/unique_ptr.h (unique_ptr(unique_ptr<U,E>&&)):
        Likewise.
        * include/bits/uses_allocator.h (__uses_alloc): Likewise.
        (__is_uses_allocator_predicate): Likewise.
        * include/debug/functions.h (__foreign_iterator_aux2): Likewise.
        * include/experimental/any (any::_Manager, __any_caster):
        Likewise.
        * include/experimental/executor (async_completion): Likewise.
        * include/experimental/functional (__boyer_moore_base_t):
        Likewise.
        * include/std/any (any::_Manager): Likewise.
        * include/std/functional (__boyer_moore_base_t): Likewise.
        * include/std/ranges (borrowed_iterator_t)
        (borrowed_subrange_t, __detail::__maybe_present_t)
        (__detail::__maybe_const_t, split_view): Likewise.
        * include/std/tuple (__empty_not_final, tuple::operator=):
        Likewise.
        * include/std/variant (__detail::__variant::__get_t): Likewise.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/78113
        * include/std/variant (__do_visit): Use a switch when we have a
        single variant with a small number of alternatives.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        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  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/stl_iterator.h (__normal_iterator): Simplify
        converting constructor and do not require _Container::pointer.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/cow_string.h [_GLIBCXX_FULLY_DYNAMIC_STRING]
        (basic_string(basic_string&&)): Add noexcept and avoid
        allocation, by sharing rep with the rvalue string.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/stl_iterator.h (common_iterator::__arrow_proxy)
        (common_iterator::__postfix_proxy): Add noexcept.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/94418
        * include/bits/stl_iterator.h (reverse_iterator): Use
        conditional noexcept on constructors and assignment operators.
        * testsuite/24_iterators/reverse_iterator/noexcept.cc: New test.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100153
        * include/bits/vector.tcc (vector<bool>::_M_shrink_to_fit()):
        When size() is zero just deallocate and reset.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/96733
        * include/bits/stl_algo.h (clamp): Use std::min and std::max.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/regex.h (basic_regex::multiline): Define for
        non-strict C++11 and C++14 modes.
        * include/bits/regex_constants.h (regex_constants::multiline):
        Add _GLIBCXX_RESOLVE_LIB_DEFECTS comment.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/25_algorithms/is_permutation/2.cc: Include <iterator>.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/stream_iterator.h (istream_iterator): Add
        noexcept to constructors and non-throwing member functions and
        friend functions.
        (ostream_iterator): Likewise.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/boost_concept_check.h (_Is_vector_bool_iterator):
        New trait to identify vector<bool> iterators, including debug
        ones.
        (_ForwardIteratorReferenceConcept): Add default template
        argument using _Is_vector_bool_iterator and use it in partial
        specialization for the vector<bool> cases.
        (_Mutable_ForwardIteratorReferenceConcept): Likewise.
        * testsuite/24_iterators/operations/prev_neg.cc: Adjust dg-error
        line number.

2021-10-01  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/list.tcc (list::merge): Remove call to size() and
        try-catch block. Use _Finalize_merge instead.
        * include/bits/stl_list.h (list::_Finalize_merge): New
        scope guard type to update _M_size members after a merge.

2021-09-30  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/regex.h (basic_regex::multiline): Fix #if
        condition.

2021-09-29  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/regex.h (basic_regex::multiline): Define constant
        for C++17.
        * include/bits/regex_constants.h (regex_constants::multiline):
        Define constant for C++17.
        (regex_constants::__multiline): Define duplicate constant for
        internal use in C++11 and C++14.
        * include/bits/regex_executor.h (_Executor::_M_match_multiline()):
        New member function.
        (_Executor::_M_is_line_terminator(_CharT)): New member function.
        (_Executor::_M_at_begin(), _Executor::_M_at_end()): Use new
        member functions to support multiline matches.
        * testsuite/28_regex/algorithms/regex_match/multiline.cc: New test.

2021-09-29  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/regex_compiler.h (_Compiler::_S_validate): New
        function.
        * include/bits/regex_compiler.tcc (_Compiler::_Compiler): Use
        _S_validate to check flags.
        * include/bits/regex_error.h (_S_grammar): New error code for
        internal use.
        * testsuite/28_regex/basic_regex/ctors/grammar.cc: New test.

2021-09-29  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/84110
        * include/bits/regex_error.h (regex_constants::_S_null): New
        error code for internal use.
        * include/bits/regex_scanner.tcc (_Scanner::_M_scan_normal()):
        Check for null character.
        * testsuite/28_regex/basic_regex/84110.cc: New test.

2021-09-29  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/regex.h (__detail::__is_contiguous_iter): Move
        here from <bits/regex_compiler.h>.
        (basic_regex::_M_compile): New function to compile an NFA from
        a regular expression string.
        (basic_regex::basic_regex): Use _M_compile instead of delegating
        to other constructors.
        (basic_regex::operator=(const basic_regex&)): Define as
        defaulted.
        (basic_regex::operator=(initializer_list<C>)): Use _M_compile.
        (basic_regex::assign(const basic_regex&)): Use copy assignment.
        (basic_regex::assign(basic_regex&&)): Use move assignment.
        (basic_regex::assign(const C*, flag_type)): Use _M_compile
        instead of constructing a temporary string.
        (basic_regex::assign(const C*, size_t, flag_type)): Likewise.
        (basic_regex::assign(const basic_string<C,T,A>&, flag_type)):
        Use _M_compile instead of constructing a temporary basic_regex.
        (basic_regex::assign(InputIter, InputIter, flag_type)): Avoid
        constructing a temporary string for contiguous iterators of the
        right value type.
        * include/bits/regex_compiler.h (__is_contiguous_iter): Move to
        <bits/regex.h>.
        (__enable_if_contiguous_iter, __disable_if_contiguous_iter)
        (__compile_nfa): Remove.
        * testsuite/28_regex/basic_regex/assign/exception_safety.cc: New
        test.
        * testsuite/28_regex/basic_regex/ctors/char/other.cc: New test.

2021-09-28  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/atomic_timed_wait.h (__platform_wait_until_impl):
        Return false for ETIMEDOUT and true otherwise.

2021-09-28  François Dumont  <fdumont@gcc.gnu.org>

        * testsuite/20_util/default_delete/48631_neg.cc: Adapt dg-prune-output message
        to also match message with '__8' in it.

2021-09-28  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/regex_automaton.h (_NFA_base::_SizeT): Remove.
        * include/bits/regex_compiler.h (_Compiler::_IterT): Remove.
        * include/bits/regex_compiler.tcc: Likewise.
        * include/bits/regex_scanner.h (_Scanner::_IterT): Remove.
        * include/bits/regex_scanner.tcc: Likewise.

2021-09-28  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/regex_compiler.tcc: Add line break in empty while
        statement.
        * include/bits/regex_executor.tcc: Avoid unused parameter
        warning.

2021-09-28  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/regex.h (basic_regex, swap): Add noexcept to
        non-throwing functions.
        * include/bits/regex_automaton.h (_State_base, _State)
        (_NFA_base): Likewise.
        * include/bits/regex_compiler.h (_Compiler): Likewise.
        * include/bits/regex_error.h (regex_error::code()): Likewise.
        * include/bits/regex_scanner.h (_Scanner): Likewise.

2021-09-28  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/atomic_wait.h (_GLIBCXX_HAVE_PLATFORM_WAIT):
        Define before first attempt to check it.

2021-09-28  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/23_containers/priority_queue/requirements/explicit_instantiation/1.cc:
        Do not check non-default constructible sequences when
        _GLIBCXX_CONCEPT_CHECKS is defined.
        * testsuite/23_containers/priority_queue/requirements/explicit_instantiation/1_c++98.cc:
        Likewise.
        * testsuite/23_containers/queue/requirements/explicit_instantiation/1.cc:
        Likewise.
        * testsuite/23_containers/queue/requirements/explicit_instantiation/1_c++98.cc:
        Likewise.
        * testsuite/23_containers/stack/requirements/explicit_instantiation/1.cc:
        Likewise.
        * testsuite/23_containers/stack/requirements/explicit_instantiation/1_c++98.cc:
        Likewise.

2021-09-28  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/23_containers/deque/requirements/explicit_instantiation/3.cc:
        Do not test implicit allocator rebinding when _GLIBCXX_CONCEPT_CHECKS
        is defined.
        * testsuite/23_containers/forward_list/requirements/explicit_instantiation/3.cc:
        Likewise.
        * testsuite/23_containers/list/requirements/explicit_instantiation/3.cc:
        Likewise.
        * testsuite/23_containers/list/requirements/explicit_instantiation/5.cc:
        Likewise.
        * testsuite/23_containers/map/requirements/explicit_instantiation/3.cc:
        Likewise.
        * testsuite/23_containers/map/requirements/explicit_instantiation/5.cc:
        Likewise.
        * testsuite/23_containers/multimap/requirements/explicit_instantiation/3.cc:
        Likewise.
        * testsuite/23_containers/multimap/requirements/explicit_instantiation/5.cc:
        Likewise.
        * testsuite/23_containers/multiset/requirements/explicit_instantiation/3.cc:
        Likewise.
        * testsuite/23_containers/multiset/requirements/explicit_instantiation/5.cc:
        Likewise.
        * testsuite/23_containers/set/requirements/explicit_instantiation/3.cc:
        Likewise.
        * testsuite/23_containers/set/requirements/explicit_instantiation/5.cc:
        Likewise.
        * testsuite/23_containers/unordered_map/requirements/explicit_instantiation/3.cc:
        Likewise.
        * testsuite/23_containers/unordered_multimap/requirements/explicit_instantiation/3.cc:
        Likewise.
        * testsuite/23_containers/unordered_multiset/requirements/explicit_instantiation/3.cc:
        Likewise.
        * testsuite/23_containers/unordered_set/requirements/explicit_instantiation/3.cc:
        Likewise.
        * testsuite/23_containers/vector/ext_pointer/explicit_instantiation/3.cc:
        Likewise.
        * testsuite/23_containers/vector/requirements/explicit_instantiation/3.cc:
        Likewise.

2021-09-28  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/boost_concept_check.h (_ForwardIteratorConcept)
        (_BidirectionalIteratorConcept, _RandomAccessIteratorConcept):
        Check result types of iterator operations.
        (_Mutable_ForwardIteratorConcept): Check that iterator's
        reference type is a reference to its value type.
        (_Mutable_BidirectionalIteratorConcept): Do not require the
        value type to be assignable.
        (_Mutable_RandomAccessIteratorConcept): Likewise.
        * testsuite/24_iterators/operations/prev_neg.cc: Adjust dg-error
        line number.

2021-09-28  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/25_algorithms/copy/34595.cc: Add missing operation
        for type used as an iterator.
        * testsuite/25_algorithms/unique_copy/check_type.cc: Likewise.

2021-09-28  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/20_util/is_nothrow_swappable/value.h: Use custom
        comparison function for priority_queue of type with no
        relational operators.
        * testsuite/20_util/is_swappable/value.h: Likewise.
        * testsuite/24_iterators/output/concept.cc: Add operator< to
        type used in set.

2021-09-28  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/boost_concept_check.h (_OutputIteratorConcept):
        Use a function to preserve value category of the type.
        * include/bits/stl_algobase.h (copy, move, fill_n): Use a
        reference as the second argument for _OutputIteratorConcept.
        (copy_backward, move_backward): Use _OutputIteratorConcept
        instead of _ConvertibleConcept.

2021-09-28  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/stl_iterator.h (pointer_traits): Define partial
        specialization for __normal_iterator.
        * testsuite/24_iterators/normal_iterator/to_address.cc: New test.

2021-09-28  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/move.h (forward(remove_reference_t<T>&&)):
        Improve text of static_assert.
        * testsuite/20_util/forward/c_neg.cc: Adjust dg-error.
        * testsuite/20_util/forward/f_neg.cc: Likewise.

2021-09-28  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/102499
        * include/bits/fs_path.h (path::begin, path::end): Add noexcept
        to declarations, to match definitions.

2021-09-24  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/range_access.h (cbegin, cend): Remove redundant
        'inline' specifier.

2021-09-23  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/20_util/specialized_algorithms/memory_management_tools/destroy_neg.cc:
        Remove dg-error lines for C++20-only errors.

2021-09-23  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/19_diagnostics/headers/system_error/93151.cc:
        Disable PCH.

2021-09-23  Jonathan Wakely  <jwakely@redhat.com>

        * src/c++11/system_error.cc (system_error_category) [_WIN32]:
        Map Windows error codes to generic POSIX error numbers. Use
        FormatMessage instead of strerror.
        * testsuite/19_diagnostics/error_category/system_category.cc:
        Adjust for new behaviour on Windows.

2021-09-23  Jonathan Wakely  <jwakely@redhat.com>

        * src/c++11/system_error.cc (generic_error_category): Define
        class and virtual functions as 'final'.
        (generic_error_category::equivalent(int, const error_condition&)):
        Override.
        (system_error_category): Define class and virtual functions as
        'final'.
        (system_error_category::equivalent(int, const error_condition&)):
        Override.
        (generic_category_instance, system_category_instance): Use
        constinit union to make the objects immortal.

2021-09-23  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/102425
        * src/c++11/system_error.cc
        (system_error_category::default_error_condition): Add 0 to
        switch.
        * testsuite/19_diagnostics/error_category/102425.cc: New test.

2021-09-17  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/fs_path.h (path::iterator): Add noexcept to all
        member functions and friend functions.
        (distance): Add noexcept.
        (advance): Add noexcept and inline.
        * include/experimental/bits/fs_path.h (path::iterator):
        Add noexcept to all member functions.

2021-09-17  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/102270
        * include/std/tuple (_Tuple_impl): Add constexpr to constructor
        missed in previous patch.
        * testsuite/20_util/tuple/cons/102270.C: Moved to...
        * testsuite/20_util/tuple/cons/102270.cc: ...here.
        * testsuite/util/testsuite_allocator.h (SimpleAllocator): Add
        constexpr to constructor so it can be used for C++20 tests.

2021-09-17  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/26_numerics/valarray/dr630-3.C: Moved to...
        * testsuite/26_numerics/valarray/dr630-3.cc: ...here.
        * testsuite/27_io/basic_iostream/cons/16251.C: Moved to...
        * testsuite/27_io/basic_iostream/cons/16251.cc: ...here.

2021-09-16  Jonathan Wakely  <jwakely@redhat.com>

        * src/Makefile.am (stamp-debug): Add all Makefiles as
        prerequisites.
        * src/Makefile.in: Regenerate.

2021-09-16  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/ext/pb_ds/regression/tree_map_rand.cc: Increase
        timeout factor to 3.
        * testsuite/ext/pb_ds/regression/tree_set_rand.cc: Likewise.

2021-09-16  Jonathan Wakely  <jwakely@redhat.com>

        * doc/xml/manual/using.xml: Generalize to apply to more than
        just -std=c++11.
        * doc/html/manual/using_macros.html: Regenerate.

2021-09-16  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/optional (nullptr_t): Make constructor noexcept.

2021-09-16  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/fs_path.h (advance): Remove non-deducible
        template parameter.

2021-09-16  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/102270
        * include/std/tuple (_Head_base, _Tuple_impl): Add
        _GLIBCXX20_CONSTEXPR to allocator-extended constructors.
        (tuple<>::swap(tuple&)): Add _GLIBCXX20_CONSTEXPR.
        * testsuite/20_util/tuple/cons/102270.C: New test.

2021-09-16  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/102280
        * include/std/span (span(Range&&)): Add constraint to deduction
        guide.

2021-09-16  Jonathan Wakely  <jwakely@redhat.com>

        * src/c++98/Makefile.am: Use CXXCOMPILE not LTCXXCOMPILE.
        * src/c++98/Makefile.in: Regenerate.

2021-09-16  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/basic_string.h [_GLIBCXX_USE_CXX11_ABI]
        (to_string): Add noexcept if the type width is 32 bits or less.

2021-09-16  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/unique_ptr.h (__uniq_ptr_impl::_M_ptr)
        (__uniq_ptr_impl::_M_deleter): Add noexcept.

2021-09-16  Thomas Rodgers  <rodgert@twrodgers.com>

        PR libstdc++/101761
        * testsuite/29_atomics/atomic_ref/wait_notify.cc (test): Use
        va and vb as arguments to wait/notify, remove unused bb local.

2021-09-15  Hugo Beauzée-Luyssen  <hugo@beauzee.fr>

        * crossconfig.m4: Check for TLS support on mingw.
        * configure: Regenerate.

2021-09-13  Jason Merrill  <jason@redhat.com>

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

2021-09-10  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/experimental/net/internet/resolver/ops/lookup.cc:
        Fix invalid hostname to only match the .invalid TLD.

2021-09-02  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/atomic_base.h (__atomic_base<P*>::compare_exchange_weak):
        Add new functions.
        * include/std/atomic (atomic<T*>::compare_exchange_weak): Use
        it.

2021-09-02  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/atomic: Tweak whitespace.

2021-09-02  Jonathan Wakely  <jwakely@redhat.com>

        PR c++/102177
        * include/bits/atomic_base.h (__is_valid_cmpexch_failure_order):
        New function to check if a memory order is valid for the failure
        case of compare exchange operations.
        (__atomic_base<I>::compare_exchange_weak): Simplify assertions
        by using __is_valid_cmpexch_failure_order.
        (__atomic_base<I>::compare_exchange_strong): Likewise.
        (__atomic_base<P*>::compare_exchange_weak): Likewise.
        (__atomic_base<P*>::compare_exchange_strong): Likewise.
        (__atomic_impl::compare_exchange_weak): Add assertion.
        (__atomic_impl::compare_exchange_strong): Likewise.
        * include/std/atomic (atomic::compare_exchange_weak): Likewise.
        (atomic::compare_exchange_strong): Likewise.

2021-09-02  Jonathan Wakely  <jwakely@redhat.com>

        * 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.

2021-08-31  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/98421
        * include/std/span (span(Iter, size_type), span(Iter, Iter)):
        Add valid range checks.
        * testsuite/23_containers/span/cons_1_assert_neg.cc: New test.
        * testsuite/23_containers/span/cons_2_assert_neg.cc: New test.

2021-08-31  Jonathan Wakely  <jwakely@redhat.com>

        * configure.ac: Fix checks for F_GETFL, F_SETFL and O_NONBLOCK.
        * configure: Regenerate.

2021-08-31  Jonathan Wakely  <jwakely@redhat.com>

        * src/c++11/system_error.cc (error_category::~error_category()):
        Remove noexcept-specifier.
        (system_error::~system_error()): Likewise.
        * testsuite/19_diagnostics/error_category/noexcept.cc: New test.
        * testsuite/19_diagnostics/system_error/noexcept.cc: New test.

2021-08-31  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/102074
        * include/bits/atomic_timed_wait.h (__timed_waiter_pool)
        [!_GLIBCXX_HAVE_PLATFORM_TIMED_WAIT]: Add missing return.

2021-08-31  Jonathan Wakely  <jwakely@redhat.com>

        * include/experimental/internet (__make_resolver_error_code):
        Handle EAI_SYSTEM errors.
        (basic_resolver_results): Use __make_resolver_error_code. Use
        Glibc NI_MAXHOST and NI_MAXSERV values for buffer sizes.

2021-08-31  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/experimental/net/internet/resolver/ops/lookup.cc:
        Try other service if "http" fails.

2021-08-31  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/17_intro/names.cc: Undefine some more names used
        by Solaris system headers.

2021-08-30  Jason Merrill  <jason@redhat.com>

        PR c++/96286
        * testsuite/30_threads/promise/requirements/lwg3466.cc:
        Remove dg-prune-outputs.

2021-08-28  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/alloc_traits.h (allocator_traits): Add explicit
        specialization for allocator<void>. Improve doxygen comments.
        * include/bits/allocator.h (allocator<void>): Restore for the
        versioned namespace.
        (allocator<void>::construct, allocator<void>::destroy): Remove.
        * include/ext/extptr_allocator.h (_Extptr_allocator<void>):
        Add default constructor and converting constructor.

2021-08-28  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/stl_uninitialized.h: Fix typo in comment.

2021-08-28  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99876
        * src/c++17/fs_ops.cc (fs::absolute): Call non-throwing form,
        to avoid unnecessary current_path() call.

2021-08-28  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/std_function.h (function::function(F&&)): Give
        name to defaulted template parameter, to improve diagnostics.
        Use markdown for more doxygen comments.

2021-08-26  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/std_function.h (function): Adjust doxygen
        comments.
        * include/bits/unique_ptr.h (make_unique_for_overwrite):
        Change parameter name to match doxygen comment.

2021-08-26  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/std_function.h (_function_base::_Base_manager):
        Replace _M_init_functor with a function template using a
        forwarding reference, and a pair of _M_create function
        templates. Reuse _M_create for the clone operation.
        (function::_Decay_t): New alias template.
        (function::_Callable): Simplify by using _Decay.
        (function::function(F)): Change parameter to forwarding
        reference, as per LWG 2447. Add noexcept-specifier. Simplify
        constraints.
        (function::operator=(F&&)): Add noexcept-specifier.
        * testsuite/20_util/function/cons/lwg2774.cc: New test.
        * testsuite/20_util/function/cons/noexcept.cc: New test.

2021-08-26  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/std_function.h (function::function(F)): Add
        static assertions to check constructibility requirements.

2021-08-26  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100285
        * configure.ac: Check for O_NONBLOCK.
        * configure: Regenerate.
        * include/experimental/internet: Include <ws2tcpip.h> for
        Windows.  Use preprocessor conditions around more constants.
        * include/experimental/socket: Use preprocessor conditions
        around more constants.
        * testsuite/experimental/net/internet/resolver/base.cc: Only use
        constants when the corresponding C macro is defined.
        * testsuite/experimental/net/socket/basic_socket.cc: Likewise.
        * testsuite/experimental/net/socket/socket_base.cc: Likewise.
        Make preprocessor checks more fine-grained.

2021-08-25  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/17_intro/names.cc: Check 'sz'.

2021-08-25  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/17_intro/names.cc: Adjust for Windows.

2021-08-25  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/valarray: Uglify 'func' parameters.
        * testsuite/17_intro/names.cc: Add 'func' to checks.

2021-08-25  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/102064
        * include/bits/stl_uninitialized.h (_GLIBCXX_USE_ASSIGN_FOR_INIT):
        Define macro to check conditions for optimizing trivial cases.
        (__check_constructible): New function to do static assert.
        (uninitialized_copy, uninitialized_fill, uninitialized_fill_n):
        Use new macro.
        * testsuite/20_util/specialized_algorithms/uninitialized_copy/1.cc:
        Adjust dg-error pattern.
        * testsuite/23_containers/vector/cons/89164.cc: Likewise. Add
        C++17-specific checks from 89164_c++17.cc.
        * testsuite/23_containers/vector/cons/89164_c++17.cc: Removed.
        * testsuite/20_util/specialized_algorithms/uninitialized_copy/102064.cc:
        New test.
        * testsuite/20_util/specialized_algorithms/uninitialized_copy_n/102064.cc:
        New test.
        * testsuite/20_util/specialized_algorithms/uninitialized_fill/102064.cc:
        New test.
        * testsuite/20_util/specialized_algorithms/uninitialized_fill_n/102064.cc:
        New test.

2021-08-25  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/102048
        * include/ext/rope (rope::erase(size_type)): Remove broken
        function.

2021-08-24  Jonathan Wakely  <jwakely@redhat.com>

        * doc/xml/manual/status_cxx2020.xml: Update table.
        * doc/html/manual/status.html: Regenerate.

2021-08-24  Jonathan Wakely  <jwakely@redhat.com>

        * 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  Jonathan Wakely  <jwakely@redhat.com>

        * src/c++11/cxx11-shim_facets.cc: Fix mismatched class-key in
        explicit instantiation definitions.

2021-08-23  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/ranges (basic_istream_view): Add default template
        argument.
        * testsuite/std/ranges/istream_view.cc: Check it.

2021-08-23  Jonathan Wakely  <jwakely@redhat.com>

        * libsupc++/dyncast.cc (__dynamic_cast): Add __builtin_expect to
        precondition check.

2021-08-23  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/90787
        * testsuite/util/testsuite_fs.h (permissions_are_testable):
        Define as inline.

2021-08-20  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/90787
        * testsuite/27_io/filesystem/iterators/directory_iterator.cc:
        Use new __gnu_test::permissions_are_testable() function.
        * testsuite/27_io/filesystem/iterators/recursive_directory_iterator.cc:
        Likewise.
        * testsuite/27_io/filesystem/operations/exists.cc: Likewise.
        * testsuite/27_io/filesystem/operations/is_empty.cc: Likewise.
        * testsuite/27_io/filesystem/operations/remove.cc: Likewise.
        * testsuite/27_io/filesystem/operations/remove_all.cc: Likewise.
        * testsuite/27_io/filesystem/operations/status.cc: Likewise.
        * testsuite/27_io/filesystem/operations/symlink_status.cc:
        Likewise.
        * testsuite/27_io/filesystem/operations/temp_directory_path.cc:
        Likewise.
        * testsuite/experimental/filesystem/iterators/directory_iterator.cc:
        Likewise.
        * testsuite/experimental/filesystem/iterators/recursive_directory_iterator.cc:
        Likewise.
        * testsuite/experimental/filesystem/operations/exists.cc:
        Likewise.
        * testsuite/experimental/filesystem/operations/is_empty.cc:
        Likewise.
        * testsuite/experimental/filesystem/operations/remove.cc:
        Likewise.
        * testsuite/experimental/filesystem/operations/remove_all.cc:
        Likewise.
        * testsuite/experimental/filesystem/operations/temp_directory_path.cc:
        Likewise.
        * testsuite/util/testsuite_fs.h (__gnu_test::permissions_are_testable):
        New function to guess whether testing permissions will work.

2021-08-19  Jonathan Wakely  <jwakely@redhat.com>

        * doc/xml/manual/status_cxx2020.xml: Move row  earlier in table.
        * doc/html/manual/status.html: Regenerate.

2021-08-19  Jonathan Wakely  <jwakely@redhat.com>

        * doc/doxygen/user.cfg.in: Update to Doxygen 1.9.2

2021-08-19  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101965
        * include/std/charconv (__to_chars_i): Remove redundant check.

2021-08-19  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101960
        * include/std/tuple (_Tuple_impl(_Tuple_impl&&)): Use base
        class' move constructor. Define as defaulted for versioned
        namespace.
        * testsuite/20_util/tuple/cons/101960.cc: New test.

2021-08-19  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100139
        * doc/xml/manual/status_cxx2020.xml: Add P1739R4 to status table.
        * doc/html/manual/status.html: Regenerate.

2021-08-19  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/shared_ptr.h: Add @since and @headerfile tags.
        * include/bits/unique_ptr.h: Add @headerfile tags.

2021-08-19  Jonathan Wakely  <jwakely@redhat.com>

        * src/filesystem/ops-common.h (filesystem::file_time): Improve
        overflow check by using system_clock::duration::max().

2021-08-19  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/stl_tree.h: Tweak whitespace.

2021-08-18  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/unique_ptr.h (default_delete): Add @since tag.
        (unique_ptr, unique_ptr<T[]>): Likewise. Improve @brief.
        (make_unique, make_unique_for_overwrite): Likewise. Add @tparam,
        @param, and @returns.
        (_MakeUniq): Move to __detail namespace. Add alias template
        helpers.

2021-08-18  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/stl_function.h: Improve doxygen comments.

2021-08-18  Jonathan Wakely  <jwakely@redhat.com>

        * doc/doxygen/user.cfg.in (PREDEFINED): Enable doxygen
        processing for C++20 components and components that depend on
        compiler features.
        * include/bits/stl_algo.h (random_shuffle): Use @deprecated.
        * include/std/type_traits: Improve doxygen comments for C++20
        traits.

2021-08-18  Jonathan Wakely  <jwakely@redhat.com>

        * include/ext/type_traits.h (__promote_2, __promote_3)
        (__promote_4): Redfine as alias templates using __promoted_t.
        * include/std/complex (__promote_2): Remove partial
        specializations for std::complex.

2021-08-18  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/stl_algo.h (min(initializer_list<T>))
        (min(initializer_list<T>, Compare)): Call __min_element directly to
        avoid redundant debug checks for valid ranges.
        (max(initializer_list<T>), max(initializer_list<T>, Compare)):
        Likewise, for __max_element.
        (minmax(initializer_list<T>), minmax(initializer_list<T>, Compare)):
        Likewise, for __minmax_element.

2021-08-18  Jonathan Wakely  <jwakely@redhat.com>

        * include/debug/deque (deque(size_type, const T&, const A&)):
        Prevent class template argument deduction and replace with a
        deduction guide.
        * include/debug/forward_list (forward_list(size_type, const T&, const A&)):
        Likewise.
        * include/debug/list (list(size_type, const T&, const A&)):
        Likewise.
        * include/debug/vector (vector(size_type, const T&, const A&)):
        Likewise.

2021-08-18  Jonathan Wakely  <jwakely@redhat.com>

        * python/libstdcxx/v6/printers.py (StdBitReferencePrinter): Use
        'std::vector<bool>::reference' as type name, not _Bit_reference.
        (build_libstdcxx_dictionary): Register printers for vector<bool>
        types in debug mode too.
        * testsuite/libstdc++-prettyprinters/simple.cc: Adjust expected
        output for invalid _Bit_reference. Use vector<bool>::reference
        instead of _Bit_reference.
        * testsuite/libstdc++-prettyprinters/simple11.cc: Likewise.

2021-08-17  Thomas Schwinge  <thomas@codesourcery.com>

        * testsuite/lib/libstdc++.exp: Avoid illegal argument to verbose,
        continued.

2021-08-17  Luc Michel  <lmichel@kalray.eu>
            Marc Poulhies  <mpoulhies@kalrayinc.com>

        * testsuite/lib/gdb-test.exp (gdb_version_check)
        (gdb_version_check_xmethods): Only check the GDB version for
        local native targets.

2021-08-17  Antony Polukhin  <antoshkka@gmail.com>
            Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/random.tcc (seed_seq::seed_seq): Reserve capacity
        if distance is O(1).
        * testsuite/26_numerics/random/pr60037-neg.cc: Adjust dg-error
        line number.

2021-08-17  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/26_numerics/random/seed_seq/cons/range.cc: Check
        construction from input iterators.

2021-08-17  Jonathan Wakely  <jwakely@redhat.com>

        * python/libstdcxx/v6/printers.py (StdErrorCatPrinter): Remove.

2021-08-17  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101923
        * include/bits/std_function.h (function(function&&)): Check for
        non-empty parameter before doing any work.

2021-08-17  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/cow_string.h (basic_string::contains): Do not
        define for -std=gnu++20.

2021-08-17  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/ranges_util.h (__not_same_as): Rename to
        __different_from.
        * include/std/ranges (__not_same_as): Likewise.

2021-08-17  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/utility (exchange): Add noexcept-specifier.
        * testsuite/20_util/exchange/noexcept.cc: New test.

2021-08-17  Jonathan Wakely  <jwakely@redhat.com>

        * python/libstdcxx/v6/printers.py (StdErrorCodePrinter): Define.
        (build_libstdcxx_dictionary): Register printer for
        std::error_code and std::error_condition.
        * testsuite/libstdc++-prettyprinters/cxx11.cc: Test it.

2021-08-16  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101937
        * src/c++11/debug.cc (PrintContext::_M_indent): Replace with a
        static data member.
        (print_word): Use qualified-id to access it.

2021-08-16  Jonathan Wakely  <jwakely@redhat.com>

        * python/Makefile.am [GLIBCXX_BUILD_DEBUG] (install-data-local):
        Install another copy of the GDB hook.
        * python/Makefile.in: Regenerate.

2021-08-12  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101870
        * include/c_global/cmath (hypot): Use __promoted_t.
        (lerp): Add new overload accepting any arithmetic types.
        * include/ext/type_traits.h (__promoted_t): New alias template.
        * testsuite/26_numerics/lerp.cc: Moved to...
        * testsuite/26_numerics/lerp/1.cc: ...here.
        * testsuite/26_numerics/lerp/constexpr.cc: New test.
        * testsuite/26_numerics/lerp/version.cc: New test.

2021-08-12  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/26_numerics/lerp.cc: Add header name to #error.
        * testsuite/26_numerics/midpoint/integral.cc: Likewise.
        * testsuite/26_numerics/midpoint/version.cc: New test.

2021-08-12  Jonathan Wakely  <jwakely@redhat.com>

        * include/experimental/random (experimental::randint): Add
        nodiscard attribute.

