This changes how arrays of unknown bound and/or incomplete element type
are handled.

	* include/bits/range_access.h (ranges::begin): Reject array of
	incomplete type.
	(ranges::end, ranges::size): Require arrays to be bounded.
	(ranges::data): Require lvalue or borrowed_range.
	(ranges::iterator_t): Remove constraint.
	* testsuite/std/ranges/access/begin.cc: Do not check array of
	incomplete type.
	* testsuite/std/ranges/access/begin_neg.cc: New test.
	* testsuite/std/ranges/access/end_neg.cc: Adjust expected error.
	* testsuite/std/ranges/access/size_neg.cc: Adjust expected error.
	* testsuite/std/ranges/access/ssize.cc: Do not check array of
	incomplete type.

Another piece of P1614R2 for C++20.

This also adds tests for operator< in C++11, which was present but
untested.

	* include/std/system_error (error_category::operator<=>)
	(operator<=>(const error_code&, const error_code&))
	(operator<=>(const error_condition&, const error_condition&)): Define
	for C++20.
	* testsuite/19_diagnostics/error_category/operators/less.cc: New test.
	* testsuite/19_diagnostics/error_category/operators/three_way.cc: New
	test.
	* testsuite/19_diagnostics/error_code/operators/equal.cc: Remove
	incorrect comment.
	* testsuite/19_diagnostics/error_code/operators/less.cc: New test.
	* testsuite/19_diagnostics/error_code/operators/not_equal.cc: Remove
	incorrect comment.
	* testsuite/19_diagnostics/error_code/operators/three_way.cc: New test.
	* testsuite/19_diagnostics/error_condition/operators/equal.cc: Remove
	incorrect comment.
	* testsuite/19_diagnostics/error_condition/operators/less.cc: New test.
	* testsuite/19_diagnostics/error_condition/operators/not_equal.cc:
	Remove incorrect comment.
	* testsuite/19_diagnostics/error_condition/operators/three_way.cc: New
	test.

This function can be synthesized by the compiler now.

	* libsupc++/typeinfo (type_info::operator!=): Remove for C++20.

	* include/std/thread (thread::id::operator<=>): Define for C++20.
	* testsuite/30_threads/thread/id/70294.cc: Do not take addresses of
	functions in namespace std.
	* testsuite/30_threads/thread/id/operators_c++20.cc: New test.

	PR translation/93841
	* config/or1k/or1k.opt: Remove superfluous word.
	* doc/invoke.texi: Likewise.

	PR translation/93838
	* parser.c (cp_parser_decl_specifier_seq): Remove trailing space.

	PR translation/93831
	* config/darwin.c (darwin_override_options): Change 64b to 64-bit mode.

	PR translation/93830
	* common/config/avr/avr-common.c: Remote trailing "|".

	* de.po: Update.

In order to detect modifying constant objects in constexpr evaluation,
which is UB, in r10-2655 I added code that sets TREE_READONLY on
CONSTRUCTORs of const-qualified objects after they have been fully
constructed.  But I never made sure that what we're setting the flag
on actually is a CONSTRUCTOR.  Consequently, as this test case shows,
we could set TREE_READONLY on a VAR_DECL that in fact wasn't constant,
causing problems later.  Fixed by setting the flag on CONSTRUCTORs
only, and only when the evaluation produced something constant.

2020-02-19  Marek Polacek  <polacek@redhat.com>

	PR c++/93169 - wrong-code with a non-constexpr constructor.
	* constexpr.c (cxx_eval_call_expression): Only set TREE_READONLY
	on constant CONSTRUCTORs.

	* g++.dg/cpp0x/constexpr-93169.C: New test.

gcc/testsuite/ChangeLog:
	* gcc.dg/strlenopt-81.c: Align arrays to let strictly aligned targets
	optimize away calls as expected.

libstdc++-v3/ChangeLog:

	* testsuite/std/ranges/adaptors/split.cc (test03): Don't include the
	null terminator of the underlying string as part of the test_range.
	(main): Call test03.

	* include/bits/stl_iterator.h (common_iterator): Add copyable<I>
	requirement (LWG 3385).
	* testsuite/24_iterators/headers/iterator/synopsis_c++20.cc: Adjust
	expected declaration.

	* include/std/ranges (take_while_view, drop_view, drop_while_view)
	(elements_view:_Iterator): Initialize data members (LWG 3364).

This also removes a useless condition that was supposed to be removed by
the P1959R0 changes, but left in when that was implemented.

	* libsupc++/compare (three_way_comparable): Remove always-false check
	that should have been removed with weak_equality (P1959R0).
	(three_way_comparable_with): Likewise. Reorder requirements (LWG 3360).

	* include/std/concepts (__detail::__partially_ordered_with): Move here
	from <compare>.
	(totally_ordered, totally_ordered_with): Use __partially_ordered_with
	to simplify definition (LWG 3331).
	* libsupc++/compare (__detail::__partially_ordered_with): Move to
	<concepts>.