2021-08-12  Jonathan Wakely  <jwakely@redhat.com>

        * src/c++98/locale_init.cc: Require C++11.
        * src/c++98/localename.cc: Likewise.
        * src/c++98/misc-inst.cc: Require C++98.

2021-08-11  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101866
        * testsuite/experimental/random/randint.cc: Loop and retry if
        reseed() produces the same sequence.

2021-08-11  Jonathan Wakely  <jwakely@redhat.com>

        * 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.

2021-08-09  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/regex.h (basic_regex::transform_primary): Use
        _GLIBCXX_STD_C::vector for local variable.
        * include/bits/regex.tcc (__regex_algo_impl): Use reference to
        _GLIBCXX_STD_C::vector base class of match_results.
        * include/bits/regex_automaton.tcc (_StateSeq:_M_clone): Use
        _GLIBCXX_STD_C::map and _GLIBCXX_STD_C::deque for local
        variables.
        * include/bits/regex_compiler.h (_BracketMatcher): Use
        _GLIBCXX_STD_C::vector for data members.
        * include/bits/regex_executor.h (_Executor): Likewise.
        * include/std/regex [_GLIBCXX_DEBUG]: Include <debug/vector>.

2021-08-09  François Dumont  <fdumont@gcc.gnu.org>

        * include/debug/safe_container.h
        (_Safe_container(_Safe_container&&, const _Alloc&, std::true_type)): New.
        (_Safe_container(_Safe_container&&, const _Alloc&, std::false_type)): New.
        (_Safe_container(_Safe_container&&, const _Alloc&)): Use latters.

2021-08-09  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/23_containers/unordered_map/cons/default.cc: Add
        equality comparison operators to allocator.
        * testsuite/23_containers/unordered_set/cons/default.cc:
        Likewise.

2021-08-08  François Dumont  <fdumont@gcc.gnu.org>

        * testsuite/25_algorithms/copy/debug/constexpr_neg.cc: Replace 'failed_assertion'
        dg-prune-output reason with 'builtin_unreachable'.
        * testsuite/25_algorithms/copy_backward/debug/constexpr_neg.cc: Likewise.
        * testsuite/25_algorithms/equal/debug/constexpr_neg.cc: Likewise.
        * testsuite/25_algorithms/lower_bound/debug/constexpr_partitioned_neg.cc: Likewise.
        * testsuite/25_algorithms/lower_bound/debug/constexpr_partitioned_pred_neg.cc: Likewise.
        * testsuite/25_algorithms/lower_bound/debug/constexpr_valid_range_neg.cc: Likewise.
        * testsuite/25_algorithms/upper_bound/debug/constexpr_partitioned_neg.cc: Likewise.
        * testsuite/25_algorithms/upper_bound/debug/constexpr_partitioned_pred_neg.cc: Likewise.
        * testsuite/25_algorithms/upper_bound/debug/constexpr_valid_range_neg.cc: Likewise.

2021-08-08  Hans-Peter Nilsson  <hp@bitrange.com>

        * testsuite/std/ranges/iota/max_size_type.cc: Set
        dg-timeout-factor to 4.

2021-08-06  Jonathan Wakely  <jwakely@redhat.com>

        * libsupc++/compare (compare_three_way, strong_order)
        (weak_order, partial_order, compare_strong_order_fallback)
        (compare_weak_order_fallback, compare_partial_order_fallback):
        Move nodiscard attributes to correct location.

2021-08-05  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101782
        * include/bits/ranges_base.h (ranges::begin, ranges::end)
        (ranges::rbegin, ranges::rend, ranges::size, ranges::ssize)
        (ranges::empty, ranges::data): Move attribute after the
        declarator-id instead of at the end of the declarator.
        * include/bits/stl_iterator.h (__gnu_cxx::__normal_iterator):
        Move attributes back to the start of the function declarator,
        but move the requires-clause to the end.
        (common_iterator): Move attribute after the declarator-id.
        * include/bits/stl_queue.h (queue): Remove ill-formed attributes
        from friend declaration that are not definitions.
        * include/std/ranges (views::all, views::filter)
        (views::transform, views::take, views::take_while,
        views::drop) (views::drop_while, views::join,
        views::lazy_split) (views::split, views::counted,
        views::common, views::reverse) (views::elements): Move
        attributes after the declarator-id.

2021-08-05  Jonathan Wakely  <jwakely@redhat.com>

        * libsupc++/compare (partial_ordering, weak_ordering)
        (strong_ordering, is_eq, is_neq, is_lt, is_lteq, is_gt, is_gteq)
        (compare_three_way, strong_order, weak_order, partial_order)
        (compare_strong_order_fallback, compare_weak_order_fallback)
        (compare_partial_order_fallback, __detail::__synth3way): Add
        nodiscard attribute.
        * testsuite/18_support/comparisons/categories/zero_neg.cc: Add
        -Wno-unused-result to options.

2021-08-05  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101782
        * include/bits/ranges_base.h (ranges::begin, ranges::end)
        (ranges::rbegin, ranges::rend, ranges::size, ranges::ssize)
        (ranges::empty, ranges::data): Move attribute to the end of
        the declarator.
        * include/bits/stl_iterator.h (__gnu_cxx::__normal_iterator)
        (common_iterator): Likewise for non-member operator functions.
        * include/std/ranges (views::all, views::filter)
        (views::transform, views::take, views::take_while, views::drop)
        (views::drop_while, views::join, views::lazy_split)
        (views::split, views::counted, views::common, views::reverse)
        (views::elements): Likewise.
        * testsuite/std/ranges/access/101782.cc: New test.

2021-08-04  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/forward_list.h: Add [[nodiscard]] to functions
        with no side-effects.
        * include/bits/stl_bvector.h: Likewise.
        * include/bits/stl_deque.h: Likewise.
        * include/bits/stl_list.h: Likewise.
        * include/bits/stl_queue.h: Likewise.
        * include/bits/stl_stack.h: Likewise.
        * include/bits/stl_vector.h: Likewise.
        * include/debug/deque: Likewise.
        * include/debug/forward_list: Likewise.
        * include/debug/list: Likewise.
        * include/debug/safe_iterator.h: Likewise.
        * include/debug/vector: Likewise.
        * include/std/array: Likewise.
        * testsuite/23_containers/array/creation/3_neg.cc: Use
        -Wno-unused-result.
        * testsuite/23_containers/array/debug/back1_neg.cc: Cast result
        to void.
        * testsuite/23_containers/array/debug/back2_neg.cc: Likewise.
        * testsuite/23_containers/array/debug/front1_neg.cc: Likewise.
        * testsuite/23_containers/array/debug/front2_neg.cc: Likewise.
        * testsuite/23_containers/array/debug/square_brackets_operator1_neg.cc:
        Likewise.
        * testsuite/23_containers/array/debug/square_brackets_operator2_neg.cc:
        Likewise.
        * testsuite/23_containers/array/tuple_interface/get_neg.cc:
        Adjust dg-error line numbers.
        * testsuite/23_containers/deque/cons/clear_allocator.cc: Cast
        result to void.
        * testsuite/23_containers/deque/debug/invalidation/4.cc:
        Likewise.
        * testsuite/23_containers/deque/types/1.cc: Use
        -Wno-unused-result.
        * testsuite/23_containers/list/types/1.cc: Cast result to void.
        * testsuite/23_containers/priority_queue/members/7161.cc:
        Likewise.
        * testsuite/23_containers/queue/members/7157.cc: Likewise.
        * testsuite/23_containers/vector/59829.cc: Likewise.
        * testsuite/23_containers/vector/ext_pointer/types/1.cc:
        Likewise.
        * testsuite/23_containers/vector/ext_pointer/types/2.cc:
        Likewise.
        * testsuite/23_containers/vector/types/1.cc: Use
        -Wno-unused-result.

2021-08-04  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/iterator_concepts.h (iter_move): Add
        [[nodiscard]].
        * include/bits/range_access.h (begin, end, cbegin, cend)
        (rbegin, rend, crbegin, crend, size, data, ssize): Likewise.
        * include/bits/ranges_base.h (ranges::begin, ranges::end)
        (ranges::cbegin, ranges::cend, ranges::rbegin, ranges::rend)
        (ranges::crbegin, ranges::crend, ranges::size, ranges::ssize)
        (ranges::empty, ranges::data, ranges::cdata): Likewise.
        * include/bits/stl_iterator.h (reverse_iterator, __normal_iterator)
        (back_insert_iterator, front_insert_iterator, insert_iterator)
        (move_iterator, move_sentinel, common_iterator)
        (counted_iterator): Likewise.
        * include/bits/stl_iterator_base_funcs.h (distance, next, prev):
        Likewise.
        * include/bits/stream_iterator.h (istream_iterator)
        (ostream_iterartor): Likewise.
        * include/bits/streambuf_iterator.h (istreambuf_iterator)
        (ostreambuf_iterator): Likewise.
        * include/std/ranges (views::single, views::iota, views::all)
        (views::filter, views::transform, views::take, views::take_while)
        (views::drop, views::drop_while, views::join, views::lazy_split)
        (views::split, views::counted, views::common, views::reverse)
        (views::elements): Likewise.
        * testsuite/20_util/rel_ops.cc: Use -Wno-unused-result.
        * testsuite/24_iterators/move_iterator/greedy_ops.cc: Likewise.
        * testsuite/24_iterators/normal_iterator/greedy_ops.cc:
        Likewise.
        * testsuite/24_iterators/reverse_iterator/2.cc: Likewise.
        * testsuite/24_iterators/reverse_iterator/greedy_ops.cc:
        Likewise.
        * testsuite/21_strings/basic_string/range_access/char/1.cc:
        Cast result to void.
        * testsuite/21_strings/basic_string/range_access/wchar_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/range_access/char/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/range_access/wchar_t/1.cc:
        Likewise.
        * testsuite/23_containers/array/range_access.cc: Likewise.
        * testsuite/23_containers/deque/range_access.cc: Likewise.
        * testsuite/23_containers/forward_list/range_access.cc:
        Likewise.
        * testsuite/23_containers/list/range_access.cc: Likewise.
        * testsuite/23_containers/map/range_access.cc: Likewise.
        * testsuite/23_containers/multimap/range_access.cc: Likewise.
        * testsuite/23_containers/multiset/range_access.cc: Likewise.
        * testsuite/23_containers/set/range_access.cc: Likewise.
        * testsuite/23_containers/unordered_map/range_access.cc:
        Likewise.
        * testsuite/23_containers/unordered_multimap/range_access.cc:
        Likewise.
        * testsuite/23_containers/unordered_multiset/range_access.cc:
        Likewise.
        * testsuite/23_containers/unordered_set/range_access.cc:
        Likewise.
        * testsuite/23_containers/vector/range_access.cc: Likewise.
        * testsuite/24_iterators/customization_points/iter_move.cc:
        Likewise.
        * testsuite/24_iterators/istream_iterator/sentinel.cc:
        Likewise.
        * testsuite/24_iterators/istreambuf_iterator/sentinel.cc:
        Likewise.
        * testsuite/24_iterators/move_iterator/dr2061.cc: Likewise.
        * testsuite/24_iterators/operations/prev_neg.cc: Likewise.
        * testsuite/24_iterators/ostreambuf_iterator/2.cc: Likewise.
        * testsuite/24_iterators/range_access/range_access.cc:
        Likewise.
        * testsuite/24_iterators/range_operations/100768.cc: Likewise.
        * testsuite/26_numerics/valarray/range_access2.cc: Likewise.
        * testsuite/28_regex/range_access.cc: Likewise.
        * testsuite/experimental/string_view/range_access/char/1.cc:
        Likewise.
        * testsuite/experimental/string_view/range_access/wchar_t/1.cc:
        Likewise.
        * testsuite/ext/vstring/range_access.cc: Likewise.
        * testsuite/std/ranges/adaptors/take.cc: Likewise.
        * testsuite/std/ranges/p2259.cc: Likewise.

2021-08-03  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/random.tcc (linear_congruential_engine): Do not
        define static constexpr members when they are implicitly inline.
        * include/std/ratio (ratio, __ratio_multiply, __ratio_divide)
        (__ratio_add, __ratio_subtract): Likewise.
        * include/std/type_traits (integral_constant): Likewise.
        * testsuite/26_numerics/random/pr60037-neg.cc: Adjust dg-error
        line number.

2021-08-03  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/util/testsuite_common_types.h: Replace uses of
        tr1::unordered_map and tr1::unordered_set with their C++11
        equivalents.
        * testsuite/29_atomics/atomic/cons/assign_neg.cc: Adjust
        dg-error line number.
        * testsuite/29_atomics/atomic/cons/copy_neg.cc: Likewise.
        * testsuite/29_atomics/atomic_integral/cons/assign_neg.cc:
        Likewise.
        * testsuite/29_atomics/atomic_integral/cons/copy_neg.cc:
        Likewise.
        * testsuite/29_atomics/atomic_integral/operators/bitwise_neg.cc:
        Likewise.
        * testsuite/29_atomics/atomic_integral/operators/decrement_neg.cc:
        Likewise.
        * testsuite/29_atomics/atomic_integral/operators/increment_neg.cc:
        Likewise.

2021-08-03  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/memory_resource (polymorphic_allocator::delete_object):
        Call destructor directly instead of using destroy.
        (allocator_traits<polymorphic_allocator<T>>): Define partial
        specialization.

2021-08-03  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/20_util/function_objects/binders/3113.cc: Remove
        trailing whitespace.
        * testsuite/20_util/shared_ptr/assign/auto_ptr.cc: Likewise.
        * testsuite/20_util/shared_ptr/assign/auto_ptr_neg.cc: Likewise.
        * testsuite/20_util/shared_ptr/assign/auto_ptr_rvalue.cc:
        Likewise.
        * testsuite/20_util/shared_ptr/creation/dr925.cc: Likewise.
        * testsuite/25_algorithms/headers/algorithm/synopsis.cc:
        Likewise.
        * testsuite/25_algorithms/random_shuffle/requirements/explicit_instantiation/2.cc:
        Likewise.
        * testsuite/25_algorithms/random_shuffle/requirements/explicit_instantiation/pod.cc:
        Likewise.

2021-08-03  Jonathan Wakely  <jwakely@redhat.com>

        * doc/xml/manual/evolution.xml: Document deprecation.
        * doc/html/*: Regenerate.
        * include/bits/c++config (_GLIBCXX14_DEPRECATED): Define.
        (_GLIBCXX14_DEPRECATED_SUGGEST): Define.
        * include/bits/stl_algo.h (random_shuffle): Deprecate for C++14
        and later.
        * testsuite/25_algorithms/headers/algorithm/synopsis.cc: Adjust
        for C++11 and C++14 changes to std::random_shuffle and
        std::shuffle.
        * testsuite/25_algorithms/random_shuffle/1.cc: Add options to
        use deprecated algorithms.
        * testsuite/25_algorithms/random_shuffle/59603.cc: Likewise.
        * testsuite/25_algorithms/random_shuffle/moveable.cc: Likewise.
        * testsuite/25_algorithms/random_shuffle/requirements/explicit_instantiation/2.cc:
        Likewise.
        * testsuite/25_algorithms/random_shuffle/requirements/explicit_instantiation/pod.cc:
        Likewise.

2021-08-03  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/23_containers/forward_list/operations/3.cc:
        Use lambda instead of std::bind2nd.
        * testsuite/20_util/function_objects/binders/3113.cc: Add
        options for testing deprecated features.
        * testsuite/20_util/pair/cons/99957.cc: Likewise.
        * testsuite/20_util/shared_ptr/assign/auto_ptr.cc: Likewise.
        * testsuite/20_util/shared_ptr/assign/auto_ptr_neg.cc: Likewise.
        * testsuite/20_util/shared_ptr/assign/auto_ptr_rvalue.cc:
        Likewise.
        * testsuite/20_util/shared_ptr/cons/43820_neg.cc: Likewise.
        * testsuite/20_util/shared_ptr/cons/auto_ptr.cc: Likewise.
        * testsuite/20_util/shared_ptr/cons/auto_ptr_neg.cc: Likewise.
        * testsuite/20_util/shared_ptr/creation/dr925.cc: Likewise.
        * testsuite/20_util/unique_ptr/cons/auto_ptr.cc: Likewise.
        * testsuite/20_util/unique_ptr/cons/auto_ptr_neg.cc: Likewise.
        * testsuite/ext/pb_ds/example/priority_queue_erase_if.cc:
        Likewise.
        * testsuite/ext/pb_ds/example/priority_queue_split_join.cc:
        Likewise.
        * testsuite/lib/dg-options.exp (dg_add_options_using-deprecated):
        New proc.

2021-08-03  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/regex_executor.h (_State_info): Replace
        unique_ptr<bool[]> with array of bool.
        * include/bits/regex_executor.tcc: Likewise.
        * include/bits/regex_scanner.tcc: Replace std::strchr with
        __builtin_strchr.
        * include/std/regex: Replace standard headers with smaller
        internal ones.
        * testsuite/28_regex/traits/char/lookup_classname.cc: Include
        <string.h> for strlen.
        * testsuite/28_regex/traits/char/lookup_collatename.cc:
        Likewise.

2021-08-03  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/locale_conv.h (__detail::_Scoped_ptr): Define new
        RAII class template.
        (wstring_convert, wbuffer_convert): Use __detail::_Scoped_ptr
        instead of unique_ptr.

2021-08-02  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/101599
        * include/bits/ranges_algo.h (__reverse_copy_fn::operator()):
        Add missing std::move in return statement.
        (__partition_copy_fn::operator()): Rename templtae parameter
        _O2 to _Out2.  Uglify function parameters out_true and out_false.
        * include/bits/ranges_algobase.h (__copy_or_move): Add missing
        std::move to recursive call that unwraps a __normal_iterator
        output iterator.
        * testsuite/25_algorithms/copy/constrained.cc (test06): New test.
        * testsuite/25_algorithms/move/constrained.cc (test05): New test.

2021-08-02  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/101589
        * include/std/ranges (lazy_split_view::_InnerIter::base): Make
        the const& overload unconstrained and return a const reference
        as per LWG 3533.  Make unconditionally noexcept.
        (elements_view::base): Revert accidental r12-569 change.
        (elements_view::_Iterator::base): Make the const& overload
        unconstrained and return a const reference as per LWG 3533.
        Make unconditionally noexcept.

2021-08-02  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/101483
        * include/std/ranges (join_view::_Iterator::_Iterator): Add
        missing std::move.

2021-08-02  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101709
        * src/filesystem/ops-common.h (get_temp_directory_from_env):
        Add error_code parameter.
        * src/c++17/fs_ops.cc (fs::temp_directory_path): Pass error_code
        argument to get_temp_directory_from_env and check it.
        * src/filesystem/ops.cc (fs::temp_directory_path): Likewise.

2021-08-02  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/20_util/tuple/comparison_operators/overloaded2.cc:
        Add dg-error for c++11_only target.

2021-07-30  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/65018
        * configure.ac: Check for secure_getenv.
        * config.h.in: Regenerate.
        * configure: Regenerate.
        * src/filesystem/ops-common.h (get_temp_directory_from_env): New
        helper function to obtain path from the environment.
        * src/c++17/fs_ops.cc (fs::temp_directory_path): Use new helper.
        * src/filesystem/ops.cc (fs::temp_directory_path): Likewise.
        * testsuite/27_io/filesystem/operations/temp_directory_path.cc:
        Print messages if test cannot be run.
        * testsuite/experimental/filesystem/operations/temp_directory_path.cc:
        Likewise. Fix incorrect condition. Use "TMP" to work with
        Windows as well as POSIX.

2021-07-29  Hans-Peter Nilsson  <hp@bitrange.com>

        * src/c++17/memory_resource.cc: Use __exchange instead
        of std::exchange.

2021-07-27  Jonathan Wakely  <jwakely@redhat.com>

        * include/experimental/optional (__throw_bad_optional_access):
        Replace GNU attribute with C++11 attribute.
        (optional::value, optional::value_or): Use if statements
        instead of conditional expressions.
        * include/std/optional (__throw_bad_optional_access)
        (optional::value, optional::value_or): Likewise.

2021-07-27  Marek Polacek  <polacek@redhat.com>

        DR 1512
        PR c++/99701
        * testsuite/20_util/tuple/comparison_operators/overloaded.cc:
        Move a line...
        * testsuite/20_util/tuple/comparison_operators/overloaded2.cc:
        ...here.  New test.

2021-07-27  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/cow_string.h: Consistently use tab for
        indentation.

2021-07-27  Jonathan Wakely  <jwakely@redhat.com>

        * include/Makefile.am: Add new header.
        * include/Makefile.in: Regenerate.
        * include/bits/basic_string.h [!_GLIBCXX_USE_CXX11_ABI]
        (basic_string): Move definition of Copy-on-Write string to
        new file.
        * include/bits/basic_string.tcc: Likewise.
        * include/bits/cow_string.h: New file.

2021-07-27  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/algorithm: Do not include <utility>.
        * include/std/functional: Likewise.
        * include/std/regex: Include <bits/stl_pair.h> instead of
        <utility>.
        * include/debug/map.h: Likewise.
        * include/debug/multimap.h: Likewise.
        * include/debug/multiset.h: Likewise.
        * include/debug/set.h: Likewise.
        * include/debug/vector: Likewise.
        * include/bits/fs_path.h: Likewise.
        * include/bits/unique_ptr.h: Do not include <utility>.
        * include/experimental/any: Likewise.
        * include/experimental/executor: Likewise.
        * include/experimental/memory: Likewise.
        * include/experimental/optional: Likewise.
        * include/experimental/socket: Use __exchange instead
        of std::exchange.
        * src/filesystem/ops-common.h: Likewise.
        * testsuite/20_util/default_delete/48631_neg.cc: Adjust expected
        errors to not use a hardcoded line number.
        * testsuite/20_util/default_delete/void_neg.cc: Likewise.
        * testsuite/20_util/specialized_algorithms/uninitialized_copy/constrained.cc:
        Include <utility> for std::as_const.
        * testsuite/20_util/specialized_algorithms/uninitialized_default_construct/constrained.cc:
        Likewise.
        * testsuite/20_util/specialized_algorithms/uninitialized_move/constrained.cc:
        Likewise.
        * testsuite/20_util/specialized_algorithms/uninitialized_value_construct/constrained.cc:
        Likewise.
        * testsuite/23_containers/vector/cons/destructible_debug_neg.cc:
        Adjust dg-error line number.

2021-07-27  Jonathan Wakely  <jwakely@redhat.com>

        * 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.

2021-07-23  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/future: Include <bits/atomic_base.h> instead of
        <atomic>.

2021-07-23  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/stl_relops.h: Update documentation comments.

2021-07-22  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101583
        * include/bits/hashtable.h (_Hashtable): Replace mixin with
        _Enable_default_ctor. Construct it explicitly in all
        non-forwarding, non-defaulted constructors.
        * testsuite/23_containers/unordered_map/cons/default.cc: Check
        non-default constructors can be used.
        * testsuite/23_containers/unordered_set/cons/default.cc:
        Likewise.

2021-07-22  David Edelsohn  <dje.gcc@gmail.com>

        * config/os/aix/os_defines.h (__LIBC_NO_CPP_MATH_OVERLOADS__): Define.

2021-07-22  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/94295
        * include/ext/new_allocator.h (_GLIBCXX_OPERATOR_NEW)
        (_GLIBCXX_OPERATOR_DELETE, _GLIBCXX_SIZED_DEALLOC): Define.
        (allocator::allocate, allocator::deallocate): Use new macros.

2021-07-22  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101571
        * include/bits/ranges_uninitialized.h (_DestroyGuard): Change
        constructor parameter to reference and use addressof.
        * testsuite/util/testsuite_iterators.h: Define deleted operator&
        overloads for test iterators.

2021-07-22  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/std_function.h (_Function_base): Add
        default member initializers and define constructor as defaulted.
        (function::_M_invoker): Add default member initializer.

2021-07-22  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100682
        * doc/xml/manual/debug_mode.xml: Update documentation about
        debug capability of std::array.
        * doc/html/*: Regenerate.
        * include/debug/array: New file.

2021-07-21  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101542
        * include/ext/rope (sequence_buffer): Add move constructor and
        move assignment operator.
        * testsuite/ext/rope/101542.cc: New test.

2021-07-20  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101510
        * src/c++17/fs_ops.cc (fs::create_directories): Use status
        instead of symlink_status.
        * src/filesystem/ops.cc (fs::create_directories): Likewise.
        * testsuite/27_io/filesystem/operations/create_directories.cc:
        Check symlink to existing directory.
        * testsuite/27_io/filesystem/operations/create_directory.cc: Do
        not test with symlinks on Windows.
        * testsuite/experimental/filesystem/operations/create_directories.cc:
        Check symlink to existing directory.
        * testsuite/experimental/filesystem/operations/create_directory.cc:
        Do not test with symlinks on Windows.

2021-07-20  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100863
        * include/bits/hashtable.h (_Hashtable): Conditionally delete
        default constructor by deriving from _Enable_special_members.
        * testsuite/23_containers/unordered_map/cons/default.cc: New test.
        * testsuite/23_containers/unordered_set/cons/default.cc: New test.

2021-07-20  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101510
        * src/c++17/fs_ops.cc (create_dir): Adjust whitespace.
        * testsuite/27_io/filesystem/operations/create_directory.cc:
        Test creating directory with name of existing symlink to
        directory.
        * testsuite/experimental/filesystem/operations/create_directory.cc:
        Likewise.

2021-07-16  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/tuple (get<I>): Add deleted overload for bad
        index.
        * testsuite/20_util/tuple/element_access/get_neg.cc: Adjust
        expected errors.

2021-07-16  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/max_size_type.h (numeric_limits<__max_size_type>):
        Use __int_traits unconditionally.

2021-07-16  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/random.h (_Shift::__value): Use constexpr.
        (_Select_uint_least_t::type): Use using-declaration.
        (_Mod): Likewise.
        * testsuite/26_numerics/random/pr60037-neg.cc: Adjust dg-error
        line number.

2021-07-16  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/cpp_type_traits.h (__INT_N): Use __extension__
        instead of diagnostic pragmas.
        * include/bits/functional_hash.h: Likewise.
        * include/bits/iterator_concepts.h (__is_signed_int128)
        (__is_unsigned_int128): Likewise.
        * include/bits/max_size_type.h (__max_size_type): Likewise.
        (numeric_limits<__max_size_type>): Likewise.
        * include/bits/std_abs.h (abs): Likewise.
        * include/bits/stl_algobase.h (__size_to_integer): Likewise.
        * include/bits/uniform_int_dist.h (uniform_int_distribution):
        Likewise.
        * include/ext/numeric_traits.h (_GLIBCXX_INT_N_TRAITS):
        Likewise.
        * include/std/type_traits (__is_integral_helper<INT_N>)
        (__is_signed_integer, __is_unsigned_integer)
        (__make_unsigned<INT_N>, __make_signed<INT_N>): Likewise.
        * include/std/limits (__INT_N): Add __extension__ keyword.
        * include/bits/random.h (_Select_uint_least_t)
        (random_device): Likewise.

2021-07-16  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/101231
        * include/std/ranges (_CachedPosition::_M_get): For non-forward
        ranges, just call __builtin_unreachable.
        * testsuite/std/ranges/istream_view.cc (test05): New test.

2021-07-16  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/101214
        * include/std/ranges (split_view::split_view): Use std::move.
        (split_view::_Iterator::_Iterator): Remove redundant
        default_initializable constraint.
        (split_view::_Sentinel::_Sentinel): Declare.
        * testsuite/std/ranges/adaptors/split.cc (test02): New test.

2021-07-16  Marek Polacek  <polacek@redhat.com>

        * testsuite/20_util/ratio/operations/ops_overflow_neg.cc: Add
        dg-error.

2021-07-16  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/unique_ptr.h: Adjust doxygen markup.

2021-07-16  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101307
        * include/std/type_traits: Adjust doxygen markup.

2021-07-16  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/cpp_type_traits.h: Add diagnostic pragmas around
        uses of non-standard integer types.
        * include/bits/functional_hash.h: Likewise.
        * include/bits/iterator_concepts.h: Likewise.
        * include/bits/max_size_type.h: Likewise.
        * include/bits/std_abs.h: Likewise.
        * include/bits/stl_algobase.h: Likewise.
        * include/bits/uniform_int_dist.h: Likewise.
        * include/ext/numeric_traits.h: Likewise.
        * include/std/type_traits: Likewise.

2021-07-15  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101427
        * include/std/tuple (tuple_element): Improve static_assert text.
        (__get_helper): Add deleted overload.
        (get<i>(tuple<T...>&&), get<i>(const tuple<T...>&&)): Use
        __get_helper directly.
        (__get_helper2): Remove.
        (__find_uniq_type_in_pack): New constexpr helper function.
        (get<T>): Use __find_uniq_type_in_pack and __get_helper instead
        of __get_helper2.
        * testsuite/20_util/tuple/element_access/get_neg.cc: Adjust
        expected errors.
        * testsuite/20_util/tuple/element_access/101427.cc: New test.

2021-07-15  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101429
        * include/bits/c++config (__replacement_assert): Add noexcept.
        [!_GLIBCXX_VERBOSE] (__glibcxx_assert_impl): Use __builtin_abort
        instead of __replacement_assert.

2021-07-14  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/string_view (basic_string_view(It, End)): Add
        noexcept-specifier.
        * testsuite/21_strings/basic_string_view/cons/char/range.cc:
        Check noexcept-specifier. Also check construction without CTAD.

2021-07-13  Jonathan Wakely  <jwakely@redhat.com>

        PR c++/101361
        * include/std/string_view (ends_with): Use traits_type::compare
        directly.

2021-07-13  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/string_view: Only include <bits/ranges_base.h>
        once, and only for C++20 and later.

2021-07-12  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101411
        * include/std/span (as_writable_bytes): Add requires-clause.
        * testsuite/23_containers/span/101411.cc: New test.

2021-07-09  Matheus Castanho  <msc@linux.ibm.com>

        * include/std/mutex (__lock_impl): Check
        _GLIBCXX_HAS_GTHREADS before using __gthread_yield.

2021-07-02  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101271
        * include/bits/unique_ptr.h (unique_ptr<T[],D>::operator[]):
        Remove noexcept-specifier.
        (unique_ptr<T[],D>::_S_nothrow_deref): Remove.
        * testsuite/20_util/unique_ptr/lwg2762.cc: Remove checks for
        operator[].

2021-07-01  Jonathan Wakely  <jwakely@redhat.com>

        * doc/doxygen/doxygroups.cc: Fix docs for std::literals.
        * doc/doxygen/user.cfg.in: Exclude the Networking TS header.
        Add some more predefined macros.
        * include/bits/fs_fwd.h: Move @addtogroup commands inside
        namespaces. Add better documentation.
        * include/bits/fs_path.h: Likewise.
        * include/experimental/bits/fs_fwd.h: Likewise.
        * include/experimental/bits/fs_path.h: Likewise.
        * include/ext/throw_allocator.h: Fix typo and improve docs.
        * include/std/chrono: Move @addtogroup commands.
        * include/std/system_error: Move @addtogroup commands.
        * libsupc++/exception: Improve documentation.
        * libsupc++/exception.h: Add @since documentation.

2021-06-30  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101258
        * doc/doxygen/user.cfg.in (INPUT): Add <experimental/simd>.
        (COLS_IN_ALPHA_INDEX): Remove obsolete tag.
        (PREDEFINED): Add/fix some more macros that need to be expanded.
        * include/bits/random.h: Stop Doxygen from documenting internal
        implementation details.
        * include/bits/random.tcc: Likewise.
        * include/bits/this_thread_sleep.h: Fix @file name.
        * include/experimental/bits/simd.h: Add to Doxygen group. Do not
        document internal implementation details.
        * include/experimental/bits/simd_detail.h: Do not document
        internal implementation details.
        * include/experimental/simd: Define Doxygen groups.
        * include/experimental/type_traits: Improve documentation for
        the header file. Define groups. Use @since commands.
        * include/std/scoped_allocator (scoped_allocator_adaptor): Move
        declaration before undocumented region.
        * include/std/type_traits (true_type, false_type): Use using
        declaration instead of typedef.
        (is_invocable_v, is_nothrow_invocable_v, is_invocable_r_v)
        (is_nothrow_invocable_r_v): Move definitions next to other C++17
        variable templates.
        Do not document internal implementation details. Move misplaced
        group-end command. Define group for variable templates.
        * include/std/variant: Do not document internal implementation
        details.
        * testsuite/26_numerics/random/pr60037-neg.cc: Adjust dg-error
        line number.

2021-06-30  Jonathan Wakely  <jwakely@redhat.com>

        * include/experimental/simd: Do not define anything pre-C++17.

2021-06-30  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/random.tcc [__cpp_inline_variables]: Remove
        redundant definitions of static constexpr member variables.
        * testsuite/26_numerics/random/pr60037-neg.cc: Adjust dg-error
        line number.

2021-06-28  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/streambuf.tcc (__copy_streambufs_eof): Remove
        explicit instantiation declarations.
        * src/c++11/streambuf-inst.cc (__copy_streambufs_eof): Remove
        explicit instantiation definitions.

2021-06-28  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/97088
        * testsuite/17_intro/names.cc: Fix #if condition for names used
        by newlib headers.

2021-06-28  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101236
        * include/bits/unique_ptr.h (unique_ptr<T[], D>::operator[]):
        Fail gracefully if element_type is incomplete.
        * testsuite/20_util/unique_ptr/cons/incomplete.cc: Clarify that
        the standard doesn't require this test to work for array types.
        * testsuite/20_util/unique_ptr/lwg2762.cc: Check that incomplete
        types can be used with array specialization.
        * testsuite/20_util/unique_ptr/101236.cc: New test.

2021-06-28  Jonathan Wakely  <jwakely@redhat.com>

        * doc/xml/manual/intro.xml: Document LWG 415 change.
        * doc/html/manual/bugs.html: Regenerate.
        * include/bits/istream.tcc (ws): Create sentry and catch
        exceptions.
        * testsuite/27_io/basic_istream/ws/char/lwg415.cc: New test.
        * testsuite/27_io/basic_istream/ws/wchar_t/lwg415.cc: New test.

2021-06-25  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/ostream.tcc (basic_ostream::write): Call sputn
        directly instead of using _M_write. Do setstate(__err) all
        outside the try-catch block.
        * include/std/ostream (basic_ostream::_M_write): Declare
        private. Use __ostream_insert. Do not define for the versioned
        namespace.

2021-06-25  Jonathan Wakely  <jwakely@redhat.com>

        * doc/xml/manual/intro.xml: Document LWG 581 change.
        * doc/html/manual/bugs.html: Regenerate.
        * include/bits/basic_ios.tcc: Whitespace.
        * include/bits/ostream.tcc (basic_ostream::flush()): Construct
        sentry.
        * testsuite/27_io/basic_ostream/flush/char/2.cc: Check
        additional cases.
        * testsuite/27_io/basic_ostream/flush/char/exceptions_badbit_throw.cc:
        Likewise.
        * testsuite/27_io/basic_ostream/flush/wchar_t/2.cc: Likewise.
        * testsuite/27_io/basic_ostream/flush/wchar_t/exceptions_badbit_throw.cc:
        Likewise.

2021-06-25  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/ostream.tcc (sentry): Only set failbit if badbit
        is set, not if eofbit is set.
        (tellp, seekp, seekp): Create sentry object. Do not set badbit
        on exceptions.
        * testsuite/27_io/basic_ostream/seekp/char/exceptions_badbit_throw.cc:
        Adjust expected behaviour.
        * testsuite/27_io/basic_ostream/seekp/wchar_t/exceptions_badbit_throw.cc:
        Likewise.
        * testsuite/27_io/basic_ostream/tellp/char/exceptions_badbit_throw.cc:
        Likewise.
        * testsuite/27_io/basic_ostream/tellp/wchar_t/exceptions_badbit_throw.cc:
        Likewise.
        * testsuite/27_io/basic_ostream/seekp/char/n3168.cc: New test.
        * testsuite/27_io/basic_ostream/seekp/wchar_t/n3168.cc: New test.
        * testsuite/27_io/basic_ostream/tellp/char/n3168.cc: New test.
        * testsuite/27_io/basic_ostream/tellp/wchar_t/n3168.cc: New test.

2021-06-25  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/syncstream (basic_syncbuf::swap()): Remove
        noexcept, as per LWG 3498.

2021-06-25  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/97088
        * testsuite/17_intro/names.cc: Undef more names for newlib and
        also for arm-none-linux-gnueabi.
        * testsuite/experimental/names.cc: Disable PCH.

2021-06-25  Matthias Kretz  <m.kretz@gsi.de>

        * include/experimental/bits/simd.h (__bit_cast): Implement via
        __builtin_bit_cast #if available.
        (__proposed::simd_bit_cast): Add overloads for simd and
        simd_mask, which use __builtin_bit_cast (or __bit_cast #if not
        available), which return an object of the requested type with
        the same bits as the argument.
        * include/experimental/bits/simd_math.h: Use simd_bit_cast
        instead of __bit_cast to allow casts to fixed_size_simd.
        (copysign): Remove branch that was only required if __bit_cast
        cannot be constexpr.
        * testsuite/experimental/simd/tests/bits/test_values.h: Switch
        from __bit_cast to __proposed::simd_bit_cast since the former
        will not cast fixed_size objects anymore.

2021-06-24  Matthias Kretz  <m.kretz@gsi.de>

        * include/experimental/bits/simd_math.h
        (_GLIBCXX_SIMD_MATH_CALL2_): Rename arg2_ to __arg2.
        (_GLIBCXX_SIMD_MATH_CALL3_): Rename arg2_ to __arg2 and arg3_ to
        __arg3.

2021-06-24  Matthias Kretz  <m.kretz@gsi.de>

        * include/experimental/bits/simd.h (__execute_on_index_sequence)
        (__execute_on_index_sequence_with_return)
        (__call_with_n_evaluations, __call_with_subscripts): Add flatten
        attribute.

2021-06-24  Matthias Kretz  <m.kretz@gsi.de>

        * include/experimental/bits/simd_x86.h (_S_trunc, _S_floor)
        (_S_ceil): Set bit 8 (_MM_FROUND_NO_EXC) on AVX and SSE4.1
        roundp[sd] calls.

2021-06-24  Matthias Kretz  <m.kretz@gsi.de>

        * include/experimental/bits/simd_x86.h (_S_ldexp): The AVX512F
        implementation doesn't require a _VecBltnBtmsk ABI tag, it
        requires either a 64-Byte input (in which case AVX512F must be
        available) or AVX512VL.

2021-06-24  Matthias Kretz  <m.kretz@gsi.de>

        * include/experimental/bits/simd_math.h: Undefine internal
        macros after use.
        (frexp): Move #if to a more sensible position and reformat
        preceding code.
        (logb): Call _SimdImpl::_S_logb for fixed_size instead of
        duplicating the code here.
        (modf): Simplify condition.

2021-06-24  Matthias Kretz  <m.kretz@gsi.de>

        * include/experimental/bits/simd_math.h (fabs): Remove
        fabs(simd<integral>) overload.

2021-06-24  Matthias Kretz  <m.kretz@gsi.de>

        * include/experimental/bits/simd_converter.h
        (_SimdConverter::operator()): Pass _SimdTuple by const-ref.
        * include/experimental/bits/simd_fixed_size.h
        (_GLIBCXX_SIMD_FIXED_OP): Pass binary operator _SimdTuple
        arguments by const-ref.
        (_S_masked_unary): Pass _SimdTuple by const-ref.

2021-06-24  Matthias Kretz  <m.kretz@gsi.de>

        * include/experimental/bits/simd_fixed_size.h
        (_AbisInSimdTuple): Removed.

2021-06-24  Matthias Kretz  <m.kretz@gsi.de>

        * include/experimental/bits/simd.h: Add missing operator~
        overload for simd<floating-point> to __float_bitwise_operators.
        * include/experimental/bits/simd_builtin.h
        (_SimdImplBuiltin::_S_complement): Bitcast to int (and back) to
        implement complement for floating-point vectors.
        * include/experimental/bits/simd_fixed_size.h
        (_SimdImplFixedSize::_S_copysign): New function, forwarding to
        copysign implementation of _SimdTuple members.
        * include/experimental/bits/simd_math.h (copysign): Call
        _SimdImpl::_S_copysign for fixed_size arguments. Simplify
        generic copysign implementation using the new ~ operator.

2021-06-24  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/experimental/simd/README.md: Fix typos.

2021-06-24  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/shared_ptr_base.h (__shared_ptr_access::operator[]):
        Add noexcept.
        * include/bits/unique_ptr.h (unique_ptr::operator*): Add
        conditional noexcept as per LWG 2762.
        * testsuite/20_util/shared_ptr/observers/array.cc: Check that
        dereferencing cannot throw.
        * testsuite/20_util/shared_ptr/observers/get.cc: Likewise.
        * testsuite/20_util/optional/observers/lwg2762.cc: New test.
        * testsuite/20_util/unique_ptr/lwg2762.cc: New test.

2021-06-23  Patrick Palka  <ppalka@redhat.com>

        PR c++/101174
        * testsuite/23_containers/multiset/cons/deduction.cc:
        Uncomment CTAD example that was rejected by this bug.
        * testsuite/23_containers/set/cons/deduction.cc: Likewise.

2021-06-23  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/chrono (chrono::year::is_leap()): Fix incorrect
        logic in comment.

2021-06-23  Matthias Kretz  <m.kretz@gsi.de>

        * testsuite/experimental/simd/README.md: New file.

2021-06-23  Matthias Kretz  <m.kretz@gsi.de>

        * testsuite/experimental/simd/driver.sh: Rewrite output
        verbosity logic. Add -p/--percentage option. Allow -v/--verbose
        to be used twice. Add -x and -o short options. Parse long
        options with = instead of separating space generically. Parce
        contracted short options. Make unrecognized options an error.
        If same-line output is active, trap on EXIT to increment the
        progress (only with --percentage), erase the line and print the
        current status.
        * testsuite/experimental/simd/generate_makefile.sh: Initialize
        helper files for progress account keeping. Update help target
        for changes to DRIVEROPTS.

2021-06-23  Matthias Kretz  <m.kretz@gsi.de>

        * testsuite/Makefile.am (check-simd): Remove -fno-tree-vrp flag
        and associated warning.
        * testsuite/Makefile.in: Regenerate.

2021-06-23  Cassio Neri  <cassio.neri@gmail.com>
            Jonathan Wakely  <jwakely@redhat.com>
            Ulrich Drepper  <drepper@redhat.com>

        * include/std/chrono (chrono::year::is_leap()): Optimize.

2021-06-23  Patrick Palka  <ppalka@redhat.com>

        PR c++/86439
        * testsuite/23_containers/map/cons/deduction.cc: Replace ambiguous
        CTAD examples.
        * testsuite/23_containers/multimap/cons/deduction.cc: Likewise.
        * testsuite/23_containers/multiset/cons/deduction.cc: Likewise.
        Mention one of the replaced examples is broken due to PR101174.
        * testsuite/23_containers/set/cons/deduction.cc: Likewise.
        * testsuite/23_containers/unordered_map/cons/deduction.cc: Replace
        ambiguous CTAD examples.
        * 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.

2021-06-23  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/mutex (__detail::__try_lock_impl): Rename
        parameter to avoid clashing with newlib's __lockable macro.
        (try_lock): Add 'inline' specifier.
        * testsuite/17_intro/names.cc: Add check for __lockable.
        * testsuite/30_threads/try_lock/5.cc: Add options for pthreads.

2021-06-22  Jonathan Wakely  <jwakely@redhat.com>
            Matthias Kretz  <m.kretz@gsi.de>

        * include/std/mutex (lock): Replace recursion with iteration
        when lockables all have the same type.
        (__detail::__try_lock_impl): Likewise. Pass lockables as
        parameters, instead of a tuple. Always lock the first one, and
        recurse for the rest.
        (__detail::__lock_impl): Adjust call to __try_lock_impl.
        (__detail::__try_to_lock): Remove.
        * testsuite/30_threads/lock/3.cc: Check that mutexes are locked.
        * testsuite/30_threads/lock/4.cc: Also test non-heterogeneous
        arguments.
        * testsuite/30_threads/unique_lock/cons/60497.cc: Also check
        std::try_lock.
        * testsuite/30_threads/try_lock/5.cc: New test.

2021-06-22  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/memory (declare_reachable, undeclare_reachable)
        (declare_no_pointers, undeclare_no_pointers, get_pointer_safety)
        (pointer_safety): Only define for C++11 to C++20 inclusive.
        * testsuite/20_util/pointer_safety/1.cc: Do not run for C++23.

2021-06-22  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/random.h (seed_seq): Constrain initializer-list
        constructor.
        * include/bits/random.tcc (seed_seq): Add template parameter.
        * testsuite/26_numerics/random/seed_seq/cons/default.cc: Check
        for noexcept.
        * testsuite/26_numerics/random/seed_seq/cons/initlist.cc: Check
        constraints.

2021-06-22  Thomas Rodgers  <rodgert@appliantology.com>

        PR libstdc++/100806
        * include/bits/semaphore_base.h (__atomic_semaphore::_M_release):
        Force _M_release() to wake all waiting threads.
        * testsuite/30_threads/semaphore/100806.cc: New test.

2021-06-21  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/mutex (__try_to_lock): Move to __detail namespace.
        (struct __try_lock_impl): Replace with ...
        (__detail::__try_lock_impl<Idx>(tuple<Lockables...>&)): New
        function templates to implement std::try_lock.
        (try_lock): Use new __try_lock_impl.
        (__detail::__lock_impl(int, int&, L0&, L1&...)): New function
        template to implement std::lock.
        (lock): Use __lock_impl.

2021-06-21  Patrick Palka  <ppalka@redhat.com>

        * include/bits/ranges_cmp.h (__cpp_lib_ranges): Adjust value.

2021-06-20  Patrick Palka  <ppalka@redhat.com>

        * include/std/ranges (__non_propagating_cache::operator bool):
        Define for split_view::begin().
        (split_view): Define as per P2210.
        (views::__detail::__can_split_view): Define.
        (views::_Split, views::split): Define.
        * testsuite/std/ranges/adaptors/100577.cc (test01, test02):
        Test views::split.
        * testsuite/std/ranges/adaptors/split.cc: New test.
        * testsuite/std/ranges/p2325.cc (test08a): New test.
        * testsuite/std/ranges/p2367.cc (test01): Test views::split.

2021-06-20  Patrick Palka  <ppalka@redhat.com>

        * include/std/ranges: Rename views::split to views::lazy_split,
        split_view to lazy_split_view, etc. throughout.
        * testsuite/std/ranges/*: Likewise.
        * testsuite/std/ranges/adaptors/lazy_split.cc: New file.
        * testsuite/std/ranges/adaptors/lazy_split_neg.cc: New file.

2021-06-20  Patrick Palka  <ppalka@redhat.com>

        * include/std/ranges (split_view::_OuterIter::__at_end):
        Check _M_trailing_empty.
        (split_view::_OuterIter::_M_trailing_empty): Define this
        data member.
        (split_view::_OuterIter::operator++): Set _M_trailing_empty
        appropriately.
        (split_view::_OuterIter::operator==): Compare
        _M_trailing_empty.
        * testsuite/std/ranges/adaptors/100479.cc (test03): Expect two
        split parts instead of one.
        * testsuite/std/ranges/adaptors/split.cc (test11): New test.

2021-06-20  Patrick Palka  <ppalka@redhat.com>

        * include/std/ranges (split_view::_InnerIter::base): Define as
        per P2210.

2021-06-19  Patrick Palka  <ppalka@redhat.com>

        * include/std/ranges (transform_view::_Iterator::_S_iter_concept):
        Consider _Base instead of _Vp as per LWG 3555.
        (elements_view::_Iterator::_S_iter_concept): Likewise.

2021-06-19  Patrick Palka  <ppalka@redhat.com>

        * include/std/ranges (split_view::_OuterIter::value_type::begin):
        Remove the non-const overload, and remove the copyable constraint
        on the const overload as per LWG 3553.

2021-06-19  Patrick Palka  <ppalka@redhat.com>

        * include/bits/stl_iterator.h
        (__detail::__common_iter_use_postfix_proxy): Add
        move_constructible constraint as per LWG 3546.
        (common_iterator::__postfix_proxy): Adjust initializer of
        _M_keep as per LWG 3546.

2021-06-18  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/100387
        * include/bits/ranges_algo.h (__minmax_fn::operator()): Rewrite
        to limit comparison complexity to 3*N/2.
        (__minmax_element_fn::operator()): Likewise.
        (shift_right): Avoid premature std::move of __result.
        * testsuite/25_algorithms/minmax/constrained.cc (test04, test05):
        New tests.
        * testsuite/25_algorithms/minmax_element/constrained.cc (test02):
        Likewise.

2021-06-18  Patrick Palka  <ppalka@redhat.com>

        * include/std/concepts (convertible_to): Just use declval as per
        LWG 3557.

2021-06-18  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/95833
        * include/std/numeric (reduce(Iter, Iter, T, BinaryOp)): Replace
        incorrect static_assert with ones matching the 'Mandates'
        conditions in the standard.
        * testsuite/26_numerics/reduce/95833.cc: New test.

2021-06-18  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/21_strings/basic_string/cons/char/1.cc: Use
        diagnostic pragma to suppress -Wstringop-overread error.

2021-06-18  Patrick Palka  <ppalka@redhat.com>

        * include/bits/ranges_algo.h (__find_fn, find, __find_if_fn)
        (find_if, __find_if_not_fn, find_if_not, _in_in_result)
        (__mismatch_fn, mismatch, __search_fn, search): Move to ...
        * include/bits/ranges_util.h: ... here.
        * include/std/ranges (__detail::find, __detail::find_if)
        (__detail::find_if_not, __detail::mismatch): Remove.
        (filter_view): Use ranges::find_if instead.
        (drop_while_view): Use ranges::find_if_not instead.
        (split_view): Use ranges::find and ranges::mismatch instead.

2021-06-18  Patrick Palka  <ppalka@redhat.com>

        * 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  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/91488
        * 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.

2021-06-17  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/100940
        * include/std/ranges (__adaptor::_Partial): For the "simple"
        forwarding partial specializations, also require that
        the extra arguments are trivially copyable.
        * testsuite/std/ranges/adaptors/100577.cc (test04): New test.

2021-06-17  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/100940
        * include/std/ranges (__adaptor::_RangeAdaptor): Document the
        template form of _S_has_simple_extra_args.
        (__adaptor::__adaptor_has_simple_extra_args): Add _Args template
        parameter pack.  Try to treat _S_has_simple_extra_args as a
        variable template parameterized by _Args.
        (__adaptor::_Partial): Pass _Arg/_Args to the constraint
        __adaptor_has_simple_extra_args.
        (views::_Take::_S_has_simple_extra_args): Templatize according
        to the type of the extra argument.
        (views::_Drop::_S_has_simple_extra_args): Likewise.
        (views::_Split::_S_has_simple_extra_args): Define.
        * testsuite/std/ranges/adaptors/100577.cc (test01, test02):
        Adjust after changes to _S_has_simple_extra_args mechanism.
        (test03): Define.

2021-06-16  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/iterator_concepts.h (__decay_copy): Name type.

2021-06-16  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/ranges_base.h (ranges::begin, ranges::end)
        (ranges::cbegin, ranges::cend, ranges::rbeing, ranges::rend)
        (ranges::crbegin, ranges::crend, ranges::size, ranges::ssize)
        (ranges::empty, ranges::data, ranges::cdata): Remove final
        keywords and deleted operator& overloads.
        * testsuite/24_iterators/customization_points/iter_move.cc: Use
        new is_customization_point_object function.
        * testsuite/24_iterators/customization_points/iter_swap.cc:
        Likewise.
        * testsuite/std/concepts/concepts.lang/concept.swappable/swap.cc:
        Likewise.
        * testsuite/std/ranges/access/begin.cc: Likewise.
        * testsuite/std/ranges/access/cbegin.cc: Likewise.
        * testsuite/std/ranges/access/cdata.cc: Likewise.
        * testsuite/std/ranges/access/cend.cc: Likewise.
        * testsuite/std/ranges/access/crbegin.cc: Likewise.
        * testsuite/std/ranges/access/crend.cc: Likewise.
        * testsuite/std/ranges/access/data.cc: Likewise.
        * testsuite/std/ranges/access/empty.cc: Likewise.
        * testsuite/std/ranges/access/end.cc: Likewise.
        * testsuite/std/ranges/access/rbegin.cc: Likewise.
        * testsuite/std/ranges/access/rend.cc: Likewise.
        * testsuite/std/ranges/access/size.cc: Likewise.
        * testsuite/std/ranges/access/ssize.cc: Likewise.
        * testsuite/util/testsuite_iterators.h
        (is_customization_point_object): New function.

2021-06-15  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/ranges_base.h (ranges::begin, ranges::end)
        (ranges::cbegin, ranges::cend, ranges::rbeing, ranges::rend)
        (ranges::crbegin, ranges::crend, ranges::size, ranges::ssize)
        (ranges::empty, ranges::data, ranges::cdata): Make types final.
        Add deleted operator& overloads.
        (ranges::advance, ranges::distance, ranges::next, ranges::prev):
        Likewise.
        * testsuite/std/ranges/headers/ranges/synopsis.cc: Replace
        ill-formed & expressions with using-declarations. Add checks for
        other function objects.

2021-06-15  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/ranges_util.h (view_interface): Add noexcept to
        empty, operator bool, data and size members.
        (subrange): Add noexcept to constructors.
        * include/std/ranges (single_view, ref_view): Add noexcept to
        constructors.
        (views::single, views::all): Add noexcept.
        * testsuite/std/ranges/adaptors/all.cc: Check noexcept.
        * testsuite/std/ranges/single_view.cc: Likewise.

2021-06-15  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/ranges_util.h (subrange): Add __size_type typedef
        and use it to simplify declarations.
        (subrange(i, s, n)): Remove assertion.
        * testsuite/std/ranges/subrange/constexpr.cc: New test.

2021-06-15  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/iterator_concepts.h (__cust_access::__decay_copy):
        Replace with function object.
        (__cust_access::__member_begin, ___cust_access::_adl_begin): Use
        __decay_copy unqualified.
        * include/bits/ranges_base.h (__member_end, __adl_end):
        Likewise. Use __range_iter_t for type of ranges::begin.
        (__member_rend): Use correct value category for rbegin argument.
        (__member_data): Use __decay_copy unqualified.
        (__begin_data): Use __range_iter_t for type of ranges::begin.

2021-06-14  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/ranges_base.h (ranges::empty): Check whether
        conversion to bool can throw.
        * testsuite/std/ranges/access/empty.cc: Check for correct
        noexcept-specifier.

2021-06-14  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100894
        * include/std/type_traits (__common_ref_impl<X&, Y&>): Only
        use the type if it's a reference.
        * testsuite/20_util/common_reference/100894.cc: New test.

2021-06-14  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/experimental/filesystem/path/native/conv_c++23.cc:
        Add dg-require-filesystem-ts directive.

2021-06-14  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101034
        * include/std/any (any(in_place_t<T>, initializer_list<U>, A&&...))
        (any::emplace<T>(initializer_list<U>, A&&...)): Fix constraint
        to use lvalue.
        * testsuite/20_util/any/cons/101034.cc: New test.

2021-06-14  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/17_intro/headers/c++2017/all_attributes.cc: Add
        -std=gnu++17 option.

2021-06-14  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101056
        * libsupc++/compare (compare_partial_order_fallback): Add
        constraint using reversed parameter order, as per LWG 3465.
        * testsuite/18_support/comparisons/algorithms/fallback.cc:
        Adjust expected result.

2021-06-14  Jonathan Wakely  <jwakely@redhat.com>

        * libsupc++/compare (__decayed_same_as): New helper concept.
        (strong_order, weak_order, partial_order): Constrain with new
        concept instead of using static_assert.
        (compare_strong_order_fallback, compare_weak_order_fallback)
        (compare_partial_order_fallback): Likewise. Do not deduce return
        types. Remove redundant if-constexpr checks.
        * testsuite/18_support/comparisons/algorithms/fallback.cc: New test.

2021-06-14  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/101055
        * include/std/tuple: Use reserved form of attribute name.
        * testsuite/17_intro/headers/c++2011/all_attributes.cc: Add
        check for no_unique_address.
        * testsuite/17_intro/headers/c++2014/all_attributes.cc:
        Likewise.
        * testsuite/17_intro/headers/c++2017/all_attributes.cc:
        Likewise.

2021-06-11  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/fs_path.h (operator==, operator<=>): Use new
        _S_compare function.
        (path::_S_compare): New function to call path::compare in a
        context where path::iterator is complete.
        * include/experimental/bits/fs_path.h (operator<, operator==):
        Define after path::iterator is complete.
        * testsuite/27_io/filesystem/path/native/conv_c++23.cc: New
        test.
        * testsuite/experimental/filesystem/path/native/conv_c++23.cc:
        New test.

2021-06-09  Thomas Rodgers  <rodgert@appliantology.com>

        * testsuite/29_atomics/atomic_ref/wait_notify.cc: Guard
        test logic with constexpr check for is_always_lock_free.

2021-06-09  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100982
        * include/std/optional (optional::operator=(const optional<U>&)):
        Fix value category used in is_assignable check.
        * testsuite/20_util/optional/assignment/100982.cc: New test.

2021-06-09  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/allocator.h (allocator::is_always_equal): Deprecate.
        * include/bits/iterator_concepts.h (indirectly_readable_traits):
        Add LWG issue number to comment.
        * include/std/memory_resource (polymorphic_allocator::release):
        Deprecate.
        * testsuite/20_util/allocator/requirements/typedefs.cc: Add
        dg-warning for deprecation. Also check std::allocator<void>.

2021-06-08  Thomas Rodgers  <rodgert@appliantology.com>

        PR libstdc++/100889
        * include/bits/atomic_base.h (atomic_ref<_Tp*>::wait):
        Change parameter type from _Tp to _Tp*.
        * testsuite/29_atomics/atomic_ref/wait_notify.cc: Extend
        coverage of types tested.

2021-06-08  Thomas Rodgers  <rodgert@appliantology.com>

        * include/std/barrier (__tree_barrier::_M_arrive): Remove
        unnecessary hasher instantiation.

2021-06-08  Jonathan Wakely  <jwakely@redhat.com>

        * include/experimental/propagate_const (swap): Constrain.
        * testsuite/experimental/propagate_const/swap/lwg3413.cc: New test.

2021-06-07  Avi Kivity  <avi@scylladb.com>

        PR libstdc++/100900
        * include/std/ranges (elements_view::__iter_cat::_S_iter_cat):
        Add missing typename.

2021-06-07  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/98842
        * include/std/optional (operator<=>(const optional<T>& const U&)):
        Add missing constraint and add workaround for template
        recursion.
        * testsuite/20_util/optional/relops/three_way.cc: Check that
        type without equality comparison cannot be compared when wrapped
        in std::optional.

2021-06-05  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100824
        * include/bits/ranges_base.h (_SSize): Return signed type.
        * testsuite/std/ranges/access/ssize.cc: Check with __int128.

2021-06-04  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/ranges_base.h (_SSize): Return the result of
        ranges::size converted to the wider of make-signed-like-t<S> and
        ptrdiff_t, rather than the ranges different type.
        * testsuite/std/ranges/access/ssize.cc: Adjust expected result
        for an iota_view that uses an integer class type for its
        difference_type.

2021-06-04  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100824
        * include/bits/ranges_base.h (__member_data): Use __decay_copy.
        * testsuite/std/ranges/access/data.cc: Add testcase from PR.

2021-06-04  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100824
        * include/bits/iterator_concepts.h (__detail::__decay_copy)
        (__detail::__member_begin, __detail::__adl_begin): Move to
        namespace ranges::__cust_access.
        (__detail::__ranges_begin): Likewise, and rename to __begin.
        Remove redundant static assertion.
        * include/bits/ranges_base.h (_Begin, _End, _RBegin, _REnd):
        Use lvalue in noexcept specifier.
        (__as_const): Add non-deduced parameter for value category.
        (_CBegin, _CEnd, _CRBegin, _CREnd, _CData): Adjust uses of
        __as_const.
        (__member_size, __adl_size, __member_empty, __size0_empty):
        (__eq_iter_empty, __adl_data): Use lvalue objects in
        requirements.
        (__sentinel_size): Likewise. Add check for conversion to
        unsigned-like.
        (__member_data): Allow non-lvalue types to satisfy the concept,
        but use lvalue object in requirements.
        (_Size, _SSize): Remove forwarding to always use an lvalue.
        (_Data): Likewise. Add static assertion for arrays.
        * testsuite/std/ranges/access/cdata.cc: Adjust expected
        behaviour for rvalues. Add negative tests for ill-formed
        expressions.
        * testsuite/std/ranges/access/data.cc: Likewise.
        * testsuite/std/ranges/access/empty.cc: Adjust expected
        behaviour for rvalues.
        * testsuite/std/ranges/access/size.cc: Likewise.

2021-06-04  Tim Adye  <Tim.Adye@cern.ch>

        * include/std/any (any::_Manager::_S_access): New static
        function to access the contained value.
        (any::emplace, __any_caster): Use _S_access member of the
        manager type.

2021-06-04  Jonathan Wakely  <jwakely@redhat.com>

        * 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.

2021-06-03  Patrick Palka  <ppalka@redhat.com>

        * include/bits/ranges_algo.h (__detail::__can_reread_output):
        Factor out this concept from ...
        (__unique_copy_fn::operator()): ... here.  Use the concept
        throughout.
        * testsuite/std/ranges/range.cc: Remove now ill-formed use
        of range_value_t on an output_range.
        * testsuite/util/testsuite_iterators.h (output_iterator_wrapper):
        Define value_type, pointer and reference member types to void.

2021-06-03  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/100577
        * include/std/ranges (_RangeAdaptorClosure): Document
        _S_has_simple_call_op mechanism.
        (_RangeAdaptor): Document _S_has_simple_extra_args mechanism.
        (__closure_has_simple_call_op): New concept.
        (__adaptor_has_simple_extra_args): Likewise.
        (_Partial<_Adaptor, _Args...>): New partial specialization.
        (_Partial<_Adaptor, _Arg>): Likewise.
        (_Pipe<_Lhs, _Rhs>): Likewise.
        (views::_All::_S_has_simple_call_op): Define to true.
        (views::_Filter::_S_has_simple_extra_args): Likewise.
        (views::_Transform::_S_has_simple_extra_args): Likewise.
        (views::_Take::_S_has_simple_extra_args): Likewise.
        (views::_TakeWhile::_S_has_simple_extra_args): Likewise.
        (views::_Drop::_S_has_simple_extra_args): Likewise.
        (views::_DropWhile::_S_has_simple_extra_args): Likewise.
        (views::_Join::_S_has_simple_call_op): Likewise.
        (views::_Split): Document why we don't define
        _S_has_simple_extra_args to true for this adaptor.
        (views::_Common::_S_has_simple_call_op): Define to true.
        (views::_Reverse::_S_has_simple_call_op): Likewise.
        (views::_Elements::_S_has_simple_call_op): Likewise.
        * testsuite/std/ranges/adaptors/100577.cc: New test.

2021-06-02  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100863
        PR libstdc++/65816
        * include/bits/hashtable_policy.h (_Hashtable_ebo_helper):
        Value-initialize subobject.
        * testsuite/23_containers/unordered_map/allocator/default_init.cc:
        Remove XFAIL.
        * testsuite/23_containers/unordered_set/allocator/default_init.cc:
        Remove XFAIL.

2021-06-02  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/96088
        * testsuite/23_containers/unordered_map/96088.cc: Adjust
        expected number of allocations.
        * testsuite/23_containers/unordered_set/96088.cc: Likewise.

2021-06-02  Jonathan Wakely  <jwakely@redhat.com>

        * doc/xml/manual/status_cxxis29124.xml: Improve punctuation.
        * doc/xml/manual/status_cxxtr1.xml: Likewise.
        * doc/xml/manual/status_cxxtr24733.xml: Likewise.
        * doc/html/*: Regenerate.

2021-06-01  Patrick Palka  <ppalka@redhat.com>

        PR c++/65816
        * testsuite/23_containers/deque/allocator/default_init.cc,
        testsuite/23_containers/forward_list/allocator/default_init.cc,
        testsuite/23_containers/list/allocator/default_init.cc,
        testsuite/23_containers/map/allocator/default_init.cc,
        testsuite/23_containers/set/allocator/default_init.cc,
        testsuite/23_containers/vector/allocator/default_init.cc,
        testsuite/23_containers/vector/bool/allocator/default_init.cc:
        Remove xfail.

2021-06-01  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/23_containers/unordered_map/96088.cc: Change
        effective target to c++17.
        * testsuite/23_containers/unordered_set/96088.cc: Likewise.

2021-06-01  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/22_locale/ctype/is/string/89728_neg.cc: Only test
        isblank for C++11 and later.

2021-06-01  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100833
        * include/bits/ranges_base.h (ranges::advance(iter, n, sentinel)):
        Fix return value for no-op case.
        * testsuite/24_iterators/range_operations/advance.cc: Test
        return values of three-argument overload.

2021-06-01  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99453
        * python/Makefile.am: Use archive name for printer hook if no
        dynamic library name is available.
        * python/Makefile.in: Regenerate.

2021-05-30  Gerald Pfeifer  <gerald@pfeifer.com>

        * doc/xml/manual/abi.xml: Remove dead reference to "Intel
        Compilers for Linux: Compatibility with GNU Compilers" article.
        * doc/html/manual/abi.html: Regenerate.

2021-05-26  François Dumont  <fdumont@gcc.gnu.org>

        * include/debug/formatter.h
        (_Error_formatter::_Parameter::_Named): New.
        (_Error_formatter::_Parameter::_Type): Inherit latter.
        (_Error_formatter::_Parameter::_M_integer): Likewise.
        (_Error_formatter::_Parameter::_M_string): Likewise.
        * src/c++11/debug.cc: Include <cstring>.
        (_Print_func_t): New.
        (print_raw(PrintContext&, const char*, ptrdiff_t)): New.
        (print_word): Use '%.*s' format in fprintf to render only expected number of chars.
        (pretty_print(PrintContext&, const char*, _Print_func_t)): New.
        (print_type): Rename in...
        (print_type_info): ...this. Use pretty_print.
        (print_address, print_integer): New.
        (print_named_name, print_iterator_constness, print_iterator_state): New.
        (print_iterator_seq_type): New.
        (print_named_field, print_type_field, print_instance_field, print_iterator_field): New.
        (print_field): Use latters.
        (print_quoted_named_name, print_type_type, print_type, print_instance): New.
        (print_string(PrintContext&, const char*, const _Parameter*, size_t)):
        Change signature to...
        (print_string(PrintContext&, const char*, ptrdiff_t, const _Parameter*, size_t)):
        ...this and adapt. Remove intermediate buffer to render input string.
        (print_string(PrintContext&, const char*, ptrdiff_t)): New.

2021-05-26  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100768
        * include/bits/ranges_base.h (advance, distance, next, prev):
        Replace function templates with function objects.
        * testsuite/24_iterators/headers/iterator/synopsis_c++20.cc:
        Adjust for changes to function objects.
        * testsuite/std/ranges/adaptors/elements.cc: Add using
        declarations for names from namespace ranges.
        * testsuite/std/ranges/adaptors/transform.cc: Likewise.
        * testsuite/24_iterators/range_operations/100768.cc: New test.

2021-05-24  François Dumont  <fdumont@gcc.gnu.org>

        PR libstdc++/96088
        * include/bits/hashtable_policy.h (_Select2nd): New.
        (_NodeBuilder<>): New.
        (_ReuseOrAllocNode<>::operator()): Use variadic template args.
        (_AllocNode<>::operator()): Likewise.
        * include/bits/hashtable.h
        (_Hashtable<>::__node_builder_t): New.
        (_Hashtable<>::_M_insert_unique<>(_Kt&&, _Arg&&, const _NodeGenerator&)):
         New.
        (_Hashtable<>::_S_forward_key): New.
        (_Hashtable<>::_M_insert): Use latter.
        (_Hashtable<>::_M_insert(const_iterator, _Arg&&, const _NodeGenerator&, false_type)):
        Instantiate node first, compute hash code second.
        * testsuite/23_containers/unordered_map/96088.cc: New test.
        * testsuite/23_containers/unordered_multimap/96088.cc: New test.
        * testsuite/23_containers/unordered_multiset/96088.cc: New test.
        * testsuite/23_containers/unordered_set/96088.cc: New test.
        * testsuite/util/replacement_memory_operators.h
        (counter::_M_increment): New.
        (counter::_M_decrement): New.
        (counter::reset()): New.

2021-05-24  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/100479
        * include/std/ranges (__detail::__non_propagating_cache): Move
        definition up to before that of _CachedPosition.  Make base
        class _Optional_base protected instead of private.  Add const
        overload for operator*.
        (__detail::_CachedPosition): Rewrite the partial specialization
        for forward ranges as a derived class of __non_propagating_cache.
        Remove the size constraint on the partial specialization for
        random access ranges.  Add copy/move/copy-assignment/move-assignment
        members to the offset partial specialization for random
        access ranges that propagate the cached value but additionally
        invalidate it in the source object on move.
        * testsuite/std/ranges/adaptors/100479.cc: New test.

2021-05-24  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/25_algorithms/inplace_merge/constrained.cc: Qualify
        call to ranges::next.
        * testsuite/25_algorithms/is_sorted/constrained.cc: Likewise.
        * testsuite/25_algorithms/is_sorted_until/constrained.cc:
        Likewise.
        * testsuite/25_algorithms/swap_ranges/1.cc: Qualify call to
        swap_ranges.

2021-05-21  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/100606
        * include/std/ranges (drop_while_view::begin): Assert the
        precondition added by LWG 3490.

2021-05-21  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/100690
        * include/std/ranges (iota_view::_Sentinel::_M_distance_from):
        Split out this member function from ...
        (iota_view::_Sentinel::operator-): ... here, for sake of access
        control.
        * testsuite/std/ranges/iota/iota_view.cc (test05): New test.

2021-05-20  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/random.tcc (__representable_as_double)
        (__p1_representable_as_double): Add "" to static asserts.

2021-05-20  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100676
        * include/bits/c++config (__glibcxx_assert_1): Rename to ...
        (__glibcxx_constexpr_assert): ... this.
        (__glibcxx_assert_impl): Use __glibcxx_constexpr_assert.
        (__glibcxx_assert): Define as either __glibcxx_constexpr_assert
        or __glibcxx_assert_impl.
        (__glibcxx_assert_2): Remove
        * include/debug/macros.h (_GLIBCXX_DEBUG_VERIFY_AT_F): Use
        __glibcxx_constexpr_assert instead of __glibcxx_assert_1.
        * testsuite/21_strings/basic_string_view/element_access/char/back_constexpr_neg.cc:
        Adjust expected error.
        * testsuite/21_strings/basic_string_view/element_access/char/constexpr_neg.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/char/front_constexpr_neg.cc:
        Likewise.
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/wchar_t/back_constexpr_neg.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/wchar_t/constexpr_neg.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/wchar_t/front_constexpr_neg.cc:
        Likewise.
        * testsuite/23_containers/span/back_neg.cc: Likewise.
        * testsuite/23_containers/span/front_neg.cc: Likewise.
        * testsuite/23_containers/span/index_op_neg.cc: Likewise.

2021-05-20  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/100639
        * include/bits/stl_iterator.h (reverse_iterator::difference_type):
        In C++20 mode, define in terms of iter_difference_t as per P0896R4.
        (reverse_iterator::reference): Likewise, but with iter_reference_t.
        (reverse_iterator::value_type): Likewise, but with iter_value_t.
        * testsuite/std/ranges/adaptors/reverse.cc (test08): New test.
        * testsuite/24_iterators/reverse_iterator/100639.cc: New test.

2021-05-20  Joern Rennecke  <joern.rennecke@riscy-ip.com>

        PR libstdc++/100361
        * include/std/charconv (to_chars): Hide the overloads for
        floating-point types for 16 bit targets.
        * src/c++17/floating_to_chars.cc: Don't compile for 16 bit targets.
        * testsuite/20_util/to_chars/double.cc: Run this test only on
        size32plus targets.
        * testsuite/20_util/to_chars/float.cc: Likewise.
        * testsuite/20_util/to_chars/long_double.cc: Likewise.

2021-05-18  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/100631
        * include/std/ranges (elements_view::_Sentinel::operator-): Use
        _M_distance_from in the other operator- overload too.
        * testsuite/std/ranges/adaptors/elements.cc (test06): Augment test.

2021-05-18  Thomas Schwinge  <thomas@codesourcery.com>

        * testsuite/lib/prune.exp: Add note about 'dg-note'.

2021-05-18  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/100475
        * include/std/ranges (__box::__box): Use non-list-initialization
        in member initializer list of in-place constructor of the
        partial specialization for semiregular types.
        (__box::operator->): Use std::__addressof.
        * testsuite/std/ranges/adaptors/detail/semiregular_box.cc
        (test02): New test.
        * testsuite/std/ranges/single_view.cc (test04): New test.

2021-05-18  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/100621
        * include/std/ranges (reverse_view::_S_needs_cached_begin):
        Set to true if the underlying non-common random-access range
        doesn't have a sized sentinel.

2021-05-18  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/100631
        * include/std/ranges (elements_view::_Iterator): Also befriend
        _Sentinel<!_Const>.
        (elements_view::_Sentinel::_M_equal): Templatize.
        (elements_view::_Sentinel::_M_distance_from): Split out from ...
        (elements_view::_Sentinel::operator-): ... here.  Depend on
        _Base2 instead of _Base in the return type.
        * testsuite/std/ranges/adaptors/elements.cc (test06, test07):
        New tests.

2021-05-17  Thomas Rodgers  <rodgert@twrodgers.com>

        * include/bits/atomic_wait.h (__waiter::_M_do_wait_v): loop
        until value change observed.
        (__waiter_base::_M_laundered): New member.
        (__waiter_base::_M_notify): Check _M_laundered to determine
        whether to wake one or all.
        (__detail::__atomic_compare): Return true if call to
        __builtin_memcmp() == 0.
        (__waiter_base::_S_do_spin_v): Adjust predicate.
        * testsuite/29_atomics/atomic/wait_notify/100334.cc: New
        test.

2021-05-17  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100630
        * include/experimental/bits/fs_path.h (__is_constructible_from):
        Test construction from a const lvalue, not an rvalue.
        * testsuite/27_io/filesystem/path/construct/100630.cc: New test.
        * testsuite/experimental/filesystem/path/construct/100630.cc:
        New test.

2021-05-17  Antony Polukhin  <antoshkka@gmail.com>

        PR libstdc++/89728
        * include/bits/locale_facets.h (ctype<basic_string<C,T,A>>):
        Declare (but do not define) partial specialization.
        * testsuite/22_locale/ctype/is/string/89728_neg.cc: New test.

2021-05-17  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/thread (jthread::_S_create): Fix static assert
        message.
        * testsuite/30_threads/jthread/95989.cc: Re-enable test.
        * testsuite/30_threads/jthread/jthread.cc: Do not require
        pthread effective target.
        * testsuite/30_threads/jthread/2.cc: Moved to...
        * testsuite/30_threads/jthread/version.cc: ...here.

2021-05-17  Jonathan Wakely  <jwakely@redhat.com>

        * doc/Makefile.am: Simplify doxygen recipes and use --latex_cmd.
        * doc/Makefile.in: Regenerate.
        * doc/doxygen/user.cfg.in (LATEX_CMD_NAME): Add placeholder
        value.
        * scripts/run_doxygen (print_usage): Always print to stdout and
        do not exit.
        (fail): New function for exiting on error.
        (parse_options): Handle --latex_cmd. Do not treat --help the
        same as errors. Simplify handling of required arguments.

2021-05-12  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/25_algorithms/pstl/alg_nonmodifying/find_end.cc:
        Increase dg-timeout-factor to 4. Fix -Wunused-parameter
        warnings. Replace bitwise AND with logical AND in loop
        condition.
        * testsuite/25_algorithms/pstl/alg_nonmodifying/search_n.cc:
        Replace bitwise AND with logical AND in loop condition.
        * testsuite/util/pstl/test_utils.h: Remove unused parameter
        names.

2021-05-11  Patrick Palka  <ppalka@redhat.com>

        * src/c++17/ryu/LOCAL_PATCHES: Update.
        * src/c++17/ryu/ryu_generic_128.h: Remove extern "C".
        Remove declarations for never-defined functions.
        * testsuite/20_util/to_chars/4.cc: New test.

2021-05-11  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/20_util/headers/memory/synopsis.cc: Define C++98
        alternative for macro.
        * testsuite/20_util/shared_ptr/creation/99006.cc: Add effective
        target keyword.
        * testsuite/25_algorithms/copy/debug/99402.cc: Avoid C++11
        syntax.

2021-05-11  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/allocator.h (allocator<void>) [C++20]: Add
        missing noexcept to constructor. Restore missing POCMA and
        is_always_equal_traits.
        [C++17]: Make construct and destroy members private and
        declare allocator_traits as a friend.
        * include/bits/memoryfwd.h (allocator_traits): Declare.
        * include/ext/malloc_allocator.h (malloc_allocator::allocate):
        Add nodiscard attribute. Add static assertion for LWG 3307.
        * include/ext/new_allocator.h (new_allocator::allocate): Add
        static assertion for LWG 3307.
        * testsuite/20_util/allocator/void.cc: Check that converting
        constructor is noexcept. Check for propagation traits and
        size_type and difference_type. Check that pointer and
        const_pointer are gone in C++20.

2021-05-10  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/stop_token: Remove TODO comment.

2021-05-10  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/shared_ptr_base.h (__shared_count(unique_ptr&&)):
        Initialize a non-reference deleter from an rvalue, as per LWG
        3548.
        (__shared_ptr::_UniqCompatible): Add missing constraint.
        * testsuite/20_util/shared_ptr/cons/lwg3548.cc: New test.
        * testsuite/20_util/shared_ptr/cons/unique_ptr_deleter.cc: Check
        constraints.

2021-05-10  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/17_intro/headers/c++2017/all_attributes.cc: Remove
        -std=gnu++17 from dg-options directive.
        * testsuite/17_intro/headers/c++2017/all_no_exceptions.cc:
        Likewise.
        * testsuite/17_intro/headers/c++2017/all_pedantic_errors.cc:
        Likewise.
        * testsuite/17_intro/headers/c++2017/operator_names.cc:
        Likewise.
        * testsuite/17_intro/headers/c++2017/parallel_mode.cc: Likewise.
        * testsuite/17_intro/headers/c++2017/stdc++.cc: Likewise.
        * testsuite/17_intro/headers/c++2017/stdc++_multiple_inclusion.cc:
        Likewise.
        * testsuite/18_support/aligned_alloc/aligned_alloc.cc: Likewise.
        * testsuite/18_support/byte/81076.cc: Likewise.
        * testsuite/18_support/byte/global_neg.cc: Likewise.
        * testsuite/18_support/byte/ops.cc: Likewise.
        * testsuite/18_support/byte/requirements.cc: Likewise.
        * testsuite/18_support/headers/cfloat/values_c++17.cc: Likewise.
        * testsuite/18_support/launder/1.cc: Likewise.
        * testsuite/18_support/launder/nodiscard.cc: Likewise.
        * testsuite/18_support/launder/requirements.cc: Likewise.
        * testsuite/18_support/launder/requirements_neg.cc: Likewise.
        * testsuite/18_support/new_aligned.cc: Likewise.
        * testsuite/18_support/uncaught_exceptions/uncaught_exceptions.cc:
        Likewise.
        * testsuite/19_diagnostics/error_code/is_error_code_v.cc:
        Likewise.
        * testsuite/19_diagnostics/error_condition/hash.cc: Likewise.
        * testsuite/20_util/addressof/requirements/constexpr.cc:
        Likewise.
        * testsuite/20_util/as_const/1.cc: Likewise.
        * testsuite/20_util/as_const/rvalue_neg.cc: Likewise.
        * testsuite/20_util/bind/83427.cc: Likewise.
        * testsuite/20_util/bind/is_placeholder_v.cc: Likewise.
        * testsuite/20_util/bool_constant/requirements.cc: Likewise.
        * testsuite/20_util/duration/arithmetic/constexpr_c++17.cc:
        Likewise.
        * testsuite/20_util/duration/requirements/treat_as_floating_point_v.cc:
        Likewise.
        * testsuite/20_util/duration_cast/rounding.cc: Likewise.
        * testsuite/20_util/enable_shared_from_this/members/weak_from_this.cc:
        Likewise.
        * testsuite/20_util/from_chars/1_neg.cc: Likewise.
        * testsuite/20_util/from_chars/requirements.cc: Likewise.
        * testsuite/20_util/function/91456.cc: Likewise.
        * testsuite/20_util/function/cons/deduction.cc: Likewise.
        * testsuite/20_util/function_objects/83607.cc: Likewise.
        * testsuite/20_util/function_objects/invoke/59768.cc: Likewise.
        * testsuite/20_util/function_objects/mem_fn/80478.cc: Likewise.
        * testsuite/20_util/function_objects/not_fn/1.cc: Likewise.
        * testsuite/20_util/function_objects/not_fn/87538.cc: Likewise.
        * testsuite/20_util/has_unique_object_representations/requirements/explicit_instantiation.cc:
        Likewise.
        * testsuite/20_util/has_unique_object_representations/requirements/typedefs.cc:
        Likewise.
        * testsuite/20_util/has_unique_object_representations/value.cc:
        Likewise.
        * testsuite/20_util/hash/nullptr.cc: Likewise.
        * testsuite/20_util/in_place/requirements.cc: Likewise.
        * testsuite/20_util/is_aggregate/incomplete_neg.cc: Likewise.
        * testsuite/20_util/is_aggregate/requirements/explicit_instantiation.cc:
        Likewise.
        * testsuite/20_util/is_aggregate/requirements/typedefs.cc:
        Likewise.
        * testsuite/20_util/is_aggregate/value.cc: Likewise.
        * testsuite/20_util/is_invocable/83395.cc: Likewise.
        * testsuite/20_util/is_invocable/91456.cc: Likewise.
        * testsuite/20_util/is_invocable/requirements/explicit_instantiation.cc:
        Likewise.
        * testsuite/20_util/is_invocable/requirements/typedefs.cc:
        Likewise.
        * testsuite/20_util/is_invocable/value.cc: Likewise.
        * testsuite/20_util/is_literal_type/deprecated-1z.cc: Likewise.
        * testsuite/20_util/is_nothrow_constructible/94003.cc: Likewise.
        * testsuite/20_util/is_nothrow_invocable/83395.cc: Likewise.
        * testsuite/20_util/is_nothrow_invocable/requirements/explicit_instantiation.cc:
        Likewise.
        * testsuite/20_util/is_nothrow_invocable/requirements/typedefs.cc: Likewise.
        * testsuite/20_util/is_nothrow_invocable/value.cc: Likewise.
        * testsuite/20_util/is_nothrow_swappable/requirements/explicit_instantiation.cc:
        Likewise.
        * testsuite/20_util/is_nothrow_swappable/requirements/typedefs.cc:
        Likewise.
        * testsuite/20_util/is_nothrow_swappable/value.cc: Likewise.
        * testsuite/20_util/is_nothrow_swappable_with/requirements/explicit_instantiation.cc:
        Likewise.
        * testsuite/20_util/is_nothrow_swappable_with/requirements/typedefs.cc:
        Likewise.
        * testsuite/20_util/is_nothrow_swappable_with/value.cc:
        Likewise.
        * testsuite/20_util/is_swappable/requirements/explicit_instantiation.cc:
        Likewise.
        * testsuite/20_util/is_swappable/requirements/typedefs.cc:
        Likewise.
        * testsuite/20_util/is_swappable/value.cc: Likewise.
        * testsuite/20_util/is_swappable_with/requirements/explicit_instantiation.cc:
        Likewise.
        * testsuite/20_util/is_swappable_with/requirements/typedefs.cc:
        Likewise.
        * testsuite/20_util/is_swappable_with/value.cc: Likewise.
        * testsuite/20_util/logical_traits/83134.cc: Likewise.
        * testsuite/20_util/logical_traits/requirements/explicit_instantiation.cc:
        Likewise.
        * testsuite/20_util/logical_traits/requirements/typedefs.cc:
        Likewise.
        * testsuite/20_util/logical_traits/value.cc: Likewise.
        * testsuite/20_util/pair/cons/deduction.cc: Likewise.
        * testsuite/20_util/pair/swap_cxx17.cc: Likewise.
        * testsuite/20_util/ratio/requirements/ratio_equal_v.cc:
        Likewise.
        * testsuite/20_util/reference_wrapper/83427.cc: Likewise.
        * testsuite/20_util/reference_wrapper/deduction.cc: Likewise.
        * testsuite/20_util/shared_ptr/casts/reinterpret.cc: Likewise.
        * testsuite/20_util/shared_ptr/cons/deduction.cc: Likewise.
        * testsuite/20_util/shared_ptr/requirements/weak_type.cc:
        Likewise.
        * testsuite/20_util/time_point/arithmetic/constexpr.cc:
        Likewise.
        * testsuite/20_util/time_point_cast/rounding.cc: Likewise.
        * testsuite/20_util/to_chars/3.cc: Likewise.
        * testsuite/20_util/to_chars/chars_format.cc: Likewise.
        * testsuite/20_util/to_chars/lwg3266.cc: Likewise.
        * testsuite/20_util/to_chars/requirements.cc: Likewise.
        * testsuite/20_util/tuple/78939.cc: Likewise.
        * testsuite/20_util/tuple/apply/1.cc: Likewise.
        * testsuite/20_util/tuple/apply/2.cc: Likewise.
        * testsuite/20_util/tuple/cons/deduction.cc: Likewise.
        * testsuite/20_util/tuple/make_from_tuple/1.cc: Likewise.
        * testsuite/20_util/tuple/make_from_tuple/2.cc: Likewise.
        * testsuite/20_util/tuple/swap_cxx17.cc: Likewise.
        * testsuite/20_util/tuple/tuple_size_v.cc: Likewise.
        * testsuite/20_util/unique_ptr/cons/deduction_neg.cc: Likewise.
        * testsuite/20_util/uses_allocator/requirements/uses_allocator_v.cc:
        Likewise.
        * testsuite/20_util/variable_templates_for_traits.cc: Likewise.
        * testsuite/20_util/void_t/1.cc: Likewise.
        * testsuite/20_util/weak_ptr/cons/deduction.cc: Likewise.
        * testsuite/24_iterators/container_access.cc: Likewise.
        * testsuite/24_iterators/headers/iterator/range_access_c++17.cc:
        Likewise.
        * testsuite/24_iterators/headers/iterator/synopsis_c++17.cc:
        Likewise.
        * testsuite/24_iterators/range_access/range_access_cpp17.cc:
        Likewise.
        * testsuite/24_iterators/range_access/range_access_cpp17_neg.cc:
        Likewise.
        * testsuite/26_numerics/gcd/gcd_neg.cc: Likewise.
        * testsuite/26_numerics/headers/cmath/functions_std_c++17.cc:
        Likewise.
        * testsuite/26_numerics/headers/cmath/hypot.cc: Likewise.
        * testsuite/26_numerics/headers/cmath/special_functions_global.cc:
        Likewise.
        * testsuite/26_numerics/lcm/1.cc: Likewise.
        * testsuite/26_numerics/lcm/lcm_neg.cc: Likewise.
        * testsuite/26_numerics/valarray/deduction.cc: Likewise.
        * testsuite/27_io/basic_ostream/inserters_other/char/lwg2221.cc:
        Likewise.
        * testsuite/27_io/manipulators/standard/char/quoted_sv.cc:
        Likewise.
        * testsuite/27_io/manipulators/standard/wchar_t/quoted_sv.cc:
        Likewise.
        * testsuite/27_io/types/4.cc: Likewise.
        * testsuite/28_regex/basic_regex/ctors/deduction.cc: Likewise.
        * testsuite/libstdc++-prettyprinters/91997.cc: Likewise.
        * testsuite/libstdc++-prettyprinters/cxx17.cc: Likewise.

2021-05-10  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/20_util/function_objects/searchers.cc: Remove
        -std=gnu++17 from dg-options directive.
        * testsuite/20_util/specialized_algorithms/memory_management_tools/1.cc:
        Likewise.
        * testsuite/20_util/specialized_algorithms/memory_management_tools/destroy_neg.cc:
        Likewise.
        * testsuite/20_util/specialized_algorithms/uninitialized_value_construct/94540.cc:
        Likewise.
        * testsuite/20_util/specialized_algorithms/uninitialized_value_construct/94831.cc:
        Likewise.
        * testsuite/20_util/specialized_algorithms/uninitialized_value_construct_n/94540.cc:
        Likewise.
        * testsuite/20_util/specialized_algorithms/uninitialized_value_construct_n/sizes.cc:
        Likewise.
        * testsuite/20_util/unique_ptr/specialized_algorithms/swap_cxx17.cc:
        Likewise.
        * testsuite/25_algorithms/clamp/1.cc: Likewise.
        * testsuite/25_algorithms/clamp/2.cc: Likewise.
        * testsuite/25_algorithms/clamp/constexpr.cc: Likewise.
        * testsuite/25_algorithms/clamp/requirements/explicit_instantiation/1.cc:
        Likewise.
        * testsuite/25_algorithms/clamp/requirements/explicit_instantiation/pod.cc:
        Likewise.
        * testsuite/25_algorithms/for_each/for_each_n.cc: Likewise.
        * testsuite/25_algorithms/for_each/for_each_n_debug.cc:
        Likewise.
        * testsuite/25_algorithms/sample/1.cc: Likewise.
        * testsuite/25_algorithms/sample/2.cc: Likewise.
        * testsuite/25_algorithms/sample/3.cc: Likewise.
        * testsuite/25_algorithms/sample/81221.cc: Likewise.
        * testsuite/25_algorithms/search/searcher.cc: Likewise.
        * testsuite/26_numerics/exclusive_scan/1.cc: Likewise.
        * testsuite/26_numerics/inclusive_scan/1.cc: Likewise.
        * testsuite/26_numerics/reduce/1.cc: Likewise.
        * testsuite/26_numerics/reduce/2.cc: Likewise.
        * testsuite/26_numerics/transform_exclusive_scan/1.cc: Likewise.
        * testsuite/26_numerics/transform_inclusive_scan/1.cc: Likewise.
        * testsuite/26_numerics/transform_reduce/1.cc: Likewise.

2021-05-10  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/23_containers/array/cons/deduction.cc: Remove
        -std=gnu++17 from dg-options directive.
        * testsuite/23_containers/array/cons/deduction_neg.cc: Likewise.
        * testsuite/23_containers/array/element_access/constexpr_c++17.cc:
        Likewise.
        * testsuite/23_containers/array/requirements/constexpr_iter.cc:
        Likewise.
        * testsuite/23_containers/array/specialized_algorithms/swap_cxx17.cc:
        Likewise.
        * testsuite/23_containers/deque/cons/deduction.cc: Likewise.
        * testsuite/23_containers/deque/modifiers/emplace/cxx17_return.cc:
        Likewise.
        * testsuite/23_containers/forward_list/cons/deduction.cc:
        Likewise.
        * testsuite/23_containers/forward_list/modifiers/emplace_cxx17_return.cc:
        Likewise.
        * testsuite/23_containers/list/cons/deduction.cc: Likewise.
        * testsuite/23_containers/list/modifiers/emplace/cxx17_return.cc:
        Likewise.
        * testsuite/23_containers/map/cons/deduction.cc: Likewise.
        * testsuite/23_containers/map/modifiers/extract.cc: Likewise.
        * testsuite/23_containers/map/modifiers/insert/83226.cc:
        Likewise.
        * testsuite/23_containers/map/modifiers/insert_or_assign/1.cc:
        Likewise.
        * testsuite/23_containers/map/modifiers/merge.cc: Likewise.
        * testsuite/23_containers/map/modifiers/try_emplace/1.cc:
        Likewise.
        * testsuite/23_containers/multimap/cons/deduction.cc: Likewise.
        * testsuite/23_containers/multimap/modifiers/extract.cc:
        Likewise.
        * testsuite/23_containers/multimap/modifiers/merge.cc: Likewise.
        * testsuite/23_containers/multiset/cons/deduction.cc: Likewise.
        * testsuite/23_containers/multiset/modifiers/extract.cc:
        Likewise.
        * testsuite/23_containers/multiset/modifiers/merge.cc: Likewise.
        * testsuite/23_containers/priority_queue/deduction.cc: Likewise.
        * testsuite/23_containers/queue/deduction.cc: Likewise.
        * testsuite/23_containers/queue/members/emplace_cxx17_return.cc:
        Likewise.
        * testsuite/23_containers/set/cons/deduction.cc: Likewise.
        * testsuite/23_containers/set/modifiers/extract.cc: Likewise.
        * testsuite/23_containers/set/modifiers/merge.cc: Likewise.
        * testsuite/23_containers/set/modifiers/node_swap.cc: Likewise.
        * testsuite/23_containers/stack/deduction.cc: Likewise.
        * testsuite/23_containers/stack/members/emplace_cxx17_return.cc:
        Likewise.
        * testsuite/23_containers/unordered_map/cons/deduction.cc:
        Likewise.
        * testsuite/23_containers/unordered_map/modifiers/extract.cc:
        Likewise.
        * testsuite/23_containers/unordered_map/modifiers/insert_or_assign.cc:
        Likewise.
        * testsuite/23_containers/unordered_map/modifiers/merge.cc:
        Likewise.
        * testsuite/23_containers/unordered_map/modifiers/try_emplace.cc:
        Likewise.
        * testsuite/23_containers/unordered_multimap/cons/deduction.cc:
        Likewise.
        * testsuite/23_containers/unordered_multimap/modifiers/extract.cc:
        Likewise.
        * testsuite/23_containers/unordered_multimap/modifiers/merge.cc:
        Likewise.
        * testsuite/23_containers/unordered_multiset/cons/deduction.cc:
        Likewise.
        * testsuite/23_containers/unordered_multiset/modifiers/extract.cc:
        Likewise.
        * testsuite/23_containers/unordered_multiset/modifiers/merge.cc:
        Likewise.
        * testsuite/23_containers/unordered_set/cons/deduction.cc:
        Likewise.
        * testsuite/23_containers/unordered_set/modifiers/extract.cc:
        Likewise.
        * testsuite/23_containers/unordered_set/modifiers/merge.cc:
        Likewise.
        * testsuite/23_containers/vector/bool/emplace_cxx17_return.cc:
        Likewise.
        * testsuite/23_containers/vector/cons/89164_c++17.cc: Likewise.
        * testsuite/23_containers/vector/cons/deduction.cc: Likewise.
        * testsuite/23_containers/vector/modifiers/emplace/cxx17_return.cc:
        Likewise.

2021-05-10  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/21_strings/basic_string/79162.cc: Remove
        -std=gnu++17 from dg-options directive.
        * testsuite/21_strings/basic_string/cons/char/7.cc: Likewise.
        * testsuite/21_strings/basic_string/cons/char/79162.cc:
        Likewise.
        * testsuite/21_strings/basic_string/cons/char/86138.cc:
        Likewise.
        * testsuite/21_strings/basic_string/cons/char/9.cc: Likewise.
        * testsuite/21_strings/basic_string/cons/char/deduction.cc:
        Likewise.
        * testsuite/21_strings/basic_string/cons/char/moveable2_c++17.cc:
        Likewise.
        * testsuite/21_strings/basic_string/cons/wchar_t/7.cc: Likewise.
        * testsuite/21_strings/basic_string/cons/wchar_t/79162.cc:
        Likewise.
        * testsuite/21_strings/basic_string/cons/wchar_t/86138.cc:
        Likewise.
        * testsuite/21_strings/basic_string/cons/wchar_t/9.cc: Likewise.
        * testsuite/21_strings/basic_string/cons/wchar_t/deduction.cc:
        Likewise.
        * testsuite/21_strings/basic_string/cons/wchar_t/moveable2_c++17.cc:
        Likewise.
        * testsuite/21_strings/basic_string/hash/hash.cc: Likewise.
        * testsuite/21_strings/basic_string/lwg2758.cc: Likewise.
        * testsuite/21_strings/basic_string/lwg2946.cc: Likewise.
        * testsuite/21_strings/basic_string/modifiers/append/char/4.cc:
        Likewise.
        * testsuite/21_strings/basic_string/modifiers/append/wchar_t/4.cc:
        Likewise.
        * testsuite/21_strings/basic_string/modifiers/assign/char/4.cc:
        Likewise.
        * testsuite/21_strings/basic_string/modifiers/assign/wchar_t/4.cc:
        Likewise.
        * testsuite/21_strings/basic_string/modifiers/insert/char/3.cc:
        Likewise.
        * testsuite/21_strings/basic_string/modifiers/insert/wchar_t/3.cc:
        Likewise.
        * testsuite/21_strings/basic_string/modifiers/replace/char/7.cc:
        Likewise.
        * testsuite/21_strings/basic_string/modifiers/replace/wchar_t/7.cc:
        Likewise.
        * testsuite/21_strings/basic_string/operations/compare/char/2.cc:
        Likewise.
        * testsuite/21_strings/basic_string/operations/compare/wchar_t/2.cc:
        Likewise.
        * testsuite/21_strings/basic_string/operations/data/char/2.cc:
        Likewise.
        * testsuite/21_strings/basic_string/operations/data/char/86169.cc:
        Likewise.
        * testsuite/21_strings/basic_string/operations/data/wchar_t/2.cc:
        Likewise.
        * testsuite/21_strings/basic_string/operations/find/char/5.cc:
        Likewise.
        * testsuite/21_strings/basic_string/operations/find/wchar_t/5.cc:
        Likewise.
        * testsuite/21_strings/basic_string/operators/char/5.cc:
        Likewise.
        * testsuite/21_strings/basic_string/operators/wchar_t/5.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/capacity/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/capacity/empty_neg.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/cons/char/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/cons/char/2.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/cons/char/3.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/cons/char/nonnull.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/cons/wchar_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/cons/wchar_t/2.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/cons/wchar_t/3.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/cons/wchar_t/nonnull.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/char/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/char/2.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/char/back_constexpr_neg.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/char/constexpr.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/char/constexpr_neg.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/char/empty.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/char/front_back.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/char/front_back_constexpr.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/char/front_constexpr_neg.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/wchar_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/wchar_t/2.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/wchar_t/back_constexpr_neg.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/wchar_t/constexpr.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/wchar_t/constexpr_neg.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/wchar_t/empty.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/wchar_t/front_back.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/element_access/wchar_t/front_constexpr_neg.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/include.cc: Likewise.
        * testsuite/21_strings/basic_string_view/inserters/94051.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/inserters/char/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/inserters/char/2.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/inserters/char/3.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/inserters/pod/10081-out.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/inserters/wchar_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/inserters/wchar_t/2.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/inserters/wchar_t/3.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/literals/types-char8_t.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/literals/types.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/literals/values-char8_t.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/literals/values.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/modifiers/remove_prefix/char/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/modifiers/remove_prefix/wchar_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/modifiers/remove_suffix/char/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/modifiers/remove_suffix/wchar_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/modifiers/swap/char/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/modifiers/swap/wchar_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/compare/char/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/compare/char/13650.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/compare/char/2.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/compare/char/70483.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/compare/char/nonnull.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/compare/wchar_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/compare/wchar_t/13650.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/compare/wchar_t/2.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/copy/char/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/copy/char/2.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/copy/wchar_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/copy/wchar_t/2.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/data/char/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/data/wchar_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/find/char/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/find/char/2.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/find/char/3.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/find/char/4.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/find/char/nonnull.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/find/wchar_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/find/wchar_t/2.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/find/wchar_t/3.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/find/wchar_t/4.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/rfind/char/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/rfind/char/2.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/rfind/char/3.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/rfind/char/nonnull.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/rfind/wchar_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/rfind/wchar_t/2.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/rfind/wchar_t/3.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/string_conversion/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/substr/char/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/substr/char/83511.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/substr/wchar_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operations/substr/wchar_t/83511.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operators/char/2.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operators/char/89446.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operators/wchar_t/2.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/operators/wchar_t/89446.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/range_access/char/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/range_access/wchar_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/requirements/explicit_instantiation/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/requirements/explicit_instantiation/char/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/requirements/explicit_instantiation/char16_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/requirements/explicit_instantiation/char32_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/requirements/explicit_instantiation/char8_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/requirements/explicit_instantiation/wchar_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/requirements/traits_neg.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/requirements/typedefs.cc:
        Likewise.
        * testsuite/21_strings/basic_string_view/typedefs.cc: Likewise.
        * testsuite/21_strings/basic_string_view/types/1.cc: Likewise.
        * testsuite/21_strings/char_traits/requirements/char/99181.cc:
        Likewise.
        * testsuite/21_strings/char_traits/requirements/constexpr_functions_c++17.cc:

2021-05-10  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/20_util/memory_resource/1.cc: Remove -std=gnu++17
        from dg-options directive.
        * testsuite/20_util/memory_resource/2.cc: Likewise.
        * testsuite/20_util/monotonic_buffer_resource/1.cc: Likewise.
        * testsuite/20_util/monotonic_buffer_resource/93208.cc:
        Likewise.
        * testsuite/20_util/monotonic_buffer_resource/allocate.cc:
        Likewise.
        * testsuite/20_util/monotonic_buffer_resource/deallocate.cc:
        Likewise.
        * testsuite/20_util/monotonic_buffer_resource/release.cc:
        Likewise.
        * testsuite/20_util/monotonic_buffer_resource/upstream_resource.cc:
        Likewise.
        * testsuite/20_util/polymorphic_allocator/1.cc: Likewise.
        * testsuite/20_util/polymorphic_allocator/construct_pair.cc:
        Likewise.
        * testsuite/20_util/polymorphic_allocator/resource.cc: Likewise.
        * testsuite/20_util/polymorphic_allocator/select.cc: Likewise.
        * testsuite/20_util/synchronized_pool_resource/allocate.cc:
        Likewise.
        * testsuite/20_util/synchronized_pool_resource/allocate_single.cc:
        Likewise.
        * testsuite/20_util/synchronized_pool_resource/cons.cc:
        Likewise.
        * testsuite/20_util/synchronized_pool_resource/cons_single.cc:
        Likewise.
        * testsuite/20_util/synchronized_pool_resource/is_equal.cc:
        Likewise.
        * testsuite/20_util/synchronized_pool_resource/multithreaded.cc:
        Likewise.
        * testsuite/20_util/synchronized_pool_resource/options.cc:
        Likewise.
        * testsuite/20_util/synchronized_pool_resource/release.cc:
        Likewise.
        * testsuite/20_util/synchronized_pool_resource/release_single.cc:
        Likewise.
        * testsuite/20_util/unsynchronized_pool_resource/allocate-max-chunks.cc:
        Likewise.
        * testsuite/20_util/unsynchronized_pool_resource/allocate.cc:
        Likewise.
        * testsuite/20_util/unsynchronized_pool_resource/cons.cc:
        Likewise.
        * testsuite/20_util/unsynchronized_pool_resource/is_equal.cc:
        Likewise.
        * testsuite/20_util/unsynchronized_pool_resource/options.cc:
        Likewise.
        * testsuite/20_util/unsynchronized_pool_resource/release.cc:
        Likewise.
        * testsuite/21_strings/basic_string/types/pmr_typedefs.cc:
        Likewise.
        * testsuite/23_containers/deque/types/pmr_typedefs.cc: Likewise.
        * testsuite/23_containers/deque/types/pmr_typedefs_debug.cc:
        Likewise.
        * testsuite/23_containers/forward_list/pmr_typedefs.cc:
        Likewise.
        * testsuite/23_containers/forward_list/pmr_typedefs_debug.cc:
        Likewise.
        * testsuite/23_containers/list/pmr_typedefs.cc: Likewise.
        * testsuite/23_containers/list/pmr_typedefs_debug.cc: Likewise.
        * testsuite/23_containers/map/pmr_typedefs.cc: Likewise.
        * testsuite/23_containers/map/pmr_typedefs_debug.cc: Likewise.
        * testsuite/23_containers/multimap/pmr_typedefs.cc: Likewise.
        * testsuite/23_containers/multimap/pmr_typedefs_debug.cc:
        Likewise.
        * testsuite/23_containers/multiset/pmr_typedefs.cc: Likewise.
        * testsuite/23_containers/multiset/pmr_typedefs_debug.cc:
        Likewise.
        * testsuite/23_containers/set/pmr_typedefs.cc: Likewise.
        * testsuite/23_containers/set/pmr_typedefs_debug.cc: Likewise.
        * testsuite/23_containers/unordered_map/pmr_typedefs.cc:
        Likewise.
        * testsuite/23_containers/unordered_map/pmr_typedefs_debug.cc:
        Likewise.
        * testsuite/23_containers/unordered_multimap/pmr_typedefs.cc:
        Likewise.
        * testsuite/23_containers/unordered_multimap/pmr_typedefs_debug.cc:
        Likewise.
        * testsuite/23_containers/unordered_multiset/pmr_typedefs.cc:
        Likewise.
        * testsuite/23_containers/unordered_multiset/pmr_typedefs_debug.cc:
        Likewise.
        * testsuite/23_containers/unordered_set/pmr_typedefs.cc:
        Likewise.
        * testsuite/23_containers/unordered_set/pmr_typedefs_debug.cc:
        Likewise.
        * testsuite/23_containers/vector/pmr_typedefs.cc: Likewise.
        * testsuite/23_containers/vector/types/pmr_typedefs_debug.cc:
        Likewise.
        * testsuite/28_regex/match_results/pmr_typedefs.cc: Likewise.

2021-05-10  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/29_atomics/atomic/69769.cc: Remove -std=gnu++17 from
        dg-options.
        * testsuite/29_atomics/atomic/is_always_lock_free.cc:
        * testsuite/29_atomics/atomic/requirements/typedefs.cc:
        * testsuite/29_atomics/atomic_integral/is_always_lock_free.cc:
        * testsuite/29_atomics/atomic_integral/requirements/typedefs.cc:
        * testsuite/30_threads/lock_guard/cons/deduction.cc: Likewise.
        * testsuite/30_threads/scoped_lock/cons/1.cc: Likewise.
        * testsuite/30_threads/scoped_lock/cons/deduction.cc: Likewise.
        * testsuite/30_threads/scoped_lock/requirements/explicit_instantiation.cc:
        Likewise.
        * testsuite/30_threads/scoped_lock/requirements/typedefs.cc:
        Likewise.
        * testsuite/30_threads/shared_lock/70766.cc: Likewise.
        * testsuite/30_threads/shared_mutex/cons/1.cc: Likewise.
        * testsuite/30_threads/shared_mutex/cons/assign_neg.cc:
        Likewise.
        * testsuite/30_threads/shared_mutex/cons/copy_neg.cc: Likewise.
        * testsuite/30_threads/shared_mutex/requirements/standard_layout.cc:
        Likewise.
        * testsuite/30_threads/shared_mutex/try_lock/1.cc: Likewise.
        * testsuite/30_threads/shared_mutex/try_lock/2.cc: Likewise.
        * testsuite/30_threads/shared_mutex/unlock/1.cc: Likewise.
        * testsuite/30_threads/unique_lock/cons/deduction.cc: Likewise.

2021-05-10  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/20_util/any/assign/1.cc: Remove -std=gnu++17 from
        dg-options directive.
        * testsuite/20_util/any/assign/2.cc: Likewise.
        * testsuite/20_util/any/assign/emplace.cc: Likewise.
        * testsuite/20_util/any/assign/exception.cc: Likewise.
        * testsuite/20_util/any/assign/self.cc: Likewise.
        * testsuite/20_util/any/cons/1.cc: Likewise.
        * testsuite/20_util/any/cons/2.cc: Likewise.
        * testsuite/20_util/any/cons/90415.cc: Likewise.
        * testsuite/20_util/any/cons/92156.cc: Likewise.
        * testsuite/20_util/any/cons/aligned.cc: Likewise.
        * testsuite/20_util/any/cons/explicit.cc: Likewise.
        * testsuite/20_util/any/cons/in_place.cc: Likewise.
        * testsuite/20_util/any/cons/nontrivial.cc: Likewise.
        * testsuite/20_util/any/make_any.cc: Likewise.
        * testsuite/20_util/any/misc/any_cast.cc: Likewise.
        * testsuite/20_util/any/misc/any_cast_neg.cc: Likewise.
        * testsuite/20_util/any/misc/any_cast_no_rtti.cc: Likewise.
        * testsuite/20_util/any/misc/swap.cc: Likewise.
        * testsuite/20_util/any/modifiers/1.cc: Likewise.
        * testsuite/20_util/any/modifiers/83658.cc: Likewise.
        * testsuite/20_util/any/modifiers/92156.cc: Likewise.
        * testsuite/20_util/any/observers/type.cc: Likewise.
        * testsuite/20_util/any/requirements.cc: Likewise.
        * testsuite/20_util/any/typedefs.cc: Likewise.
        * testsuite/20_util/optional/77288.cc: Likewise.
        * testsuite/20_util/optional/84601.cc: Likewise.
        * testsuite/20_util/optional/assignment/1.cc: Likewise.
        * testsuite/20_util/optional/assignment/2.cc: Likewise.
        * testsuite/20_util/optional/assignment/3.cc: Likewise.
        * testsuite/20_util/optional/assignment/4.cc: Likewise.
        * testsuite/20_util/optional/assignment/5.cc: Likewise.
        * testsuite/20_util/optional/assignment/6.cc: Likewise.
        * testsuite/20_util/optional/assignment/7.cc: Likewise.
        * testsuite/20_util/optional/assignment/8.cc: Likewise.
        * testsuite/20_util/optional/assignment/9.cc: Likewise.
        * testsuite/20_util/optional/bad_access.cc: Likewise.
        * testsuite/20_util/optional/cons/77727.cc: Likewise.
        * testsuite/20_util/optional/cons/85642.cc: Likewise.
        * testsuite/20_util/optional/cons/copy.cc: Likewise.
        * testsuite/20_util/optional/cons/deduction.cc: Likewise.
        * testsuite/20_util/optional/cons/default.cc: Likewise.
        * testsuite/20_util/optional/cons/move.cc: Likewise.
        * testsuite/20_util/optional/cons/trivial.cc: Likewise.
        * testsuite/20_util/optional/cons/value.cc: Likewise.
        * testsuite/20_util/optional/cons/value_neg.cc: Likewise.
        * testsuite/20_util/optional/constexpr/cons/default.cc:
        Likewise.
        * testsuite/20_util/optional/constexpr/cons/value.cc: Likewise.
        * testsuite/20_util/optional/constexpr/in_place.cc: Likewise.
        * testsuite/20_util/optional/constexpr/make_optional.cc:
        Likewise.
        * testsuite/20_util/optional/constexpr/nullopt.cc: Likewise.
        * testsuite/20_util/optional/constexpr/observers/1.cc: Likewise.
        * testsuite/20_util/optional/constexpr/observers/2.cc: Likewise.
        * testsuite/20_util/optional/constexpr/observers/3.cc: Likewise.
        * testsuite/20_util/optional/constexpr/observers/4.cc: Likewise.
        * testsuite/20_util/optional/constexpr/observers/5.cc: Likewise.
        * testsuite/20_util/optional/constexpr/relops/1.cc: Likewise.
        * testsuite/20_util/optional/constexpr/relops/2.cc: Likewise.
        * testsuite/20_util/optional/constexpr/relops/3.cc: Likewise.
        * testsuite/20_util/optional/constexpr/relops/4.cc: Likewise.
        * testsuite/20_util/optional/constexpr/relops/5.cc: Likewise.
        * testsuite/20_util/optional/constexpr/relops/6.cc: Likewise.
        * testsuite/20_util/optional/hash.cc: Likewise.
        * testsuite/20_util/optional/in_place.cc: Likewise.
        * testsuite/20_util/optional/make_optional.cc: Likewise.
        * testsuite/20_util/optional/nullopt.cc: Likewise.
        * testsuite/20_util/optional/observers/1.cc: Likewise.
        * testsuite/20_util/optional/observers/2.cc: Likewise.
        * testsuite/20_util/optional/observers/3.cc: Likewise.
        * testsuite/20_util/optional/observers/4.cc: Likewise.
        * testsuite/20_util/optional/observers/5.cc: Likewise.
        * testsuite/20_util/optional/observers/6.cc: Likewise.
        * testsuite/20_util/optional/relops/1.cc: Likewise.
        * testsuite/20_util/optional/relops/2.cc: Likewise.
        * testsuite/20_util/optional/relops/3.cc: Likewise.
        * testsuite/20_util/optional/relops/4.cc: Likewise.
        * testsuite/20_util/optional/relops/5.cc: Likewise.
        * testsuite/20_util/optional/relops/6.cc: Likewise.
        * testsuite/20_util/optional/relops/7.cc: Likewise.
        * testsuite/20_util/optional/requirements.cc: Likewise.
        * testsuite/20_util/optional/swap/1.cc: Likewise.
        * testsuite/20_util/optional/swap/2.cc: Likewise.
        * testsuite/20_util/optional/typedefs.cc: Likewise.
        * testsuite/20_util/variant/80165.cc: Likewise.
        * testsuite/20_util/variant/85183.cc: Likewise.
        * testsuite/20_util/variant/86874.cc: Likewise.
        * testsuite/20_util/variant/87431.cc: Likewise.
        * testsuite/20_util/variant/87619.cc: Likewise.
        * testsuite/20_util/variant/91807.cc: Likewise.
        * testsuite/20_util/variant/any.cc: Likewise.
        * testsuite/20_util/variant/compile.cc: Likewise.
        * testsuite/20_util/variant/deduction.cc: Likewise.
        * testsuite/20_util/variant/exception_safety.cc: Likewise.
        * testsuite/20_util/variant/hash.cc: Likewise.
        * testsuite/20_util/variant/index_type.cc: Likewise.
        * testsuite/20_util/variant/relops/89851.cc: Likewise.
        * testsuite/20_util/variant/relops/90008.cc: Likewise.
        * testsuite/20_util/variant/run.cc: Likewise.
        * testsuite/20_util/variant/visit.cc: Likewise.

2021-05-10  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/27_io/basic_filebuf/open/char/path.cc: Remove
        -std=gnu++17 from dg-options directive.
        * testsuite/27_io/basic_fstream/cons/char/path.cc: Likewise.
        * testsuite/27_io/basic_fstream/open/char/path.cc: Likewise.
        * testsuite/27_io/basic_ifstream/cons/char/path.cc: Likewise.
        * testsuite/27_io/basic_ifstream/open/char/path.cc: Likewise.
        * testsuite/27_io/basic_ofstream/cons/char/path.cc: Likewise.
        * testsuite/27_io/basic_ofstream/open/char/path.cc: Likewise.
        * testsuite/27_io/filesystem/directory_entry/86597.cc: Likewise.
        * testsuite/27_io/filesystem/directory_entry/lwg3171.cc:
        Likewise.
        * testsuite/27_io/filesystem/file_status/1.cc: Likewise.
        * testsuite/27_io/filesystem/filesystem_error/cons.cc: Likewise.
        * testsuite/27_io/filesystem/filesystem_error/copy.cc: Likewise.
        * testsuite/27_io/filesystem/iterators/91067.cc: Likewise.
        * testsuite/27_io/filesystem/iterators/caching.cc: Likewise.
        * testsuite/27_io/filesystem/iterators/directory_iterator.cc:
        Likewise.
        * testsuite/27_io/filesystem/iterators/pop.cc: Likewise.
        * testsuite/27_io/filesystem/iterators/recursion_pending.cc:
        Likewise.
        * testsuite/27_io/filesystem/iterators/recursive_directory_iterator.cc:
        Likewise.
        * testsuite/27_io/filesystem/operations/absolute.cc: Likewise.
        * testsuite/27_io/filesystem/operations/all.cc: Likewise.
        * testsuite/27_io/filesystem/operations/canonical.cc: Likewise.
        * testsuite/27_io/filesystem/operations/copy.cc: Likewise.
        * testsuite/27_io/filesystem/operations/copy_file.cc: Likewise.
        * testsuite/27_io/filesystem/operations/create_directories.cc:
        Likewise.
        * testsuite/27_io/filesystem/operations/create_directory.cc:
        Likewise.
        * testsuite/27_io/filesystem/operations/create_symlink.cc:
        Likewise.
        * testsuite/27_io/filesystem/operations/current_path.cc:
        Likewise.
        * testsuite/27_io/filesystem/operations/equivalent.cc: Likewise.
        * testsuite/27_io/filesystem/operations/exists.cc: Likewise.
        * testsuite/27_io/filesystem/operations/file_size.cc: Likewise.
        * testsuite/27_io/filesystem/operations/is_empty.cc: Likewise.
        * testsuite/27_io/filesystem/operations/last_write_time.cc:
        Likewise.
        * testsuite/27_io/filesystem/operations/permissions.cc:
        Likewise.
        * testsuite/27_io/filesystem/operations/proximate.cc: Likewise.
        * testsuite/27_io/filesystem/operations/read_symlink.cc:
        Likewise.
        * testsuite/27_io/filesystem/operations/relative.cc: Likewise.
        * testsuite/27_io/filesystem/operations/remove.cc: Likewise.
        * testsuite/27_io/filesystem/operations/remove_all.cc: Likewise.
        * testsuite/27_io/filesystem/operations/rename.cc: Likewise.
        * testsuite/27_io/filesystem/operations/resize_file.cc:
        Likewise.
        * testsuite/27_io/filesystem/operations/space.cc: Likewise.
        * testsuite/27_io/filesystem/operations/status.cc: Likewise.
        * testsuite/27_io/filesystem/operations/symlink_status.cc:
        Likewise.
        * testsuite/27_io/filesystem/operations/temp_directory_path.cc:
        Likewise.
        * testsuite/27_io/filesystem/operations/weakly_canonical.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/append/path.cc: Likewise.
        * testsuite/27_io/filesystem/path/append/source.cc: Likewise.
        * testsuite/27_io/filesystem/path/assign/assign.cc: Likewise.
        * testsuite/27_io/filesystem/path/assign/copy.cc: Likewise.
        * testsuite/27_io/filesystem/path/compare/compare.cc: Likewise.
        * testsuite/27_io/filesystem/path/compare/lwg2936.cc: Likewise.
        * testsuite/27_io/filesystem/path/compare/path.cc: Likewise.
        * testsuite/27_io/filesystem/path/compare/strings.cc: Likewise.
        * testsuite/27_io/filesystem/path/concat/92853.cc: Likewise.
        * testsuite/27_io/filesystem/path/concat/94063.cc: Likewise.
        * testsuite/27_io/filesystem/path/concat/path.cc: Likewise.
        * testsuite/27_io/filesystem/path/concat/strings.cc: Likewise.
        * testsuite/27_io/filesystem/path/construct/80762.cc: Likewise.
        * testsuite/27_io/filesystem/path/construct/90281.cc: Likewise.
        * testsuite/27_io/filesystem/path/construct/90634.cc: Likewise.
        * testsuite/27_io/filesystem/path/construct/copy.cc: Likewise.
        * testsuite/27_io/filesystem/path/construct/default.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/construct/format.cc: Likewise.
        * testsuite/27_io/filesystem/path/construct/locale.cc: Likewise.
        * testsuite/27_io/filesystem/path/construct/range.cc: Likewise.
        * testsuite/27_io/filesystem/path/construct/string_view.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/decompose/extension.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/decompose/filename.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/decompose/parent_path.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/decompose/relative_path.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/decompose/root_directory.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/decompose/root_name.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/decompose/root_path.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/decompose/stem.cc: Likewise.
        * testsuite/27_io/filesystem/path/factory/u8path-char8_t.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/factory/u8path.cc: Likewise.
        * testsuite/27_io/filesystem/path/generation/normal.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/generation/normal2.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/generation/proximate.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/generation/relative.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/generic/94242.cc: Likewise.
        * testsuite/27_io/filesystem/path/generic/generic_string.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/generic/utf.cc: Likewise.
        * testsuite/27_io/filesystem/path/generic/wchar_t.cc: Likewise.
        * testsuite/27_io/filesystem/path/io/dr2989.cc: Likewise.
        * testsuite/27_io/filesystem/path/itr/components.cc: Likewise.
        * testsuite/27_io/filesystem/path/itr/traversal.cc: Likewise.
        * testsuite/27_io/filesystem/path/modifiers/clear.cc: Likewise.
        * testsuite/27_io/filesystem/path/modifiers/make_preferred.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/modifiers/remove_filename.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/modifiers/replace_extension.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/modifiers/replace_filename.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/modifiers/swap.cc: Likewise.
        * testsuite/27_io/filesystem/path/native/alloc.cc: Likewise.
        * testsuite/27_io/filesystem/path/native/string-char8_t.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/native/string.cc: Likewise.
        * testsuite/27_io/filesystem/path/nonmember/append.cc: Likewise.
        * testsuite/27_io/filesystem/path/nonmember/cmp.cc: Likewise.
        * testsuite/27_io/filesystem/path/nonmember/hash_value.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/query/empty.cc: Likewise.
        * testsuite/27_io/filesystem/path/query/empty_neg.cc:
        * testsuite/27_io/filesystem/path/query/has_extension.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/query/has_filename.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/query/has_parent_path.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/query/has_relative_path.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/query/has_root_directory.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/query/has_root_name.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/query/has_root_path.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/query/has_stem.cc: Likewise.
        * testsuite/27_io/filesystem/path/query/is_absolute.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/query/is_relative.cc:
        Likewise.
        * testsuite/experimental/filesystem/path/construct/string_view.cc:
        Likewise.

2021-05-10  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/20_util/specialized_algorithms/pstl/uninitialized_construct.cc:
        Remove -std=gnu++17 from dg-options.
        * testsuite/20_util/specialized_algorithms/pstl/uninitialized_copy_move.cc:
        Likewise.
        * testsuite/20_util/specialized_algorithms/pstl/uninitialized_fill_destroy.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_merge/inplace_merge.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_merge/merge.cc: Likewise.
        * testsuite/25_algorithms/pstl/alg_modifying_operations/copy_if.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_modifying_operations/copy_move.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_modifying_operations/fill.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_modifying_operations/generate.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_modifying_operations/is_partitioned.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_modifying_operations/partition.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_modifying_operations/partition_copy.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_modifying_operations/remove.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_modifying_operations/remove_copy.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_modifying_operations/replace.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_modifying_operations/replace_copy.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_modifying_operations/rotate.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_modifying_operations/rotate_copy.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_modifying_operations/swap_ranges.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_modifying_operations/transform_binary.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_modifying_operations/transform_unary.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_modifying_operations/unique.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_modifying_operations/unique_copy_equal.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_nonmodifying/adjacent_find.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_nonmodifying/all_of.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_nonmodifying/any_of.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_nonmodifying/count.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_nonmodifying/equal.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_nonmodifying/find.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_nonmodifying/find_end.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_nonmodifying/find_first_of.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_nonmodifying/find_if.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_nonmodifying/for_each.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_nonmodifying/mismatch.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_nonmodifying/none_of.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_nonmodifying/nth_element.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_nonmodifying/reverse.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_nonmodifying/reverse_copy.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_nonmodifying/search_n.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_sorting/includes.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_sorting/is_heap.cc: Likewise.
        * testsuite/25_algorithms/pstl/alg_sorting/is_sorted.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_sorting/lexicographical_compare.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_sorting/minmax_element.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_sorting/partial_sort.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_sorting/partial_sort_copy.cc:
        Likewise.
        * testsuite/25_algorithms/pstl/alg_sorting/set.cc: Likewise.
        * testsuite/25_algorithms/pstl/alg_sorting/sort.cc: Likewise.
        * testsuite/25_algorithms/pstl/feature_test-2.cc: Likewise.
        * testsuite/25_algorithms/pstl/feature_test-3.cc: Likewise.
        * testsuite/25_algorithms/pstl/feature_test-4.cc: Likewise.
        * testsuite/25_algorithms/pstl/feature_test-5.cc: Likewise.
        * testsuite/25_algorithms/pstl/feature_test.cc: Likewise.
        * testsuite/26_numerics/pstl/numeric_ops/adjacent_difference.cc:
        Likewise.
        * testsuite/26_numerics/pstl/numeric_ops/reduce.cc: Likewise.
        * testsuite/26_numerics/pstl/numeric_ops/scan.cc: Likewise.
        * testsuite/26_numerics/pstl/numeric_ops/transform_reduce.cc:
        Likewise.
        * testsuite/26_numerics/pstl/numeric_ops/transform_scan.cc:
        Likewise.

2021-05-10  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/20_util/scoped_allocator/69293_neg.cc: Add dg-error
        for additional errors in C++20.
        * testsuite/20_util/specialized_algorithms/memory_management_tools/destroy_neg.cc:
        Likewise.
        * testsuite/20_util/uses_allocator/69293_neg.cc: Likewise.
        * testsuite/27_io/filesystem/path/io/dr2989.cc: Likewise.

2021-05-10  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/20_util/variant/compile.cc: Rename 'any' to avoid
        clash with std::any.

2021-05-07  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/istream (__rvalue_stream_extraction_t): Replace
        use of __rval_streamable.
        * include/std/ostream (__rvalue_stream_insertion_t): Likewise.
        (__rval_streamable): Remove.
        (_Require_derived_from_ios_base, __derived_from_ios_base): New
        helper for checking constraints.
        * testsuite/27_io/basic_istream/extractors_other/char/4.cc: Fix
        reference to the wrong subclause of the standard.
        * testsuite/27_io/basic_istream/extractors_other/wchar_t/4.cc:
        Likewise.
        * testsuite/27_io/basic_ostream/inserters_other/char/6.cc:
        Likewise.
        * testsuite/27_io/basic_ostream/inserters_other/wchar_t/6.cc:
        Likewise.
        * testsuite/27_io/basic_ostream/inserters_other/char/99692.cc:
        New test.
        * testsuite/27_io/filesystem/path/io/dr2989.cc: Adjust pruned
        errors.

2021-05-06  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/stl_algobase.h (__copy_move, __copy_move_backward):
        Improve static_assert messages.
        * testsuite/25_algorithms/copy/58982.cc: Adjust expected output.
        * testsuite/25_algorithms/copy_n/58982.cc: Likewise.

2021-05-06  Patrick Palka  <ppalka@redhat.com>

        * include/std/ranges (filter_view::_Iterator::base): Make the
        const& overload unconstrained and return a const reference as
        per LWG 3533.  Make unconditionally noexcept.
        (transform_view::_Iterator::base): Likewise.
        (elements_view::_Iterator::base): Likewise.

2021-05-06  Patrick Palka  <ppalka@redhat.com>

        * include/bits/stl_iterator.h (move_iterator::base): Make the
        const& overload unconstrained and return a const reference as
        per LWG 3391.  Make unconditionally noexcept.
        (counted_iterator::base): Likewise.
        * testsuite/24_iterators/move_iterator/lwg3391.cc: New test.
        * testsuite/24_iterators/move_iterator/move_only.cc: Adjust
        has_member_base concept to decay-copy the result of base().

2021-05-06  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/type_traits (remove_cvref_t): Define in terms of
        remove_cvref.
        * testsuite/20_util/remove_cvref/value.cc: Check alias.

2021-05-06  Jonathan Wakely  <jwakely@redhat.com>

        Revert:
        2021-05-05  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/charconv (__from_chars_alnum): Pass unsigned
        char to std::isdigit.

2021-05-05  Patrick Palka  <ppalka@redhat.com>

        * include/bits/ranges_util.h (enable_borrowed_range<subrange>):
        Remove constraints on this partial specialization.
        * include/std/ranges (enable_borrowed_range<iota_view>):
        Likewise.

2021-05-05  Patrick Palka  <ppalka@redhat.com>

        * include/std/ranges (transform_view::_Iterator::iter_swap):
        Remove as per LWG 3520.
        (join_view::_Iterator::iter_swap): Add indirectly_swappable
        constraint as per LWG 3517.

2021-05-05  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/20_util/function_objects/invoke/3.cc: Check feature
        test macro.
        * testsuite/20_util/function_objects/invoke/version.cc: New test.

2021-05-05  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/charconv (__from_chars_alnum): Pass unsigned
        char to std::isdigit.

2021-05-05  Corentin Gay  <gay@adacore.com>

        * acinclude.m4: Add VxWorks-specific case for the
        configuration of ctypes.
        * configure: Regenerate.
        * config/locale/vxworks/ctype_members.cc: Add VxWorks-specific
        version.
        * config/os/vxworks/ctype_base.h: Adjust for VxWorks7+.
        * config/os/vxworks/ctype_configure_char.cc: Likewise.
        * config/os/vxworks/ctype_inline.h: Likewise.
        * testsuite/28_regex/traits/char/isctype.cc: Defines
        NEWLINE_IN_CLASS_BLANK if the target is VxWorks.
        * testsuite/28_regex/traits/wchar_t/isctype.cc: Likewise.

2021-05-04  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/future (promise::set_value): Check for existence
        of shared state before dereferncing it.
        (promise::set_exception, promise::set_value_at_thread_exit)
        (promise::set_exception_at_thread_exit): Likewise.
        (promise<R&>::set_value, promise<R&>::set_exception)
        (promise<R&>::set_value_at_thread_exit)
        (promise<R&>::set_exception_at_thread_exit): Likewise.
        (promise<void>::set_value, promise<void>::set_exception)
        (promise<void>::set_value_at_thread_exit)
        (promise<void>::set_exception_at_thread_exit): Likewise.
        * testsuite/30_threads/promise/members/at_thread_exit2.cc:
        Remove unused variable.

2021-05-04  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/basic_string.h (basic_string(const CharT*, const A&)):
        Do not do arithmetic on null pointer.

2021-05-04  Jonathan Wakely  <jwakely@redhat.com>

        * include/ext/pb_ds/detail/cc_hash_table_map_/cc_ht_map_.hpp
        (find_key_pointer(key_const_reference, false_type))
        (find_key_pointer(key_const_reference, true_type)): Do not
        dereference null pointer.

2021-05-04  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/20_util/from_chars/3.cc: Use unsigned type to avoid
        overflow.
        * testsuite/24_iterators/reverse_iterator/2.cc: Do not add
        non-zero value to null pointer.
        * testsuite/25_algorithms/copy_backward/move_iterators/69478.cc:
        Use past-the-end iterator for result.
        * testsuite/25_algorithms/move_backward/69478.cc: Likewise.
        * testsuite/25_algorithms/move_backward/93872.cc: Likewise.

2021-05-04  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100384
        * include/std/variant (__get_t): New alias template yielding the
        return type of std::get<N> on a variant.
        (__visit_result_t): New alias template yielding the result of
        std::visit.
        (__same_types): Move into namespace __detail::__variant.
        (__check_visitor_results): Likewise. Use __invoke_result_t and
        __get_t.
        (__check_visitor_result): Remove.
        (visit): Use __visit_result_t for return type.
        * testsuite/20_util/variant/100384.cc: New test.

2021-05-04  Jonathan Wakely  <jwakely@redhat.com>

        * acinclude.m4 (GLIBCXX_ENABLE_INT128_FLOAT128): Remove
        checks for __int128 and rename to GLIBCXX_ENABLE_FLOAT128.
        * config.h.in: Regenerate.
        * configure: Regenerate.
        * configure.ac: Adjust to use GLIBCXX_ENABLE_FLOAT128.
        * include/bits/random.h (_Select_uint_least_t<s, 1>):
        Use __SIZEOF_INT128__ to decide whether to use __int128.
        * include/std/charconv (__to_chars_unsigned_type): Likewise.

2021-05-03  Gerald Pfeifer  <gerald@pfeifer.com>

        * doc/xml/manual/ctype.xml: Move unix.org reference to https.
        * doc/html/manual/facets.html: Regenerate.

2021-04-30  Patrick Palka  <ppalka@redhat.com>

        * include/std/ranges (__detail::__non_propating_cache): Define
        as per P2328.
        (join_view): Remove constraints on the value and reference types
        of the wrapped iterator type as per P2328.
        (join_view::_Iterator::_M_satisfy): Adjust as per P2328.
        (join_view::_Iterator::operator++): Likewise.
        (join_view::_M_inner): Use __non_propating_cache as per P2328.
        Remove now-redundant use of __maybe_present_t.
        * testsuite/std/ranges/adaptors/join.cc: Include <array>.
        (test10): New test.

2021-04-30  Jonathan Wakely  <jwakely@redhat.com>

        * 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  Jonathan Wakely  <jwakely@redhat.com>

        * acinclude.m4 (GLIBCXX_CHECK_INT64_T): Delete.
        * config.h.in: Regenerate.
        * configure: Regenerate.
        * configure.ac: Do not use GLIBCXX_CHECK_INT64_T.
        * include/bits/postypes.h: Remove include of <stdint.h> and
        definition/undefinition of the __STDC_LIMIT_MACROS and
        __STDC_CONSTANT_MACROS macros.
        (streamoff): Use __INT64_TYPE__ if defined.

2021-04-30  Patrick Palka  <ppalka@redhat.com>

        * include/std/ranges (split_view::_InnerIter::operator++):
        Depend on _Base instead of _Vp directly, as per LWG 3532.

2021-04-30  Patrick Palka  <ppalka@redhat.com>

        * include/bits/ranges_util.h (subrange::subrange): Avoid
        list-initialization in delegating constructor.
        * include/std/ranges (single_view): Replace implicit guide
        with explicit deduction guide that decays its argument.
        (_Single::operator()): Avoid CTAD when constructing the
        single_view object.
        (_Iota::operator()): Avoid list-initialization.
        (__detail::__can_filter_view, _Filter::operator()): Likewise.
        (__detail::__can_transform_view, _Transform::operator()): Likewise.
        (take_view::begin): Likewise.
        (__detail::__can_take_view, _Take::operator()): Likewise.
        (__detail::__can_take_while_view, _TakeWhile::operator()): Likewise.
        (__detail::__can_drop_view, _Drop::operator()): Likewise.
        (__detail::__can_drop_while_view, _DropWhile::operator()): Likewise.
        (split_view::split_view): Use views::single when initializing
        _M_pattern.
        (__detail::__can_split_view, _Split::operator()): Avoid
        list-initialization.
        (_Counted::operator()): Likewise.
        * testsuite/std/ranges/p2367.cc: New test.

2021-04-30  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/60497
        * include/bits/basic_ios.tcc (basic_ios::copyfmt): use
        std::addressof.
        * include/bits/basic_string.tcc (basic_string::swap)
        (basic_string::assign): Likewise.
        * include/bits/deque.tcc (deque::operator=(const deque&)):
        Likewise.
        * include/bits/stl_tree.h (_Rb_tree::operator=(const * _Rb_tree&)):
        Likewise.
        * include/bits/vector.tcc (vector::operator=(const vector&)):
        Likewise.

2021-04-30  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/istream (operator>>(Istream&&, x&)): Simplify, as
        per LWG 1203.
        * include/std/ostream (operator<<(Ostream&&, const x&)):
        Likewise.
        * testsuite/27_io/basic_istream/extractors_character/char/lwg2499_neg.cc:
        Adjust dg-error pattern.
        * testsuite/27_io/basic_istream/extractors_character/wchar_t/lwg2499_neg.cc:
        Likewise.
        * testsuite/27_io/basic_istream/extractors_other/char/4.cc: Define
        is_extractable trait to replace std::__is_extractable. Make it
        work with rvalue streams as well as lvalues, to replace f() and
        g() helper functions.
        * testsuite/27_io/basic_istream/extractors_other/wchar_t/4.cc:
        Likewise.
        * testsuite/27_io/basic_ostream/inserters_other/char/6.cc:
        Define is_insertable trait to replace std::__is_insertable. Make
        it work with rvalue streams as well as lvalues, to replace f()
        and g() helper functions.
        * testsuite/27_io/basic_ostream/inserters_other/wchar_t/6.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/io/dr2989.cc: Prune additional
        errors from new constraints.
        * testsuite/27_io/rvalue_streams-2.cc: Remove PR 80675 checks,
        which are no longer expected to compile.
        * testsuite/27_io/rvalue_streams.cc: Adjust existing test.
        Verify LWG 1203 changes.

2021-04-30  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100285
        * include/experimental/socket (__basic_socket_impl::set_option)
        (__basic_socket_impl::get_option) [!_GLIBCXX_HAVE_SYS_SOCKET_H]:
        Just set error code.
        * testsuite/experimental/net/socket/socket_base.cc: CHeck
        for <sys/socket.h> not <socket.h>.

2021-04-30  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100180
        PR libstdc++/100286
        PR libstdc++/100351
        * testsuite/experimental/net/internet/address/v4/comparisons.cc:
        Use new effective-target keyword.
        * testsuite/experimental/net/internet/address/v4/cons.cc:
        Likewise.
        * testsuite/experimental/net/internet/address/v4/creation.cc:
        Likewise.
        * testsuite/experimental/net/internet/address/v4/members.cc:
        Likewise.
        * testsuite/experimental/net/internet/address/v6/members.cc:
        Likewise.
        * testsuite/experimental/net/internet/resolver/base.cc:
        Likewise.
        * testsuite/experimental/net/internet/resolver/ops/lookup.cc:
        Likewise.
        * testsuite/experimental/net/internet/resolver/ops/reverse.cc:
        Likewise.
        * testsuite/experimental/net/internet/socket/opt.cc:
        Likewise.
        * testsuite/experimental/net/internet/tcp.cc:
        Likewise.
        * testsuite/experimental/net/internet/udp.cc:
        Likewise.
        * testsuite/lib/libstdc++.exp (check_effective_target_net_ts_ip):
        New proc to check net_ts_ip et.

2021-04-28  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/97930
        * testsuite/20_util/pair/requirements/structural.cc: New test.

2021-04-28  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/stl_pair.h (pair) [__cplusplus > 202002]: Add
        new definitions for constructors and assignment operators using
        concepts for constraints.
        * testsuite/20_util/pair/cons/99957.cc: Disable for C++20 and
        later.
        * testsuite/20_util/pair/cons/explicit_construct.cc: Adjust
        expected error messages to also match C++20 errors.

2021-04-28  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99957
        * include/bits/stl_pair.h (_PCC::_MoveCopyPair, _PCC::_CopyMovePair):
        Combine and replace with ...
        (_PCC::_DeprConsPair): New SFINAE helper function.
        (pair): Merge preprocessor blocks so that all C++03 members
        are defined together at the end.
        (pair::pair(const _T1&, _U2&&), pair::pair(_U1&&, const _T2&)):
        Replace _T1 and _T2 parameters with __null_ptr_constant and
        adjust constraints.
        * testsuite/20_util/pair/40925.cc: Use nullptr instead of 0.
        * testsuite/20_util/pair/cons/explicit_construct.cc: Likewise.
        * testsuite/20_util/pair/cons/99957.cc: New test.

2021-04-28  Jonathan Wakely  <jwakely@redhat.com>

        * 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  Jonathan Wakely  <jwakely@redhat.com>

        * doc/Makefile.am (stamp-pdf-doxygen): Improve comment about
        dealing with errors. Use '@' to prevent shell command being
        echoed.
        * doc/Makefile.in: Regenerate.

2021-04-28  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100298
        * include/bits/std_thread.h (thread::hardware_concurrency): Add
        missing noexcept to inline definition for non-gthreads targets.

2021-04-28  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/100187
        PR libstdc++/100237
        PR libstdc++/100249
        PR libstdc++/100287
        * include/bits/ranges_algo.h (__search_n_fn::operator()): Give
        the __value_comp lambda an explicit bool return type.
        (__is_permutation_fn::operator()): Give the __proj_scan local
        variable auto&& return type.  Give the __comp_scan lambda an
        explicit bool return type.
        (__remove_fn::operator()): Give the __pred lambda an explicit
        bool return type.
        (__partition_fn::operator()): Don't std::move __first twice
        when returning an empty subrange.
        (__min_fn::operator()): Don't std::move __comp.
        (__max_fn::operator()): Likewise.
        (__minmax_fn::operator()): Likewise.

2021-04-27  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/100290
        * include/std/ranges (join_view::_Iterator::operator++): Correct
        the return type of the lambda to avoid returning a copy of
        _M_parent->_M_inner.
        * testsuite/std/ranges/adaptors/join.cc (test10): New test.

2021-04-27  Jakub Jelinek  <jakub@redhat.com>

        Revert:
        2021-04-22  Jakub Jelinek  <jakub@redhat.com>

        PR target/100182
        * testsuite/29_atomics/atomic_float/1.cc: Add dg-xfail-run-if for
        ia32.
        * testsuite/29_atomics/atomic_float/wait_notify.cc: Add dg-skip-if for
        ia32.

2021-04-27  Jonathan Wakely  <jwakely@redhat.com>

        * include/experimental/internet (address_v6::bytes_type): Adjust
        formatting.
        (basic_endpoint): Define _M_is_v6() to put all checks for
        AF_INET6 in one place.
        (basic_endpoint::resize): Simplify.
        (operator==(const tcp&, const tcp&)): Add constexpr and noexcept.
        (operator!=(const tcp&, const tcp&)): Likewise.
        (operator==(const udp&, const udp&)): Likewise.
        (operator!=(const udp&, const udp&)): Likewise.
        * testsuite/experimental/net/internet/tcp.cc: New test.
        * testsuite/experimental/net/internet/udp.cc: New test.

2021-04-27  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100286
        * include/experimental/internet (resolver_errc, resolver_category())
        (make_error_code, make_error_condition): Define unconditionally,
        only make enumerators and use of gai_strerror depend on the
        availability of <netdb.h>.
        (address_v4::to_string): Use correct constant for string length.
        (address_v4::to_string, address_v6::to_string): Define
        unconditionally, throw if unsupported.
        (make_address_v4, make_address_v6): Define unconditionally.
        Return an error if unsupported.
        (tcp, udp, v6_only, unicast::hops, multicast::*): Define
        conditionally,
        * testsuite/experimental/net/internet/socket/opt.cc: Check for
        <netinet/in.h> and <netinet/tcp.h> before using types from
        namespace net::ip.

2021-04-27  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100285
        * include/experimental/internet (resolver_base::flags):
        Define overloaded operators as hidden friends.
        * include/experimental/socket (socket_base::message_flags):
        Likewise.

2021-04-26  Jonathan Wakely  <jwakely@redhat.com>

        * include/experimental/internet (tcp::no_delay, v6_only)
        (unicast::hops, multicast::hops, multicast::enable_loopback):
        Change access of base class and static data members. Add
        using-declaration for __socket_crtp::operator=(_Tp).
        (multicast::__mcastopt): New type.
        (multicast::join_group, multicast::leave_group): Derive from
        __mcastopt for common implementation.
        * include/experimental/socket: Add comment.
        * testsuite/experimental/net/internet/socket/opt.cc: New test.
        * testsuite/experimental/net/socket/socket_base.cc: Check for
        protected constructor/destructor of socket_base. Check for
        explicit constructors of socket option classes.

2021-04-26  Jonathan Wakely  <jwakely@redhat.com>

        * include/experimental/bits/net.h (__socket_base): Add
        bool template parameter to allow BooleanSocketOption and
        IntegerSocketOption to have different __socket_base<int>
        base classes.
        (__socket_base<bool>): Adjust base class.
        (__socket_base<int>): Add partial specialization.
        (__socket_crtp::operator=(_Tp)): Add noexcept-specifier.
        * include/experimental/socket (socket_base::broadcast)
        (socket_base::debug, socket_base::do_not_route)
        (socket_base::keep_alive, socket_base::linger)
        (socket_base::out_of_band_inline)
        (socket_base::receive_buffer_size)
        (socket_base::receive_low_watermark)
        (socket_base::reuse_address, socket_base::send_buffer_size)
        (socket_base::send_low_watermark): Add using-declaration for
        __socket_crtp::operator=(_Tp).
        * testsuite/experimental/net/socket/socket_base.cc: Check
        properties of socket option types.

2021-04-26  Jonathan Wakely  <jwakely@redhat.com>

        * include/experimental/internet (resolver_base::flags): Remove
        enumerators. Initialize constants directly with desired values.
        Make all operators constexpr and noexcept.
        * testsuite/experimental/net/internet/resolver/base.cc: Use
        __gnu_test::test_bitmask_values for bitmask type. Check
        construction and destruction is protected.

2021-04-26  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/semaphore_base.h: Include <exception> and <errno.h>.

2021-04-26  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100259
        * include/experimental/internet (net::ip::make_error_code)
        (net::ip::make_error_condition, net::ip::make_network_v4)
        (net::ip::operator==(const udp&, const udp&)): Add 'inline'.

2021-04-24  David Edelsohn  <dje.gcc@gmail.com>

        * testsuite/lib/dg-options.exp (atomic_link_flags): New.
        (add_options_for_libatomic): Use atomic_link_flags.

2021-04-23  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100180
        * include/experimental/io_context (io_context): Define
        dummy_pollfd type so that most member functions still compile
        without <poll.h> and struct pollfd.

2021-04-23  Jonathan Wakely  <jwakely@redhat.com>

        * include/experimental/io_context (io_context::async_wait): Add
        comment.
        * include/experimental/socket (basic_socket::async_connect):
        Cast wait_type constant to int.
        (basic_datagram_socket::async_receive): Likewise.
        (basic_datagram_socket::async_receive_from): Likewise.
        (basic_datagram_socket::async_send): Likewise.
        (basic_datagram_socket::async_send_to): Likewise.
        (basic_stream_socket::async_receive): Likewise.
        (basic_stream_socket::async_send): Likewise. Use io_context
        parameter directly, instead of via an executor.
        (basic_socket_acceptor::async_accept): Likewise.

2021-04-23  Jonathan Wakely  <jwakely@redhat.com>

        * include/experimental/socket (socket_base::shutdown_type):
        (socket_base::wait_type, socket_base::message_flags):
        Remove enumerators. Initialize constants directly with desired
        values.
        (socket_base::message_flags): Make all operators constexpr and
        noexcept.
        * testsuite/util/testsuite_common_types.h (test_bitmask_values):
        New test utility.
        * testsuite/experimental/net/socket/socket_base.cc: New test.

2021-04-22  David Edelsohn  <dje.gcc@gmail.com>

        * config/os/aix/atomicity.h: Delete.

2021-04-22  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/atomic_timed_wait.h (__cond_wait_until_impl):
        Handle system_clock as well as steady_clock.
        * testsuite/30_threads/semaphore/try_acquire_for.cc: Re-enable.
        * testsuite/30_threads/semaphore/try_acquire_until.cc:
        Re-enable.

2021-04-22  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/30_threads/semaphore/try_acquire_posix.cc: Add
        options for libatomic.

2021-04-22  Jonathan Wakely  <jwakely@redhat.com>

        * config/os/gnu-linux/os_defines.h: Fix type in comment.

2021-04-22  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99006
        * include/bits/shared_ptr.h (allocate_shared): Assert that _Tp
        is not an array type.
        * include/bits/shared_ptr_base.h (__allocate_shared): Likewise.
        * testsuite/20_util/shared_ptr/creation/99006.cc: New test.

2021-04-22  Thomas Rodgers  <rodgert@twrodgers.com>

        * include/bits/atomic_wait.h: Always notify waiters in the
        case of 'bare' address notification.

2021-04-22  Jakub Jelinek  <jakub@redhat.com>

        PR target/100182
        * testsuite/29_atomics/atomic_float/1.cc: Add dg-xfail-run-if for
        ia32.
        * testsuite/29_atomics/atomic_float/wait_notify.cc: Add dg-skip-if for
        ia32.

2021-04-22  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100179
        * include/bits/semaphore_base.h: Remove #error.
        * include/std/semaphore: Do not define anything unless one of
        the implementations is available.

2021-04-21  Thomas Rodgers  <rodgert@twrodgers.com>

        * include/bits/semaphore_base.h: Always reload __old in
        __atomic_semaphore::_S_do_try_acquire().
        * testsuite/30_threads/stop_token/stop_callback/destroy.cc:
        re-enable testcase.

2021-04-21  Philippe Blain  <levraiphilippeblain@gmail.com>
            Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99453
        * python/Makefile.am: Install libstdc++*-gdb.py more robustly.
        * python/Makefile.in: Regenerate.

2021-04-21  Thomas Rodgers  <rodgert@twrodgers.com>

        * include/bits/semaphore_base.h: Add missing _M_try_acquire()
        member to __platform_wait.

2021-04-21  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/latch: Replace tab characters in license text.
        * include/std/semaphore: Likewise.

2021-04-21  Jakub Jelinek  <jakub@redhat.com>

        PR libstdc++/100164
        * acinclude.m4: For POSIX semaphores AC_DEFINE HAVE_POSIX_SEMAPHORE
        rather than _GLIBCXX_HAVE_POSIX_SEMAPHORE.
        * configure: Regenerated.
        * config.h.in: Regenerated.

2021-04-20  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/30_threads/semaphore/try_acquire_for.cc: Disable
        test for targets not using futexes for semaphores.
        * testsuite/30_threads/semaphore/try_acquire_until.cc: Likewise.
        * testsuite/30_threads/stop_token/stop_callback/destroy.cc:
        Disable for all targets.

2021-04-20  Thomas Rodgers  <trodgers@redhat.com>

        * include/Makefile.am: Add new <bits/this_thread_sleep.h> header.
        * include/Makefile.in: Regenerate.
        * include/bits/this_thread_sleep.h: New file.
        * include/bits/atomic_base.h: Adjust all calls
        to __atomic_wait/__atomic_notify for new call signatures.
        * include/bits/atomic_timed_wait.h: Extensive rewrite.
        * include/bits/atomic_wait.h: Likewise.
        * include/bits/semaphore_base.h: Adjust all calls
        to __atomic_wait/__atomic_notify for new call signatures.
        * include/std/atomic: Likewise.
        * include/std/barrier: Likewise.
        * include/std/latch: Likewise.
        * include/std/semaphore: Likewise.
        * include/std/thread (this_thread::sleep_for)
        (this_thread::sleep_until): Move to new header.
        * testsuite/29_atomics/atomic/wait_notify/bool.cc: Simplify
        test.
        * testsuite/29_atomics/atomic/wait_notify/generic.cc: Likewise.
        * testsuite/29_atomics/atomic/wait_notify/pointers.cc: Likewise.
        * 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.

2021-04-20  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/95983
        * include/bits/stl_iterator.h (__detail::__move_iter_cat):
        Define.
        (move_iterator): Derive from the above in C++20 in order to
        conditionally define iterator_category as per P2259.
        (move_iterator::__base_cat): No longer used, so remove.
        (move_iterator::iterator_category): Remove in C++20.
        (__detail::__common_iter_use_postfix_proxy): Define.
        (common_iterator::_Proxy): Rename to ...
        (common_iterator:__arrow_proxy): ... this.
        (common_iterator::__postfix_proxy): Define as per P2259.
        (common_iterator::operator->): Adjust.
        (common_iterator::operator++): Adjust as per P2259.
        (iterator_traits<common_iterator>::_S_iter_cat): Define.
        (iterator_traits<common_iterator>::iterator_category): Change as
        per P2259.
        (__detail::__counted_iter_value_type): Define.
        (__detail::__counted_iter_concept): Define.
        (__detail::__counted_iter_cat): Define.
        (counted_iterator): Derive from the above three classes in order
        to conditionally define value_type, iterator_concept and
        iterator category respectively as per P2259.
        (counted_iterator::operator->): Define as per P2259.
        (incrementable_traits<counted_iterator>): Remove as per P2259.
        (iterator_traits<counted_iterator>): Adjust as per P2259.
        * include/std/ranges (__detail::__iota_view_iter_cat): Define.
        (iota_view::_Iterator): Derive from the above in order to
        conditionally define iterator_category as per P2259.
        (iota_view::_S_iter_cat): Rename to ...
        (iota_view::_S_iter_concept): ... this.
        (iota_view::iterator_concept): Use it to apply LWG 3291 changes.
        (iota_view::iterator_category): Remove.
        (__detail::__filter_view_iter_cat): Define.
        (filter_view::_Iterator): Derive from the above in order to
        conditionally define iterator_category as per P2259.
        (filter_view::_Iterator): Move to struct __filter_view_iter_cat.
        (filter_view::_Iterator::iterator_category): Remove.
        (transform_view::_Base): Define.
        (transform_view::__iter_cat): Define.
        (transform_view::_Iterator): Derive from the above in order to
        conditionally define iterator_category as per P2259.
        (transform_view::_Iterator::_Base): Just alias
        transform_view::_Base.
        (transform_view::_Iterator::_S_iter_cat): Move to struct
        transform_view::__iter_cat.
        (transform_view::_Iterator::iterator_category): Remove.
        (transform_view::_Sentinel::_Base): Just alias
        transform_view::_Base.
        (join_view::_Base): Define.
        (join_view::_Outer_iter): Define.
        (join_view::_Inner_iter): Define.
        (join_view::_S_ref_is_glvalue): Define.
        (join_view::__iter_cat): Define.
        (join_view::_Iterator): Derive from it in order to conditionally
        define iterator_category as per P2259.
        (join_view::_Iterator::_Base): Just alias join_view::_Base.
        (join_view::_Iterator::_S_ref_is_glvalue): Just alias
        join_view::_S_ref_is_glvalue.
        (join_view::_Iterator::_S_iter_cat): Move to struct
        transform_view::__iter_cat.
        (join_view::_Iterator::_Outer_iter): Just alias
        join_view::_Outer_iter.
        (join_view::_Iterator::_Inner_iter): Just alias
        join_view::_Inner_iter.
        (join_view::_Iterator::iterator_category): Remove.
        (join_view::_Sentinel::_Base): Just alias join_view::_Base.
        (__detail::__split_view_outer_iter_cat): Define.
        (__detail::__split_view_inner_iter_cat): Define.
        (split_view::_Base): Define.
        (split_view::_Outer_iter): Derive from __split_view_outer_iter_cat
        in order to conditionally define iterator_category as per P2259.
        (split_view::_Outer_iter::iterator_category): Remove.
        (split_view::_Inner_iter): Derive from __split_view_inner_iter_cat
        in order to conditionally define iterator_category as per P2259.
        (split_view::_Inner_iter::_S_iter_cat): Move to
        __split_view_inner_iter_cat.
        (split_view::_Inner_iter::iterator_category): Remove.
        (elements_view::_Base): Define.
        (elements_view::__iter_cat): Define.
        (elements_view::_Iterator): Derive from the above in order to
        conditionall define iterator_category as per P2259.
        (elements_view::_Iterator::_Base): Just alias
        elements_view::_Base.
        (elements_view::_Iterator::_S_iter_concept)
        (elements_view::_Iterator::iterator_concept): Define as per
        P2259.
        (elements_view::_Iterator::iterator_category): Remove.
        (elements_view::_Sentinel::_Base): Just alias
        elements_view::_Base.
        * testsuite/24_iterators/headers/iterator/synopsis_c++20.cc:
        Adjust constraints on iterator_traits<counted_iterator>.
        * testsuite/std/ranges/p2259.cc: New test.

2021-04-20  Jonathan Wakely  <jwakely@redhat.com>

        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  Jakub Jelinek  <jakub@redhat.com>

        * testsuite/util/testsuite_abi.cc (compare_symbols): If any symbol
        versions with _IEEE128_ substring are found, set ieee_version_found
        to true.  Ignore missing symbols with _IEEE128_ in version name if
        !ieee_version_found.  Use i->first as version_name instead of
        i->second.version_name if the latter is empty.
        * config/abi/post/powerpc64-linux-gnu/baseline_symbols.txt: Update.

2021-04-19  H.J. Lu  <hjl.tools@gmail.com>

        * config/abi/post/x86_64-linux-gnu/x32/baseline_symbols.txt:
        Updated.

2021-04-17  Jakub Jelinek  <jakub@redhat.com>

        * config/abi/post/powerpc-linux-gnu/baseline_symbols.txt: Update.
        * config/abi/post/powerpc64-linux-gnu/32/baseline_symbols.txt: Update.

2021-04-17  Jakub Jelinek  <jakub@redhat.com>

        * config/abi/post/x86_64-linux-gnu/baseline_symbols.txt: Update.
        * config/abi/post/x86_64-linux-gnu/32/baseline_symbols.txt: Update.
        * config/abi/post/i386-linux-gnu/baseline_symbols.txt: Update.
        * config/abi/post/i486-linux-gnu/baseline_symbols.txt: Update.
        * config/abi/post/s390x-linux-gnu/baseline_symbols.txt: Update.
        * config/abi/post/powerpc64-linux-gnu/baseline_symbols.txt: Update.

2021-04-15  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/lib/dg-options.exp (add_options_for_libatomic): Also
        add libatomic options for 32-bit sparc*-*-linux-gnu.

2021-04-15  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/96657
        * libsupc++/Makefile.am: Add atomicity.cc here.
        * src/c++98/Makefile.am: Remove it from here.
        * libsupc++/Makefile.in: Regenerate.
        * src/c++98/Makefile.in: Regenerate.
        * testsuite/18_support/exception_ptr/96657.cc: New test.

2021-04-13  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100060
        * include/std/bit: Only include <ext/numeric_traits.h> for
        hosted build, use <limits> otherwise.

2021-04-13  Jonathan Wakely  <jwakely@redhat.com>

        * doc/xml/manual/backwards_compatibility.xml: Remove porting
        notes for libg++ and libstdc++-v2, and bibliography.
        * doc/html/*: Regenerated.

2021-04-12  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/100044
        * include/bits/ranges_util.h (__detail::__iterator_sentinel_pair):
        Remove helper concept.
        (subrange(_Pr), subrange(Pr, __make_unsigned_like<...>)): Remove
        deduction guides, as per LWG 3404.
        * testsuite/std/ranges/subrange/lwg3282_neg.cc: Check that class
        template argument deduction fails.

2021-04-12  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/26_numerics/random/linear_congruential_engine/requirements/non_uint_neg.cc:
        Adjust expected error for C++20 mode.
        * testsuite/tr1/5_numerical_facilities/random/linear_congruential/requirements/non_uint_neg.cc:
        Likewise.

2021-04-12  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99995
        * testsuite/17_intro/headers/c++1998/49745.cc: Include all
        standard headers and XFAIL for effective-target c++20.

2021-04-09  François Dumont  <fdumont@gcc.gnu.org>

        PR libstdc++/99402
        * include/debug/helper_functions.h (__can_advance(_InputIterator,
        const std::pair<_Diff, _Distance_precision>&, int)): New.
        (__can_advance(const _Safe_iterator<>&,
        const std::pair<_Diff, _Distance_precision>&, int)): New.
        * include/debug/macros.h (__glibcxx_check_can_increment_dist): New,
        use latter.
        (__glibcxx_check_can_increment_range): Adapt to use latter.
        (__glibcxx_check_can_decrement_range): Likewise.
        * include/debug/safe_iterator.h
        (_Safe_iterator<>::_M_can_advance(const std::pair<_Diff, _Distance_precision>&,
        int)): New.
        (__can_advance(const _Safe_iterator<>&,
        const std::pair<_Diff, _Distance_precision>&, int)): New.
        * include/debug/safe_iterator.tcc
        (_Safe_iterator<>::_M_can_advance(const std::pair<_Diff, _Distance_precision>&,
        int)): New.
        (_Safe_iterator<>::_M_valid_range(const _Safe_iterator<>&,
        std::pair<difference_type, _Distance_precision>&, bool)): Adapt for
        __dp_sign_max_size.
        (__copy_move_a): Adapt to use __glibcxx_check_can_increment_dist.
        (__copy_move_backward_a): Likewise.
        (__equal_aux): Likewise.
        * include/debug/stl_iterator.h (__can_advance(const std::reverse_iterator<>&,
        const std::pair<_Diff, _Distance_precision>&, int)): New.
        (__can_advance(const std::move_iterator<>&,
        const std::pair<_Diff, _Distance_precision>&, int)): New.
        * testsuite/25_algorithms/copy/debug/99402.cc: New test.

2021-04-09  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99985
        * include/bits/hashtable.h (_Hashtable::_S_nothrow_move()): Fix
        to be a valid constexpr function in C++11.
        * testsuite/23_containers/unordered_set/cons/99985.cc: New test.

2021-04-09  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/fs_fwd.h: Fix doxygen group command.
        * include/bits/streambuf_iterator.h: Likewise.
        * include/bits/uses_allocator_args.h: Likewise.
        * include/std/memory: Likewise.
        * include/tr1/complex: Likewise.

2021-04-08  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/basic_string.h: Tweak doxygen comment.

2021-04-08  Patrick Palka  <ppalka@redhat.com>

        * include/std/ranges (__detail::find): Define.
        (split_view::_OuterIter::operator++): Apply proposed resolution
        of LWG 3505.
        * testsuite/std/ranges/adaptors/split.cc (test10): New test.

2021-04-08  Patrick Palka  <ppalka@redhat.com>

        * include/std/ranges (__detail::find_if): Simplify.
        (__detail::find_if_not): Likewise.
        (__detail::min): Remove.
        (__detail::mismatch): Simplify.
        (take_view::size): Use std::min instead of __detail::min.

2021-04-08  Patrick Palka  <ppalka@redhat.com>

        * include/std/ranges (__detail::__returnable_element): New
        concept.
        (elements_view): Use this concept in its constraints.  Add
        missing private access specifier.
        (elements_view::_S_get_element): Define as per LWG 3502.
        (elements_view::operator*, elements_view::operator[]): Use
        _S_get_element.
        (elements_view::operator++): Remove unnecessary constraint
        as per LWG 3492.
        * testsuite/std/ranges/adaptors/elements.cc (test05): New test.

2021-04-08  Jonathan Wakely  <jwakely@redhat.com>

        * doc/Makefile.am (stamp-pdf-doxygen): Also grep for
        out-of-memory error in log file.
        * doc/Makefile.in: Regenerate.

2021-04-08  Jonathan Wakely  <jwakely@redhat.com>

        * configure: Regenerate.

2021-04-08  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/random.h: Fix doxygen group commands.
        * include/bits/regex_constants.h: Likewise.
        * include/tr1/random.h: Likewise.

2021-04-08  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/hashtable.h (_Hashtable::_S_nothrow_move()):
        New function to determine noexcept-specifier for move
        constructors.
        (_Hashtable): Use _S_nothrow_move() on move constructors.
        * testsuite/23_containers/unordered_map/cons/noexcept_move_construct.cc:
        Correct static assertion message.
        * testsuite/23_containers/unordered_multimap/cons/noexcept_move_construct.cc:
        Likewise.
        * testsuite/23_containers/unordered_multiset/cons/noexcept_move_construct.cc:
        Likewise.
        * testsuite/23_containers/unordered_set/cons/noexcept_move_construct.cc:
        Likewise.

2021-04-08  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/98384
        * testsuite/20_util/to_chars/long_double.cc: Don't run the test
        on targets without a large long double.  XFAIL the execution on
        targets with a non-conforming printf.

2021-04-08  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/99433
        * include/std/ranges (__adaptor::__maybe_refwrap): Remove.
        (__adaptor::__adaptor_invocable): New concept.
        (__adaptor::__adaptor_partial_app_viable): New concept.
        (__adaptor::_RangeAdaptorClosure): Rewrite, turning it into a
        non-template base class.
        (__adaptor::_RangeAdaptor): Rewrite, turning it into a CRTP base
        class template.
        (__adaptor::_Partial): New class template that represents
        partial application of a range adaptor non-closure.
        (__adaptor::__pipe_invocable): New concept.
        (__adaptor::_Pipe): New class template.
        (__detail::__can_ref_view): New concept.
        (__detail::__can_subrange): New concept.
        (all): Replace the lambda here with ...
        (_All): ... this functor.  Add appropriate constraints.
        (__detail::__can_filter_view): New concept.
        (filter, _Filter): As in all/_All.
        (__detail::__can_transform): New concept.
        (transform, _Transform): As in all/_All.
        (__detail::__can_take_view): New concept.
        (take, _Take): As in all/_All.
        (__detail::__can_take_while_view): New concept.
        (take_while, _TakeWhile): As in all/_All.
        (__detail::__can_drop_view): New concept.
        (drop, _Drop): As in all/_All.
        (__detail::__can_drop_while_view): New concept.
        (drop_while, _DropWhile): As in all/_All.
        (__detail::__can_join_view): New concept.
        (join, _Join): As in all/_All.
        (__detail::__can_split_view): New concept.
        (split, _Split): As in all/_All.  Rename template parameter
        _Fp to _Pattern.
        (__detail::__already_common): New concept.
        (__detail::__can_common_view): New concept.
        (common, _Common): As in all/_All.
        (__detail::__can_reverse_view): New concept.
        (reverse, _Reverse): As in all/_All.
        (__detail::__can_elements_view): New concept.
        (elements, _Elements): As in all/_All.
        (keys, values): Adjust.
        * testsuite/std/ranges/adaptors/99433.cc: New test.
        * testsuite/std/ranges/adaptors/all.cc: No longer expect that
        adding empty range adaptor closure objects to a pipeline doesn't
        increase the size of the pipeline.
        (test05): New test.
        * testsuite/std/ranges/adaptors/common.cc (test03): New test.
        * testsuite/std/ranges/adaptors/drop.cc (test09): New test.
        * testsuite/std/ranges/adaptors/drop_while.cc (test04): New test.
        * testsuite/std/ranges/adaptors/elements.cc (test04): New test.
        * testsuite/std/ranges/adaptors/filter.cc (test06): New test.
        * testsuite/std/ranges/adaptors/join.cc (test09): New test.
        * testsuite/std/ranges/adaptors/p2281.cc: New test.
        * testsuite/std/ranges/adaptors/reverse.cc (test07): New test.
        * testsuite/std/ranges/adaptors/split.cc (test01, test04):
        Adjust.
        (test09): New test.
        * testsuite/std/ranges/adaptors/split_neg.cc (test01): Adjust
        expected error message.
        (test02): Likewise.  Extend test.
        * testsuite/std/ranges/adaptors/take.cc (test06): New test.
        * testsuite/std/ranges/adaptors/take_while.cc (test05): New test.
        * testsuite/std/ranges/adaptors/transform.cc (test07, test08):
        New test.

2021-04-08  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/string_view: Adjust Doxygen @file comment.

2021-04-08  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/type_traits (is_scoped_enum<T>): Constrain partial
        specialization to not match incomplete enum types. Use a
        requires-expression instead of instantiating is_convertible.
        (is_scoped_enum<const T>): Add as workaround for PR c++/99968.
        * testsuite/20_util/is_scoped_enum/value.cc: Check with
        incomplete types and opaque-enum-declarations.

2021-04-07  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99805
        * src/c++17/fs_path.cc (path::_M_split_cmpts): Do not call
        non-const member on _M_pathname, to avoid copy-on-write.
        * testsuite/27_io/filesystem/path/decompose/parent_path.cc:
        Check construction from strings that might be shared.

2021-04-06  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/move.h (forward, move, move_if_noexcept)
        (addressof): Add _GLIBCXX_NODISCARD.
        * include/bits/ranges_cmp.h (identity::operator()): Add
        nodiscard attribute.
        * include/c_global/cstddef (to_integer): Likewise.
        * include/std/bit (bit_cast): Likewise.
        * include/std/utility (as_const, to_underlying): Likewise.

2021-04-06  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/move.h (forward): Change static_assert message
        to be unambiguous about what must be true.
        * testsuite/20_util/forward/c_neg.cc: Adjust dg-error.
        * testsuite/20_util/forward/f_neg.cc: Likewise.

2021-04-06  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/alloc_traits.h: Use markdown for code font.
        * include/bits/basic_string.h: Fix @param names.
        * include/bits/max_size_type.h: Remove period after @file.
        * include/bits/regex.h: Fix duplicate @retval names, and rename.
        * include/ext/pb_ds/detail/priority_queue_base_dispatch.hpp: Add
        group open to match existing group close.
        * include/ext/pb_ds/priority_queue.hpp: Add blank line before group
        open.

2021-04-06  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/atomic_base.h: Fix doxygen group close.
        * include/bits/basic_ios.h: Likewise.
        * include/bits/forward_list.h: Likewise.
        * include/bits/fs_dir.h: Likewise.
        * include/bits/fs_ops.h: Likewise.
        * include/bits/fs_path.h: Likewise.
        * include/bits/functional_hash.h: Likewise.
        * include/bits/gslice.h: Likewise.
        * include/bits/gslice_array.h: Likewise.
        * include/bits/hashtable_policy.h: Likewise.
        * include/bits/indirect_array.h: Likewise.
        * include/bits/locale_classes.h: Likewise.
        * include/bits/locale_facets.h: Likewise.
        * include/bits/locale_facets_nonio.h: Likewise.
        * include/bits/mask_array.h: Likewise.
        * include/bits/refwrap.h: Likewise.
        * include/bits/regex.h: Likewise.
        * include/bits/regex_automaton.h: Likewise.
        * include/bits/regex_compiler.h: Likewise.
        * include/bits/regex_constants.h: Likewise.
        * include/bits/regex_error.h: Likewise.
        * include/bits/regex_executor.h: Likewise.
        * include/bits/regex_scanner.h: Likewise.
        * include/bits/shared_ptr.h: Likewise.
        * include/bits/shared_ptr_atomic.h: Likewise.
        * include/bits/shared_ptr_base.h: Likewise.
        * include/bits/slice_array.h: Likewise.
        * include/bits/specfun.h: Likewise.
        * include/bits/std_function.h: Likewise.
        * include/bits/std_mutex.h: Likewise.
        * include/bits/stl_deque.h: Likewise.
        * include/bits/stl_iterator.h: Likewise.
        * include/bits/stl_iterator_base_types.h: Likewise.
        * include/bits/stl_map.h: Likewise.
        * include/bits/stl_multimap.h: Likewise.
        * include/bits/stl_multiset.h: Likewise.
        * include/bits/stl_numeric.h: Likewise.
        * include/bits/stl_pair.h: Likewise.
        * include/bits/stl_set.h: Likewise.
        * include/bits/stl_uninitialized.h: Likewise.
        * include/bits/stream_iterator.h: Likewise.
        * include/bits/streambuf_iterator.h: Likewise.
        * include/bits/unique_ptr.h: Likewise.
        * include/bits/unordered_map.h: Likewise.
        * include/bits/unordered_set.h: Likewise.
        * include/decimal/decimal: Likewise.
        * include/experimental/any: Likewise.
        * include/experimental/array: Likewise.
        * include/experimental/bits/fs_dir.h: Likewise.
        * include/experimental/bits/fs_fwd.h: Likewise.
        * include/experimental/bits/fs_ops.h: Likewise.
        * include/experimental/bits/fs_path.h: Likewise.
        * include/experimental/buffer: Likewise.
        * include/experimental/internet: Likewise.
        * include/experimental/optional: Likewise.
        * include/experimental/propagate_const: Likewise.
        * include/experimental/socket: Likewise.
        * include/ext/pb_ds/assoc_container.hpp: Likewise.
        * include/ext/pb_ds/detail/priority_queue_base_dispatch.hpp:
        Likewise.
        * include/ext/pb_ds/detail/tree_policy/node_metadata_selector.hpp: Likewise.
        * include/ext/pb_ds/detail/trie_policy/node_metadata_selector.hpp: Likewise.
        * include/ext/pb_ds/detail/types_traits.hpp: Likewise.
        * include/ext/pb_ds/exception.hpp: Likewise.
        * include/ext/pb_ds/priority_queue.hpp: Likewise.
        * include/ext/pb_ds/tag_and_trait.hpp: Likewise.
        * include/ext/random: Likewise.
        * include/std/any: Likewise.
        * include/std/atomic: Likewise.
        * include/std/bitset: Likewise.
        * include/std/chrono: Likewise.
        * include/std/complex: Likewise.
        * include/std/condition_variable: Likewise.
        * include/std/fstream: Likewise.
        * include/std/future: Likewise.
        * include/std/iostream: Likewise.
        * include/std/istream: Likewise.
        * include/std/mutex: Likewise.
        * include/std/numeric: Likewise.
        * include/std/ostream: Likewise.
        * include/std/ratio: Likewise.
        * include/std/shared_mutex: Likewise.
        * include/std/stdexcept: Likewise.
        * include/std/streambuf: Likewise.
        * include/std/system_error: Likewise.
        * include/std/thread: Likewise.
        * include/std/valarray: Likewise.
        * include/std/variant: Likewise.
        * include/tr1/cmath: Likewise.
        * include/tr1/regex: Likewise.
        * include/tr2/dynamic_bitset: Likewise.
        * libsupc++/atomic_lockfree_defines.h: Likewise.
        * libsupc++/exception: Likewise.
        * libsupc++/exception.h: Likewise.
        * libsupc++/exception_ptr.h: Likewise.
        * libsupc++/nested_exception.h: Likewise.

2021-03-31  Alexandre Oliva  <oliva@adacore.com>

        * testsuite/30_threads/future/members/poll.cc: Use faster
        after-ready call in the calibration loop.

2021-03-29  Jonathan Wakely  <jwakely@redhat.com>

        * doc/xml/manual/status_cxx2017.xml: Adjust link for PSTL.
        * doc/html/manual/status.html: Regenerate.

2021-03-28  François Dumont  <fdumont@gcc.gnu.org>

        * include/debug/forward_list
        (forward_list(forward_list&&, const allocator_type&)): Add noexcept qualification.
        * include/debug/list (list(list&&, const allocator_type&)): Likewise and add
        call to safe container allocator aware move constructor.
        * include/debug/vector (vector(vector&&, const allocator_type&)):
        Fix noexcept qualification.
        * testsuite/23_containers/forward_list/cons/noexcept_move_construct.cc:
        Add allocator-extended move constructor noexceot qualification check.
        * testsuite/23_containers/list/cons/noexcept_move_construct.cc: Likewise.

2021-03-26  Jonathan Wakely  <jwakely@redhat.com>

        * src/c++11/random.cc (USE_LCG): Define when a pseudo-random
        fallback is needed.
        [USE_LCG] (bad_seed, construct_lcg_at, destroy_lcg_at, __lcg):
        New helper functions and callback.
        (random_device::_M_init): Add 'prng' and 'all' enumerators.
        Replace switch with fallthrough with a series of 'if' statements.
        [USE_LCG]: Construct an lcg_type engine and use __lcg when cpuid
        checks fail.
        (random_device::_M_init_pretr1) [USE_MT19937]: Accept "prng"
        token.
        (random_device::_M_getval): Check for callback unconditionally
        and always pass _M_file pointer.
        * testsuite/26_numerics/random/random_device/85494.cc: Remove
        effective-target check. Use new random_device_available helper.
        * testsuite/26_numerics/random/random_device/94087.cc: Likewise.
        * testsuite/26_numerics/random/random_device/cons/default-cow.cc:
        Remove effective-target check.
        * testsuite/26_numerics/random/random_device/cons/default.cc:
        Likewise.
        * testsuite/26_numerics/random/random_device/cons/token.cc: Use
        new random_device_available helper. Test "prng" token.
        * testsuite/util/testsuite_random.h (random_device_available):
        New helper function.

2021-03-25  François Dumont  <fdumont@gcc.gnu.org>

        * include/debug/string
        (basic_string(const basic_string&, const _Alloc&)): Define even if !_GLIBCXX_USE_CXX11_ABI.
        (basic_string(basic_string&&, const _Alloc&)): Likewise and add noexcept qualification.
        (basic_string<>::erase): Adapt to take __const_iterator.
        (basic_string(const _CharT*, const _Allocator&)): Remove assign call.
        (basic_string<>::insert(const_iterator, _InputIte, _InputIte)): Try to
        remove iterator debug layer even if !_GLIBCXX_USE_CXX11_ABI.
        [_GLIBCXX_USE_CHAR8_T] (__gnu_debug::u8string): New.
        (__gnu_debug::u16string, __gnu_debug::u32string): New.
        (std::hash<__gnu_debug::basic_string<>>): New partial specialization.
        (std::__is_fast_hash<__gnu_debug::basic_string<>>): Likewise.
        * testsuite/util/exception/safety.h
        (erase_base<__gnu_debug::basic_string<>>): New partial specialization.
        (insert_base<__gnu_debug::basic_string<>>): Likewise.
        * testsuite/util/testsuite_container_traits.h (traits<__gnu_debug::basic_string<>>):
        New partial specialization.
        * testsuite/21_strings/basic_string/hash/debug.cc: New test.
        * testsuite/21_strings/basic_string/requirements/citerators.cc:
        Add test on __gnu_debug::string.
        * testsuite/21_strings/basic_string/requirements/dr438/constructor.cc: Likewise.
        * testsuite/21_strings/basic_string/requirements/exception/basic.cc: Likewise.
        * testsuite/21_strings/basic_string/requirements/exception/generation_prohibited.cc:
        Likewise.
        * testsuite/21_strings/basic_string/requirements/exception/propagation_consistent.cc:
        Likewise.
        * testsuite/21_strings/basic_string/requirements/explicit_instantiation/char/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string/requirements/explicit_instantiation/char16_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string/requirements/explicit_instantiation/char32_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string/requirements/explicit_instantiation/char8_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string/requirements/explicit_instantiation/wchar_t/1.cc:
        Likewise.
        * testsuite/21_strings/basic_string/requirements/typedefs.cc: Likewise.

2021-03-25  Jakub Jelinek  <jakub@redhat.com>

        PR c++/99672
        * testsuite/18_support/source_location/consteval.cc (main): Adjust
        expected column numbers.
        * testsuite/18_support/source_location/1.cc (main): Likewise.

2021-03-25  Jonathan Wakely  <jwakely@redhat.com>

        * libsupc++/new_opa.cc [!_GLIBCXX_HOSTED]: Declare malloc.

2021-03-25  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/util/exception/safety.h (setup_base::generate):
        Support seeding random engine.
        (erase_point, erase_range): Adjust range of random numbers to
        ensure dereferenceable iterators are used where required.
        (generation_prohibited::run): Do not try to erase from empty
        containers.
        * testsuite/util/testsuite_containergen.h (test_containers):
        Support seeding random engine.

2021-03-23  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/std/ranges/adaptors/reverse.cc: Replace duplicated
        line with a check that uses the const being/end overloads.

2021-03-23  Moritz Sichert  <sichert@in.tum.de>

        * include/std/ranges (reverse_view::begin, reverse_view::end):
        Qualify make_reverse_iterator calls to avoid ADL.
        * testsuite/std/ranges/adaptors/reverse.cc: Test that
        views::reverse works when make_reverse_iterator is defined
        in an associated namespace.

2021-03-23  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/c++config (_GLIBCXX_LONG_DOUBLE_ALT128_COMPAT):
        Do not define when compiling with Clang.

2021-03-22  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/string_view (basic_string_view(Range&&)): Define new
        constructor and deduction guide.
        * testsuite/21_strings/basic_string_view/cons/char/range_c++20.cc: New test.
        * testsuite/21_strings/basic_string_view/cons/wchar_t/range_c++20.cc: New test.

2021-03-22  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/range_access.h (begin(T (&)[N]), end(T (&)[N])):
        Add missing 'noexcept' as per LWG 2280.
        (rbegin(T (&)[N]), rend(T (&)[N]), rbegin(initializer_list<T>))
        (rend(initializer_list<T>)): Add 'noexcept' as per LWG 3537.
        * testsuite/24_iterators/range_access/range_access.cc: Check for
        expected noexcept specifiers. Check result types of generic
        std::begin and std::end overloads.
        * testsuite/24_iterators/range_access/range_access_cpp14.cc:
        Check for expected noexcept specifiers.
        * testsuite/24_iterators/range_access/range_access_cpp17.cc:
        Likewise.

2021-03-19  Jonathan Wakely  <jwakely@redhat.com>

        * 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.

2021-03-16  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99341
        * config/abi/post/aarch64-linux-gnu/baseline_symbols.txt: Remove
        std::once_flag symbols.
        * config/abi/post/ia64-linux-gnu/baseline_symbols.txt: Likewise.
        * config/abi/post/m68k-linux-gnu/baseline_symbols.txt: Likewise.
        * config/abi/post/riscv64-linux-gnu/baseline_symbols.txt:
        Likewise.
        * config/abi/pre/gnu.ver: Likewise.
        * src/c++11/mutex.cc [_GLIBCXX_HAVE_LINUX_FUTEX]
        (struct __once_flag_compat): Remove.
        (_ZNSt9once_flag11_M_activateEv): Remove.
        (_ZNSt9once_flag9_M_finishEb): Remove.

2021-03-16  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99341
        * include/std/mutex [_GLIBCXX_HAVE_LINUX_FUTEX] (once_flag):
        Revert to pthread_once_t implementation.
        [_GLIBCXX_HAVE_LINUX_FUTEX] (call_once): Likewise.
        * src/c++11/mutex.cc [_GLIBCXX_HAVE_LINUX_FUTEX]
        (struct __once_flag_compat): New type matching the reverted
        implementation of once_flag using futexes.
        (once_flag::_M_activate): Remove, replace with ...
        (_ZNSt9once_flag11_M_activateEv): ... alias symbol.
        (once_flag::_M_finish): Remove, replace with ...
        (_ZNSt9once_flag9_M_finishEb): ... alias symbol.
        * testsuite/30_threads/call_once/66146.cc: Removed.

2021-03-15  Iain Sandoe  <iain@sandoe.co.uk>

        * testsuite/17_intro/names.cc: Exclude j from the list
        of test symbols for Darwin.

2021-03-15  Iain Sandoe  <iain@sandoe.co.uk>

        * config/os/bsd/darwin/ppc-extra.ver: Add matching for
        to_chars and from_chars for long double.

2021-03-15  Patrick Palka  <ppalka@redhat.com>

        * include/bits/max_size_type.h (__max_size_type::operator _Tp):
        Fix formatting.
        (__max_size_type::operator++): Define.
        (__max_size_type::operator--): Likewise.
        (__max_size_type::operator<=>): Conditionally define (in place
        of the other comparison operators).
        (__max_diff_type::operator _Tp): Fix formatting.
        (__max_diff_type::operator++): Define.
        (__max_diff_type::operator--): Likewise.
        (__max_diff_type::operator<=>): Conditionally define (in place
        of the other comparison operators).
        * testsuite/std/ranges/iota/max_size_type.cc (test01): Test
        these operator overloads.

2021-03-15  Caroline Tice  <cmtice@google.com>

        PR libstdc++/99172
        * src/Makefile.am (AM_CXXFLAGS_PRE, AM_CXXFLAGS): Add
        AM_CXXFLAGS_PRE with the old definition of AM_CXXFLAGS; make
        AM_CXXFLAGS to be AM_CXXFLAGS_PRE with '-fvtable-verify=std'
        filtered out.
        * src/Makefile.in: Regenerate.

2021-03-11  Patrick Palka  <ppalka@redhat.com>

        * src/c++17/floating_to_chars.cc: Simplify the file as if
        __SIZEOF_INT128__ is always defined.
        [!defined __SIZEOF_INT128__]: Include "uint128_t.h".  Define
        a base-10 to_chars overload for the uint128_t class type.
        * src/c++17/uint128_t.h: New file.
        * testsuite/20_util/to_chars/long_double.cc: No longer expect an
        execution FAIL on targets that have a large long double type
        but lack __int128.

2021-03-11  Patrick Palka  <ppalka@redhat.com>

        * src/c++17/ryu/LOCAL_PATCHES: Update.
        * src/c++17/ryu/d2s_intrinsics.h: Don't define uint128_t.
        * src/c++17/ryu/generic_128.h: Likewise.
        * src/c++17/ryu/ryu_generic_128.h (struct floating_decimal_128):
        Use uint128_t instead of __uint128_t.
        (generic_binary_to_decimal): Likewise.

2021-03-11  Patrick Palka  <ppalka@redhat.com>

        * src/c++17/ryu/LOCAL_PATCHES: New file.

2021-03-11  Patrick Palka  <ppalka@redhat.com>

        * src/c++17/floating_to_chars.cc (uint128_t): New conditionally
        defined alias of unsigned __int128.
        (floating_type_traits_binary128::mantissa_t): Use uint128_t
        instead of unsigned __int128.
        (floating_type_traits<long double>::mantissa_t)
        [LONG_DOUBLE_KIND == LDK_IBM128]: Likewise.
        (get_ieee_repr): Likewise.  Make casts from uint_t to mantissa_t
        and uint32_t explicit.  Simplify the extraction of mantissa,
        exponent and sign bit.

2021-03-11  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/barrier (barrier::arrival_token): New move-only
        class that encapsulates the underlying token value.

2021-03-11  Jonathan Wakely  <jwakely@redhat.com>

        * python/libstdcxx/v6/printers.py (find_type): Use tag attribute
        instead of unqualified() method.

2021-03-11  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99537
        * include/std/stop_token (_Stop_state_t::_M_release_ownership):
        Use acq_rel memory ordering.

2021-03-11  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99533
        * src/c++17/fs_dir.cc (recursive_directory_iterator): Use new
        helper function to check for permission denied errors.
        * src/filesystem/dir.cc (recursive_directory_iterator):
        Likewise.
        * src/filesystem/dir-common.h (is_permission_denied_error): New
        helper function.

2021-03-11  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99536
        * include/bits/random.h (normal_distribution): Use
        default-initializer for _M_saved and _M_saved_available.

2021-03-10  John David Anglin  <danglin@gcc.gnu.org>

        * testsuite/29_atomics/atomic/wait_notify/bool.cc: Add options to
        link with libatomic.
        * testsuite/29_atomics/atomic/wait_notify/generic.cc: Likewise.
        * testsuite/29_atomics/atomic/wait_notify/pointers.cc: Likewise.
        * testsuite/29_atomics/atomic_flag/wait_notify/1.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.
        * testsuite/30_threads/latch/3.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_until.cc: Likewise.

2021-03-10  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99413
        * include/bits/align.h: Include debug/assertions.h.
        * include/bits/codecvt.h: Include bits/c++config.h.
        * include/bits/enable_special_members.h: Likewise.
        * include/bits/erase_if.h: Likewise.
        * include/bits/functional_hash.h: Include <type_traits>.
        * include/bits/invoke.h: Include bits/move.h.
        * include/bits/ostream_insert.h: Include bits/exception_defines.h.
        * include/bits/parse_numbers.h: Include <type_traits>.
        * include/bits/predefined_ops.h: Include bits/c++config.h.
        * include/bits/range_access.h: Include bits/stl_iterator.h.
        * include/bits/stl_bvector.h: Do not include bits/stl_vector.h.
        * include/bits/stl_iterator.h: Include bits/stl_iterator_base_types.h.
        * include/bits/stl_uninitialized.h: Include bits/stl_algobase.h.
        * include/bits/uniform_int_dist.h: Include bits/concept_check.h.
        * include/bits/unique_lock.h: Include bits/std_mutex.h.
        * include/debug/assertions.h: Include bits/c++config.h.

2021-03-10  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/ranges_cmp.h (__eq_builtin_ptr_cmp): Remove.
        (ranges::equal_to, ranges::not_equal_to): Do not constrain
        with __eq_builtin_ptr_cmp.
        (ranges::less, ranges::greater, ranges::less_equal)
        (ranges::greater_equal): Do not constrain with
        __less_builtin_ptr_cmp.
        * libsupc++/compare (compare_three_way): Do not constrain with
        __3way_builtin_ptr_cmp.
        * testsuite/18_support/comparisons/object/builtin-ptr-three-way.cc: Moved to...
        * testsuite/18_support/comparisons/object/lwg3530.cc: ...here.
        * testsuite/20_util/function_objects/range.cmp/lwg3530.cc: New test.

2021-03-10  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/std/time/syn_c++20.cc: Enable synopsis checks for
        C++20 calendar types.

2021-03-06  Jakub Jelinek  <jakub@redhat.com>

        PR libstdc++/99396
        * include/std/bit (__rotl, __rotr): Add optimized variants for power of
        two _Nd which the compiler can pattern match the rotates.

2021-03-04  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99382
        * testsuite/20_util/specialized_algorithms/uninitialized_default_n/sizes.cc:
        Make storage larger than required. Verify no write to the last
        element.
        * testsuite/20_util/specialized_algorithms/uninitialized_value_construct_n/sizes.cc:
        Likewise.

2021-03-03  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>

        * config/abi/post/i386-solaris/baseline_symbols.txt: Regenerate.
        * config/abi/post/i386-solaris/amd64/baseline_symbols.txt:
        Likewise.
        * config/abi/post/sparc-solaris/baseline_symbols.txt: Likewise.
        * config/abi/post/sparc-solaris/sparcv9/baseline_symbols.txt:
        Likewise.

2021-03-03  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>

        * include/experimental/bits/simd.h: Replace reserved _X, _B by
        _Xp, _Bp.
        * include/experimental/bits/simd_builtin.h: Likewise.
        * include/experimental/bits/simd_x86.h: Likewise.

2021-02-27  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99301
        * include/std/chrono (year_month_day::_M_days_since_epoch()):
        Convert chrono::month and chrono::day to unsigned before
        converting to uint32_t.

2021-02-25  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/chrono (year_month_day::_S_from_days): Perform
        all calculations with type uint32_t.

2021-02-25  Jonathan Wakely  <jwakely@redhat.com>

        * doc/xml/manual/abi.xml: Document versioning for GCC 11.
        * doc/html/manual/abi.html: Regenerate.

2021-02-25  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99270
        * testsuite/27_io/headers/cstdio/types_std.cc: Use pointer to
        FILE instead of FILE.

2021-02-25  Andreas Schwab  <schwab@suse.de>

        * config/abi/post/aarch64-linux-gnu/baseline_symbols.txt: Update.
        * config/abi/post/ia64-linux-gnu/baseline_symbols.txt: Update.
        * config/abi/post/m68k-linux-gnu/baseline_symbols.txt: Update.
        * config/abi/post/riscv64-linux-gnu/baseline_symbols.txt: Update.

2021-02-25  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99265
        * include/std/chrono (year_month_day::_S_from_days): Cast long
        to int explicitly.

2021-02-25  Jonathan Wakely  <jwakely@redhat.com>

        * 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.

2021-02-24  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99261
        * src/c++17/floating_to_chars.cc (sprintf_ld): Add extra args
        before value to be printed.

2021-02-24  Patrick Palka  <ppalka@redhat.com>

        * src/c++17/floating_to_chars.cc (__floating_to_chars_precision):
        Relax the condition that guards the printf code path to accept
        F128_type as well as long double.

2021-02-24  Cassio Neri  <cassio.neri@gmail.com>

        * include/std/chrono (year_month_day_last:day): New
        implementation.

2021-02-24  Cassio Neri  <cassio.neri@gmail.com>

        * include/std/chrono (year::is_leap): New implementation.
        * testsuite/std/time/year/2.cc: New test.

2021-02-24  Cassio Neri  <cassio.neri@gmail.com>

        * include/std/chrono (year_month_day::_M_days_since_epoch):
        New implementation.
        * testsuite/std/time/year_month_day/4.cc: New test.

2021-02-24  Cassio Neri  <cassio.neri@gmail.com>

        * include/std/chrono (year_month_day::_S_from_days): New
        implementation.
        * testsuite/std/time/year_month_day/3.cc: New test.

2021-02-24  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/98384
        * testsuite/20_util/to_chars/long_double.cc: Include <optional>.
        (test01): Simplify verifying the nearby values by using a
        2-iteration loop and a dedicated output buffer to check that the
        nearby values are different.  Factor out the printf-based
        verification into a local function, and check that the leading
        hex digits agree before comparing to the output of printf.  Also
        verify the output by round-tripping it through from_chars.

2021-02-24  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/98389
        * config/abi/pre/gnu.ver (GLIBCXX_3.4.29): Do not match to_chars
        symbols for long double arguments mangled as 'g'.
        * config/os/gnu-linux/ldbl-extra.ver: Likewise.
        * config/os/gnu-linux/ldbl-ieee128-extra.ver: Likewise.
        * src/c++17/Makefile.am [GLIBCXX_LDBL_ALT128_COMPAT_TRUE]:
        Use -mabi=ibmlongdouble for floating_to_chars.cc.
        * src/c++17/Makefile.in: Regenerate.
        * src/c++17/floating_to_chars.cc (floating_type_traits_binary128):
        New type defining type traits of IEEE binary128 format.
        (floating_type_traits<__float128>): Define specialization.
        (floating_type_traits<long double>): Define in terms of
        floating_type_traits_binary128 when appropriate.
        (floating_to_shortest_scientific): Handle __float128.
        (sprintf_ld): New function template for printing a long double
        or __ieee128 value using sprintf.
        (__floating_to_chars_shortest, __floating_to_chars_precision):
        Use sprintf_ld.
        (to_chars): Define overloads for __float128.

2021-02-24  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/17_intro/names.cc: Undefine 'u' on powerpc*-linux*.

2021-02-23  Martin Sebor  <msebor@redhat.com>

        PR c++/99074
        * libsupc++/dyncast.cc (__dynamic_cast): Return null when
        first argument is null.

2021-02-23  Jakub Jelinek  <jakub@redhat.com>

        PR libstdc++/99181
        * testsuite/21_strings/char_traits/requirements/char/99181.cc: New
        test.

2021-02-23  Jakub Jelinek  <jakub@redhat.com>

        PR libstdc++/99181
        * include/bits/char_traits.h (char_traits<char>::compare): For
        constexpr evaluation don't call
        __gnu_cxx::char_traits<char_type>::compare but do the comparison loop
        directly.

2021-02-23  Jakub Jelinek  <jakub@redhat.com>

        PR libstdc++/97549
        * include/pstl/parallel_backend_serial.h: Remove __pstl::__par_backend.

2021-02-23  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/98384
        * src/c++17/floating_to_chars.cc (get_ieee_repr): Extract
        the high- and low-order parts from an IBM long double value
        in an endian-agnostic way.

2021-02-19  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/atomic_wait.h (__thread_relax()): Call
        __thread_yield() not __gthread_yield().

2021-02-15  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/atomic_wait.h (__thread_yield()): Check
        _GLIBCXX_HAS_GTHREADS before using __gthread_yield.
        (__thread_relax()): Use __thread_yield() instead of repeating
        the preprocessor checks for __gthread_yield.

2021-02-15  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/mutex (once_flag::_M_activate()): Add explicit
        return statement for passive case.
        (once_flag::_M_finish(bool)): Use reserved name for parameter.

2021-02-14  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99096
        * testsuite/util/testsuite_fs.h: Always include <unistd.h>.

2021-02-12  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/88881
        * src/c++17/fs_ops.cc (fs::symlink_status): Re-enable workaround.

2021-02-12  Jonathan Wakely  <jwakely@redhat.com>

        * doc/xml/manual/status_cxx2014.xml: Document implementation
        specific properties of std::experimental::filesystem::rename.
        * doc/xml/manual/status_cxx2017.xml: Document implementation
        specific properties of std::filesystem::rename.
        * doc/html/*: Regenerate.
        * src/c++17/fs_ops.cc (fs::rename): Implement correct behaviour
        for directories on Windows.
        * src/filesystem/ops-common.h (__gnu_posix::rename): Use
        MoveFileExW on Windows.
        * testsuite/27_io/filesystem/operations/rename.cc: New test.
        * testsuite/experimental/filesystem/operations/rename.cc: New test.

2021-02-12  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/util/testsuite_fs.h (nonexistent_path): Add
        random number to the path.

2021-02-12  Jonathan Wakely  <jwakely@redhat.com>

        * include/experimental/internet (address_v6::to_string): Include
        scope ID in string.
        * testsuite/experimental/net/internet/address/v6/members.cc:
        Test to_string() results.

2021-02-12  Jonathan Wakely  <jwakely@redhat.com>

        * include/experimental/internet (address_v6::any): Avoid using
        memcpy in constexpr function.
        (address_v6::loopback): Likewise.
        (make_address_v6): Fix missing return statements on error paths.
        * include/experimental/io_context: Avoid -Wdangling-else
        warning.
        * testsuite/experimental/net/internet/address/v4/members.cc:
        Remove unused variables.
        * testsuite/experimental/net/internet/address/v6/members.cc:
        New test.

2021-02-12  Jonathan Wakely  <jwakely@redhat.com>

        * include/bits/shared_ptr_base.h (__shared_ptr::_M_get_deleter):
        Add unused attribute to parameter.
        * src/c++11/shared_ptr.cc (_Sp_make_shared_tag::_S_eq):
        Likewise.

2021-02-12  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/27_io/basic_ostream/emit/1.cc: Expect test to fail
        if -fno-rtti is used.
        * testsuite/30_threads/async/forced_unwind.cc: Expect test
        to abort if -fno-rtti is used.

2021-02-12  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/util/testsuite_allocator.h (memory_resource):
        Remove requirement for RTTI and exceptions to be enabled.

2021-02-12  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/27_io/basic_istringstream/rdbuf/char/2832.cc: Use
        static_cast when RTTI is disabled.
        * testsuite/27_io/basic_istringstream/rdbuf/wchar_t/2832.cc:
        Likewise.
        * testsuite/27_io/basic_ostringstream/rdbuf/char/2832.cc:
        Likewise.
        * testsuite/27_io/basic_ostringstream/rdbuf/wchar_t/2832.cc:
        Likewise.
        * testsuite/27_io/basic_stringstream/str/char/2.cc:
        Likewise.
        * testsuite/27_io/basic_stringstream/str/wchar_t/2.cc:
        Likewise.

2021-02-12  Jonathan Wakely  <jwakely@redhat.com>

        * include/std/ostream (__syncbuf_base::_S_get): Mark parameter
        as unused and only use dynamic_cast when RTTI is enabled.

2021-02-12  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99077
        * src/c++11/cxx11-ios_failure.cc (__ios_failure(const char*, int)):
        Change int parameter to error_code, to match std::ios_failure.
        (__throw_ios_failure(const char*, int)): Construct error_code
        from int parameter.

2021-02-11  Jonathan Wakely  <jwakely@redhat.com>

        * libsupc++/eh_ptr.cc (_GLIBCXX_EH_PTR_RELOPS_COMPAT): Define
        new macro.
        * libsupc++/exception_ptr.h (_GLIBCXX_EH_PTR_USED): Check new
        macro instead of _GLIBCXX_EH_PTR_COMPAT.
        (operator==): Likewise.

2021-02-11  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99058
        * doc/xml/manual/status_cxx2011.xml: Document when support
        became stable.
        * doc/xml/manual/status_cxx2014.xml: Likewise.
        * doc/xml/manual/status_cxx2017.xml: Likewise.
        * doc/html/manual/status.html: Regenerate.

2021-02-10  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/88881
        * src/c++17/fs_ops.cc (fs::status): Re-enable workaround.

2021-02-10  Jonathan Wakely  <jwakely@redhat.com>

        * src/c++17/fs_ops.cc (fs::create_hard_link, fs::equivalent)
        (fs::remove): Use std::system_category() for error codes from
        GetLastError().
        * src/filesystem/ops.cc (fs::create_hard_link, fs::remove):
        Likewise.

2021-02-10  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/27_io/filesystem/operations/proximate.cc: Fix typo
        in __MINGW32__ macro name.
        * testsuite/27_io/filesystem/path/compare/lwg2936.cc: Likewise.
        * testsuite/27_io/filesystem/path/generation/proximate.cc:
        Likewise.
        * testsuite/27_io/filesystem/path/generation/relative.cc:
        Likewise.
        * testsuite/util/testsuite_fs.h: Likewise.

2021-02-09  François Dumont  <fdumont@gcc.gnu.org>

        * include/bits/stl_tree.h
        (__has_is_transparent, __has_is_transparent_t): Move...
        * include/bits/stl_function.h: ...here.
        * include/bits/hashtable_policy.h (_Hash_code_base<>::_M_hash_code_tr): New..
        (_Hashtable_base<>::_M_equals_tr): New.
        * include/bits/hashtable.h (_Hashtable<>::_M_find_tr, _Hashtable<>::_M_count_tr,
        _Hashtable<>::_M_equal_range_tr): New member function templates to perform
        heterogeneous lookup.
        (_Hashtable<>::_M_find_before_node_tr): New.
        (_Hashtable<>::_M_find_node_tr): New.
        * include/bits/unordered_map.h (unordered_map::find<>, unordered_map::count<>,
        unordered_map::contains<>, unordered_map::equal_range<>): New member function
        templates to perform heterogeneous lookup.
        (unordered_multimap::find<>, unordered_multimap::count<>,
        unordered_multimap::contains<>, unordered_multimap::equal_range<>): Likewise.
        * include/bits/unordered_set.h  (unordered_set::find<>, unordered_set::count<>,
        unordered_set::contains<>, unordered_set::equal_range<>): Likewise.
        (unordered_multiset::find<>, unordered_multiset::count<>,
        unordered_multiset::contains<>, unordered_multiset::equal_range<>): Likewise.
        * include/debug/unordered_map
        (unordered_map::find<>, unordered_map::equal_range<>): Likewise.
        (unordered_multimap::find<>, unordered_multimap::equal_range<>): Likewise.
        * include/debug/unordered_set
        (unordered_set::find<>, unordered_set::equal_range<>): Likewise.
        (unordered_multiset::find<>, unordered_multiset::equal_range<>): Likewise.
        * testsuite/23_containers/unordered_map/operations/1.cc: New test.
        * testsuite/23_containers/unordered_multimap/operations/1.cc: New test.
        * testsuite/23_containers/unordered_multiset/operations/1.cc: New test.
        * testsuite/23_containers/unordered_set/operations/1.cc: New test.

2021-02-09  François Dumont  <fdumont@gcc.gnu.org>

        * include/bits/stl_deque.h
        (std::operator-(deque::iterator, deque::iterator)): Replace if/then with
        a null pointer test.

2021-02-09  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/27_io/filesystem/operations/remove_all.cc: Remove
        test directory after making it writable again.
        * testsuite/experimental/filesystem/operations/remove_all.cc:
        Likewise.

2021-02-09  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/99021
        * include/std/coroutine (coroutine_handle<P>::from_address): Add
        noexcept.

2021-02-09  Vladimir Vishnevsky  <vv.os.swe@gmail.com>

        * include/ext/stdio_sync_filebuf.h: Remove unused <unistd.h>.
        * src/c++17/fs_ops.cc (fs::permissions): Qualify mode_t.

2021-02-09  Jakub Jelinek  <jakub@redhat.com>

        PR middle-end/98465
        * include/bits/basic_string.tcc (basic_string::_M_replace): When __s
        points to the characters moved by earlier _S_move, compute the source
        address using expression based on the __p pointer rather than __s
        pointer.

2021-02-03  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/19_diagnostics/error_code/operators/not_equal.cc:
        Add comparison with same category and different values.
        * testsuite/19_diagnostics/error_code/operators/less.cc:
        Likewise. Fix comparison involving different categories.
        * testsuite/19_diagnostics/error_code/operators/three_way.cc:
        Likewise.
        * testsuite/19_diagnostics/error_condition/operators/less.cc:
        Add comment.
        * testsuite/19_diagnostics/error_condition/operators/three_way.cc:
        Likewise.

2021-02-03  yaozhongxiao  <yaozhongxiao@linux.alibaba.com>

        * include/experimental/bits/simd_neon.h: Replace repeated vpadd
        calls with a single vaddv for aarch64.

2021-02-03  Matthias Kretz  <kretz@kde.org>

        * testsuite/Makefile.am: Warn about the workaround. Add
        -fno-tree-vrp to CXXFLAGS passed to the check_simd script.
        Improve initial user feedback from make check-simd.
        * testsuite/Makefile.in: Regenerated.

2021-02-03  Matthias Kretz  <kretz@kde.org>

        * include/experimental/bits/simd.h: Add __detail::_Minimum and
        __detail::_Maximum to use them as _BinaryOperation to _S_reduce.
        Add hmin and hmax overloads for simd and const_where_expression.
        * include/experimental/bits/simd_scalar.h
        (_SimdImplScalar::_S_reduce): Make unused _BinaryOperation
        parameter const-ref to allow calling _S_reduce with an rvalue.
        * testsuite/experimental/simd/tests/reductions.cc: Add tests for
        hmin and hmax. Since the compiler statically determined that all
        tests pass, repeat the test after a call to make_value_unknown.

2021-02-03  Matthias Kretz  <kretz@kde.org>

        * testsuite/experimental/simd/tests/bits/verify.h (verify): Add
        instruction pointer data member. Ensure that the `if (m_failed)`
        branch is always inlined into the calling code. The body of the
        conditional can still be a function call. Move the get_ip call
        into the verify ctor to simplify the ctor calls.
        (COMPARE): Don't mention the use of all_of for reduction of a
        simd_mask. It only distracts from the real issue.

2021-02-03  Matthias Kretz  <kretz@kde.org>

        * testsuite/experimental/simd/driver.sh: Abstract reading test
        options into read_src_option function. Read skip, only,
        expensive, and xfail via read_src_option. Add timeout and
        timeout-factor options and adjust timeout variable accordingly.
        * testsuite/experimental/simd/tests/loadstore.cc: Set
        timeout-factor 2.

2021-02-03  Matthias Kretz  <kretz@kde.org>

        * testsuite/experimental/simd/driver.sh: When handling the pipe
        to log (and on verbose to stdout) count the lines. If it exceeds
        1000 log the issue and exit 125, which is then handled as a
        failure.

2021-02-03  Matthias Kretz  <kretz@kde.org>

        * testsuite/experimental/simd/tests/hypot3_fma.cc: Add skip:
        markup for long double on powerpc64*.

2021-02-03  Matthias Kretz  <kretz@kde.org>

        * include/experimental/bits/simd.h: Add __have_power10vec
        conditional on _ARCH_PWR10.
        * include/experimental/bits/simd_builtin.h: Forward declare
        _MaskImplPpc and use it as _MaskImpl when __ALTIVEC__ is
        defined.
        (_MaskImplBuiltin::_S_some_of): Call _S_popcount from the
        _SuperImpl for optimizations and correctness.
        * include/experimental/bits/simd_ppc.h: Add _MaskImplPpc.
        (_MaskImplPpc::_S_popcount): Implement via vec_cntm for POWER10.
        Otherwise, for >=int use -vec_sums divided by a sizeof factor.
        For <int use -vec_sums(vec_sum4s(...)) to sum all mask entries.

2021-02-03  Matthias Kretz  <kretz@kde.org>

        * testsuite/experimental/simd/driver.sh: Remove executable on
        SIGINT. Process compiler and test executable output: In verbose
        mode print messages immediately, limited to 1000 lines and
        breaking long lines to below $COLUMNS (or 1024 if not set).
        Communicating the exit status of the compiler / test with the
        necessary pipe is done via a message through stdout/-in.

2021-02-03  Matthias Kretz  <kretz@kde.org>

        * testsuite/Makefile.am: Ensure .simd.summary is empty before
        collecting a new summary.
        * testsuite/Makefile.in: Regenerate.

2021-02-03  Matthias Kretz  <kretz@kde.org>

        * testsuite/experimental/simd/generate_makefile.sh: Use
        different variables internally than documented for user
        overrides. This makes internal append/prepend work as intended.

2021-02-03  Matthias Kretz  <kretz@kde.org>

        * testsuite/experimental/simd/driver.sh (verify_test): Print
        test output on run xfail. Do not repeat lines from the log that
        were already printed on stdout.
        (test_selector): Make the compiler flags pattern usable as a
        substring selector.
        (toplevel): Trap on SIGINT and remove the log and sum files.
        Call timout with --foreground to quickly terminate on SIGINT.
        * testsuite/experimental/simd/generate_makefile.sh: Simplify run
        targets via target patterns. Default DRIVEROPTS to -v for run
        targets. Remove log and sum files after completion of the run
        target (so that it's always recompiled).
        Place help text into text file for reasonable 'make help'
        performance.

2021-02-03  Matthias Kretz  <kretz@kde.org>

        * include/experimental/bits/simd.h: Remove unnecessary static
        assertion. Allow sizeof(8) integer __intrinsic_type to enable
        the necessary mask type.

2021-02-03  Matthias Kretz  <kretz@kde.org>

        * include/experimental/bits/simd.h: Let __intrinsic_type<long
        double, N> be valid if sizeof(long double) == sizeof(double) and
        use a __vector double as member type.

2021-02-03  Matthias Kretz  <kretz@kde.org>

        * include/experimental/bits/simd.h (__is_intrinsic_type): New
        internal type trait. Alias for __is_vector_type on x86.
        (_VectorTraitsImpl): Enable for __intrinsic_type in addition for
        __vector_type.
        (__intrin_bitcast): Allow casting to & from vector & intrinsic
        types.
        (__intrinsic_type): Explicitly specialize for NEON intrinsic
        vector types.

2021-02-03  Matthias Kretz  <kretz@kde.org>

        * testsuite/experimental/simd/driver.sh: Implement skip, only,
        expensive, and xfail markers. They can select on type, ABI tag
        subset number, target-triplet, and compiler flags.
        * testsuite/experimental/simd/generate_makefile.sh: The summary
        now includes lines for unexpected passes and expected failures.
        If the skip or only markers are only conditional on the type, do
        not generate rules for those types.
        * testsuite/experimental/simd/tests/abs.cc: Mark test expensive
        for ABI tag subsets 1-9.
        * testsuite/experimental/simd/tests/algorithms.cc: Ditto.
        * testsuite/experimental/simd/tests/broadcast.cc: Ditto.
        * testsuite/experimental/simd/tests/casts.cc: Ditto.
        * testsuite/experimental/simd/tests/generator.cc: Ditto.
        * testsuite/experimental/simd/tests/integer_operators.cc: Ditto.
        * testsuite/experimental/simd/tests/loadstore.cc: Ditto.
        * testsuite/experimental/simd/tests/mask_broadcast.cc: Ditto.
        * testsuite/experimental/simd/tests/mask_conversions.cc: Ditto.
        * testsuite/experimental/simd/tests/mask_implicit_cvt.cc: Ditto.
        * testsuite/experimental/simd/tests/mask_loadstore.cc: Ditto.
        * testsuite/experimental/simd/tests/mask_operator_cvt.cc: Ditto.
        * testsuite/experimental/simd/tests/mask_operators.cc: Ditto.
        * testsuite/experimental/simd/tests/mask_reductions.cc: Ditto.
        * testsuite/experimental/simd/tests/operator_cvt.cc: Ditto.
        * testsuite/experimental/simd/tests/operators.cc: Ditto.
        * testsuite/experimental/simd/tests/reductions.cc: Ditto.
        * testsuite/experimental/simd/tests/simd.cc: Ditto.
        * testsuite/experimental/simd/tests/split_concat.cc: Ditto.
        * testsuite/experimental/simd/tests/splits.cc: Ditto.
        * testsuite/experimental/simd/tests/where.cc: Ditto.
        * testsuite/experimental/simd/tests/fpclassify.cc: Ditto. In
        addition replace "test only floattypes" marker by unconditional
        "float|double|ldouble" only marker.
        * testsuite/experimental/simd/tests/frexp.cc: Ditto.
        * testsuite/experimental/simd/tests/hypot3_fma.cc: Ditto.
        * testsuite/experimental/simd/tests/ldexp_scalbn_scalbln_modf.cc:
        Ditto.
        * testsuite/experimental/simd/tests/logarithm.cc: Ditto.
        * testsuite/experimental/simd/tests/math_1arg.cc: Ditto.
        * testsuite/experimental/simd/tests/math_2arg.cc: Ditto.
        * testsuite/experimental/simd/tests/remqo.cc: Ditto.
        * testsuite/experimental/simd/tests/trigonometric.cc: Ditto.
        * testsuite/experimental/simd/tests/trunc_ceil_floor.cc: Ditto.
        * testsuite/experimental/simd/tests/sincos.cc: Ditto. In
        addition, xfail on run because the reference data is missing.

2021-02-02  Jonathan Wakely  <jwakely@redhat.com>

        * doc/xml/manual/status_cxx2011.xml: Remove stray table cell.
        * doc/xml/manual/status_cxx2014.xml: Likewise.
        * doc/xml/manual/status_cxx2017.xml: Likewise.
        * doc/html/manual/status.html: Regenerate.

2021-02-01  François Dumont  <fdumont@gcc.gnu.org>

        PR libstdc++/70303
        * include/bits/stl_deque.h (std::deque<>::operator-(iterator, iterator)):
        Return 0 if both iterators are value-initialized.
        * testsuite/23_containers/deque/70303.cc: New test.
        * testsuite/23_containers/vector/70303.cc: New test.

2021-02-01  Jonathan Wakely  <jwakely@redhat.com>

        * doc/xml/manual/status_cxx2011.xml: Update std::call_once
        status.
        * doc/xml/manual/status_cxx2014.xml: Likewise.
        * doc/xml/manual/status_cxx2017.xml: Likewise. Update
        std::from_chars and std::to_chars status. Fix formatting.
        * doc/html/manual/status.html: Regenerate.

2021-01-28  Jonathan Wakely  <jwakely@redhat.com>

        * include/experimental/bits/numeric_traits.h: Update copyright
        dates.
        * include/experimental/bits/simd.h: Likewise.
        * include/experimental/bits/simd_builtin.h: Likewise.
        * include/experimental/bits/simd_converter.h: Likewise.
        * include/experimental/bits/simd_detail.h: Likewise.
        * include/experimental/bits/simd_fixed_size.h: Likewise.
        * include/experimental/bits/simd_math.h: Likewise.
        * include/experimental/bits/simd_neon.h: Likewise.
        * include/experimental/bits/simd_ppc.h: Likewise.
        * include/experimental/bits/simd_scalar.h: Likewise.
        * include/experimental/bits/simd_x86.h: Likewise.
        * include/experimental/bits/simd_x86_conversions.h: Likewise.
        * include/experimental/simd: Likewise.
        * testsuite/experimental/simd/*: Likewise.

2021-01-27  Jonathan Wakely  <jwakely@redhat.com>

        * doc/xml/manual/status_cxx2017.xml: Replace invalid entity.
        * doc/html/*: Regenerate.

2021-01-27  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/experimental/simd/generate_makefile.sh: Use printf
        instead of echo when printing escape characters.

2021-01-27  Matthias Kretz  <kretz@kde.org>

        * scripts/check_simd: New file. This script is called from the
        the check-simd target. It determines a set of compiler flags and
        simulator setups for calling generate_makefile.sh and passes the
        information back to the check-simd target, which recurses to the
        generated Makefiles.
        * scripts/create_testsuite_files: Remove files below simd/tests/
        from testsuite_files and place them in testsuite_files_simd.
        * testsuite/Makefile.am: Add testsuite_files_simd. Add
        check-simd target.
        * testsuite/Makefile.in: Regenerate.
        * testsuite/experimental/simd/driver.sh: New file. This script
        compiles and runs a given simd test, logging its output and
        status. It uses the timeout command to implement compile and
        test timeouts.
        * testsuite/experimental/simd/generate_makefile.sh: New file.
        This script generates a Makefile which uses driver.sh to compile
        and run the tests and collect the logs into a single log file.
        * testsuite/experimental/simd/tests/abs.cc: New file. Tests
        abs(simd).
        * testsuite/experimental/simd/tests/algorithms.cc: New file.
        Tests min/max(simd, simd).
        * testsuite/experimental/simd/tests/bits/conversions.h: New
        file. Contains functions to support tests involving conversions.
        * testsuite/experimental/simd/tests/bits/make_vec.h: New file.
        Support functions make_mask and make_vec.
        * testsuite/experimental/simd/tests/bits/mathreference.h: New
        file. Support functions to supply precomputed math function
        reference data.
        * testsuite/experimental/simd/tests/bits/metahelpers.h: New
        file. Support code for SFINAE testing.
        * testsuite/experimental/simd/tests/bits/simd_view.h: New file.
        * testsuite/experimental/simd/tests/bits/test_values.h: New
        file. Test functions to easily drive a test with simd objects
        initialized from a given list of values and a range of random
        values.
        * testsuite/experimental/simd/tests/bits/ulp.h: New file.
        Support code to determine the ULP distance of simd objects.
        * testsuite/experimental/simd/tests/bits/verify.h: New file.
        Test framework for COMPARE'ing simd objects and instantiating
        the test templates with value_type and ABI tag.
        * testsuite/experimental/simd/tests/broadcast.cc: New file. Test
        simd broadcasts.
        * testsuite/experimental/simd/tests/casts.cc: New file. Test
        simd casts.
        * testsuite/experimental/simd/tests/fpclassify.cc: New file.
        Test floating-point classification functions.
        * testsuite/experimental/simd/tests/frexp.cc: New file. Test
        frexp(simd).
        * testsuite/experimental/simd/tests/generator.cc: New file. Test
        simd generator constructor.
        * testsuite/experimental/simd/tests/hypot3_fma.cc: New file.
        Test 3-arg hypot(simd,simd,simd) and fma(simd,simd,sim).
        * testsuite/experimental/simd/tests/integer_operators.cc: New
        file. Test integer operators.
        * testsuite/experimental/simd/tests/ldexp_scalbn_scalbln_modf.cc:
        New file. Test ldexp(simd), scalbn(simd), scalbln(simd), and
        modf(simd).
        * testsuite/experimental/simd/tests/loadstore.cc: New file. Test
        (converting) simd loads and stores.
        * testsuite/experimental/simd/tests/logarithm.cc: New file. Test
        log*(simd).
        * testsuite/experimental/simd/tests/mask_broadcast.cc: New file.
        Test simd_mask broadcasts.
        * testsuite/experimental/simd/tests/mask_conversions.cc: New
        file. Test simd_mask conversions.
        * testsuite/experimental/simd/tests/mask_implicit_cvt.cc: New
        file. Test simd_mask implicit conversions.
        * testsuite/experimental/simd/tests/mask_loadstore.cc: New file.
        Test simd_mask loads and stores.
        * testsuite/experimental/simd/tests/mask_operator_cvt.cc: New
        file. Test simd_mask operators convert as specified.
        * testsuite/experimental/simd/tests/mask_operators.cc: New file.
        Test simd_mask compares, subscripts, and negation.
        * testsuite/experimental/simd/tests/mask_reductions.cc: New
        file. Test simd_mask reductions.
        * testsuite/experimental/simd/tests/math_1arg.cc: New file. Test
        1-arg math functions on simd.
        * testsuite/experimental/simd/tests/math_2arg.cc: New file. Test
        2-arg math functions on simd.
        * testsuite/experimental/simd/tests/operator_cvt.cc: New file.
        Test implicit conversions on simd binary operators behave as
        specified.
        * testsuite/experimental/simd/tests/operators.cc: New file. Test
        simd compares, subscripts, not, unary minus, plus, minus,
        multiplies, divides, increment, and decrement.
        * testsuite/experimental/simd/tests/reductions.cc: New file.
        Test reduce(simd).
        * testsuite/experimental/simd/tests/remqo.cc: New file. Test
        remqo(simd).
        * testsuite/experimental/simd/tests/simd.cc: New file. Basic
        sanity checks of simd types.
        * testsuite/experimental/simd/tests/sincos.cc: New file. Test
        sin(simd) and cos(simd).
        * testsuite/experimental/simd/tests/split_concat.cc: New file.
        Test split(simd) and concat(simd, simd).
        * testsuite/experimental/simd/tests/splits.cc: New file. Test
        split(simd_mask).
        * testsuite/experimental/simd/tests/trigonometric.cc: New file.
        Test remaining trigonometric functions on simd.
        * testsuite/experimental/simd/tests/trunc_ceil_floor.cc: New
        file. Test trunc(simd), ceil(simd), and floor(simd).
        * testsuite/experimental/simd/tests/where.cc: New file. Test
        masked operations using where.

2021-01-27  Matthias Kretz  <kretz@kde.org>

        * doc/xml/manual/status_cxx2017.xml: Add implementation status
        of the Parallelism TS 2. Document implementation-defined types
        and behavior.
        * include/Makefile.am: Add new headers.
        * include/Makefile.in: Regenerate.
        * include/experimental/simd: New file. New header for
        Parallelism TS 2.
        * include/experimental/bits/numeric_traits.h: New file.
        Implementation of P1841R1 using internal naming. Addition of
        missing IEC559 functionality query.
        * include/experimental/bits/simd.h: New file. Definition of the
        public simd interfaces and general implementation helpers.
        * include/experimental/bits/simd_builtin.h: New file.
        Implementation of the _VecBuiltin simd_abi.
        * include/experimental/bits/simd_converter.h: New file. Generic
        simd conversions.
        * include/experimental/bits/simd_detail.h: New file. Internal
        macros for the simd implementation.
        * include/experimental/bits/simd_fixed_size.h: New file. Simd
        fixed_size ABI specific implementations.
        * include/experimental/bits/simd_math.h: New file. Math
        overloads for simd.
        * include/experimental/bits/simd_neon.h: New file. Simd NEON
        specific implementations.
        * include/experimental/bits/simd_ppc.h: New file. Implement bit
        shifts to avoid invalid results for integral types smaller than
        int.
        * include/experimental/bits/simd_scalar.h: New file. Simd scalar
        ABI specific implementations.
        * include/experimental/bits/simd_x86.h: New file. Simd x86
        specific implementations.
        * include/experimental/bits/simd_x86_conversions.h: New file.
        x86 specific conversion optimizations. The conversion patterns
        work around missing conversion patterns in the compiler and
        should be removed as soon as PR85048 is resolved.
        * testsuite/experimental/simd/standard_abi_usable.cc: New file.
        Test that all (not all fixed_size<N>, though) standard simd and
        simd_mask types are usable.
        * testsuite/experimental/simd/standard_abi_usable_2.cc: New
        file. As above but with -ffast-math.
        * testsuite/libstdc++-dg/conformance.exp: Don't build simd tests
        from the standard test loop. Instead use
        check_vect_support_and_set_flags to build simd tests with the
        relevant machine flags.

2021-01-27  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/66414
        * include/bits/string_view.tcc
        (basic_string_view::find(const CharT*, size_type, size_type)):
        Optimize.

2021-01-27  Paul Fee  <paul.f.fee@gmail.com>

        * 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.

2021-01-21  Jonathan Wakely  <jwakely@redhat.com>

        * src/c++17/Makefile.in: Regenerate.

2021-01-20  David Edelsohn  <dje.gcc@gmail.com>

        * config/os/aix/ctype_inline.h (bool ctype<char>:: is): Cast
        _OBJ_DATA subscript to unsigned char. Add _THREAD_SAFE access to
        __lc_type.
        (const char* ctype<char>:: is): Same.

2021-01-18  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/98725
        * testsuite/20_util/unique_ptr/io/lwg2948.cc:  Do not try to
        write to a wide character stream if wide character support is
        disabled in the library.

2021-01-18  Jonathan Wakely  <jwakely@redhat.com>

        * testsuite/27_io/basic_stringstream/cons/char/1.cc: Use
        stringbuf not wstringbuf.

2021-01-18  Jakub Jelinek  <jakub@redhat.com>

        PR debug/98708
        * src/c++11/Makefile.am (cxx11-ios_failure-lt.s, cxx11-ios_failure.s):
        Compile with -gno-as-loc-support.
        * src/c++11/Makefile.in: Regenerated.

2021-01-16  H.J. Lu  <hjl.tools@gmail.com>

        * testsuite/29_atomics/atomic_flag/test_and_set/explicit-hle.cc:
        Add -fcf-protection=none to -march=i486.

2021-01-14  François Dumont  <fdumont@gcc.gnu.org>

        * testsuite/23_containers/deque/debug/98466.cc: Make it pre-C++11
        compliant.

2021-01-14  Alexandre Oliva  <oliva@adacore.com>

        * testsuite/30_threads/future/members/poll.cc: Calibrate
        iteration count.

2021-01-14  François Dumont  <fdumont@gcc.gnu.org>

        PR libstdc++/98466
        * include/bits/hashtable_policy.h (_Node_iterator_base()): Set _M_cur to nullptr.
        (_Node_iterator()): Make default.
        (_Node_const_iterator()): Make default.
        * include/debug/macros.h (__glibcxx_check_erae_range_after): Add _M_singular
        iterator checks.
        * include/debug/safe_iterator.h
        (_GLIBCXX_DEBUG_VERIFY_OPERANDS): Accept if both iterator are value initialized.
        * include/debug/safe_local_iterator.h (_GLIBCXX_DEBUG_VERIFY_OPERANDS):
        Likewise.
        * include/debug/safe_iterator.tcc (_Safe_iterator<>::_M_valid_range): Add
        _M_singular checks on input iterators.
        * src/c++11/debug.cc (_Safe_iterator_base::_M_can_compare): Remove _M_singular
        checks.
        * testsuite/23_containers/deque/debug/98466.cc: New test.
        * testsuite/23_containers/unordered_map/debug/98466.cc: New test.

2021-01-14  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/98471
        * include/bits/fs_path.h (__throw_conversion_error): New
        function to throw or abort on character conversion errors.
        (__wstr_from_utf8): Move definition after filesystem_error has
        been defined. Use __throw_conversion_error.
        (path::_S_convert<_EcharT>): Use __throw_conversion_error.
        (path::_S_str_convert<_CharT, _Traits, _Allocator>): Likewise.
        (path::u8string): Likewise.

2021-01-14  Jonathan Wakely  <jwakely@redhat.com>

        * 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.

2021-01-13  Jonathan Wakely  <jwakely@redhat.com>

        * doc/doxygen/user.cfg.in (INPUT): Remove include/debug/array.

2021-01-10  David Edelsohn  <dje.gcc@gmail.com>

        PR libstdc++/98613
        * testsuite/ext/vstring/cons/moveable.cc: Suppress false positive
        warning.
        * testsuite/ext/vstring/modifiers/assign/move_assign.cc: Same.

2021-01-08  Olivier Hainque  <hainque@adacore.com>

        * testsuite/20_util/bind/ref_neg.cc: Tweak the
        dg-prune-output regex for out-of-build-tree contexts.

2021-01-07  Thomas Rodgers  <trodgers@redhat.com>

        * 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  Patrick Palka  <ppalka@redhat.com>

        PR libstdc++/98384
        * testsuite/20_util/to_chars/long_double.cc: Use nexttowardl
        instead of the non-standard nextupl and nextdownl.

2021-01-05  Samuel Thibault  <samuel.thibault@ens-lyon.org>

        * configure: Re-generate.

2021-01-05  Ed Smith-Rowland  <3dw4rd@verizon.net>

        * include/precompiled/stdc++.h: Add <source_location> to C++20 section.

2021-01-01  Jakub Jelinek  <jakub@redhat.com>

        * ChangeLog-2020: Rotate ChangeLog.  New file.

\f
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