	* include/std/concepts (totally_ordered_with): Remove redundant
	requirement (LWG 3329).

	* include/std/ranges (__detail::__convertible_to_non_slicing): New
	helper concept.
	(__detail::__pair_like_convertible_to): Remove.
	(__detail::__pair_like_convertible_from): Add requirements for
	non-slicing conversions.
	(subrange): Constrain constructors with __convertible_to_non_slicing.
	Remove constructors from pair-like types. Add new deduction guide.
	* testsuite/std/ranges/subrange/lwg3282_neg.cc: New test.

	* include/bits/iterator_concepts.h (iter_move): Add declaration to
	prevent unqualified lookup finding a suitable declaration (LWG 3247).

	* gcc.dg/gimplefe-41.c: Add -msse2 additional options for x86 targets.
	* gcc.dg/ipa/ipa-sra-19.c: Ditto.

2020-02-19  Bernd Edlinger  <bernd.edlinger@hotmail.de>

        * collect2.c (maybe_run_lto_and_relink): Fix typo in
        comment.

	* include/std/memory_resource (polymorphic_allocator::allocate)
	(polymorphic_allocator::allocate_object): Change type of exception to
	bad_array_new_length (LWG 3237).
	* testsuite/20_util/polymorphic_allocator/lwg3237.cc: New test.

We already defined the traits in <type_traits> as now required by LWG
3348, but the macro was missing. This adds it.

	* include/std/type_traits (__cpp_lib_unwrap_ref): Define (LWG 3348).
	* include/std/version (__cpp_lib_unwrap_ref): Likewise.
	* testsuite/20_util/unwrap_reference/1.cc: Check macro.
	* testsuite/20_util/unwrap_reference/3.cc: New test.

	* include/std/numeric (midpoint(T8, T*)): Do not check for complete
	type during overload resolution, use static assert instead (LWG 3200).
	* testsuite/26_numerics/midpoint/pointer.cc: Do not test with
	incomplete type.
	* testsuite/26_numerics/midpoint/pointer_neg.cc: New test.

The 23_containers/span/deduction.cc test was already passing, but only
because I had previously implemented the original proposed resolution of
3255. As pointed out in 3255 that original P/R was incorrect because it
broke construction from array xvalues. This reverts the incorrect part
of 3255 (and adds tests for the case it broke), and implements the
resolution of 3369 instead.

	* include/std/span (span(T (&)[N])): Use non-deduced context to
	prevent first parameter from interfering with class template argument
	deduction (LWG 3369).
	* testsuite/23_containers/span/deduction.cc: Add missing 'const'.
	* testsuite/23_containers/span/lwg3255.cc: Check for construction from
	rvalues.

	* include/std/span (span::const_iterator, span::const_reverse_iterator)
	(span::cbegin(), span::cend(), span::crbegin(), span::crend()):
	Remove (LWG 3320).
	* testsuite/23_containers/span/everything.cc: Replace uses of cbegin
	and cend.
	* testsuite/20_util/specialized_algorithms/destroy/constrained.cc:
	Likewise.
	* testsuite/20_util/specialized_algorithms/uninitialized_copy/
	constrained.cc: Likewise.
	* testsuite/20_util/specialized_algorithms/
	uninitialized_default_construct/constrained.cc: Likewise.
	* testsuite/20_util/specialized_algorithms/uninitialized_fill/
	constrained.cc: Likewise.
	* testsuite/20_util/specialized_algorithms/uninitialized_move/
	constrained.cc: Likewise.
	* testsuite/20_util/specialized_algorithms/
	uninitialized_value_construct/constrained.cc: Likewise.

This PR is a regression caused by r256644, which added support for alias
checks involving variable strides.  One of the changes in that commit
was to split the access size out of the segment length.  The PR shows
that I hadn't done that correctly for the handling of negative strides
in vect_compile_time_alias.  The old code was:

      const_length_a = (-wi::to_poly_wide (segment_length_a)).force_uhwi ();
      offset_a = (offset_a + vect_get_scalar_dr_size (a)) - const_length_a;

where vect_get_scalar_dr_size (a) was cancelling out the subtraction
of the access size inherent in "- const_length_a".  Taking the access
size out of the segment length meant that the addition was no longer
needed/correct.

2020-02-19  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	PR tree-optimization/93767
	* tree-vect-data-refs.c (vect_compile_time_alias): Remove the
	access-size bias from the offset calculations for negative strides.

gcc/testsuite/
	PR tree-optimization/93767
	* gcc.dg/vect/pr93767.c: New test.

	* include/bits/range_access.h (range_size_t): Define alias template.
	* include/std/ranges (all_view): Rename to views::all_t (LWG 3335).
	* testsuite/std/ranges/adaptors/filter.cc: Adjust to new name.

	* include/std/ranges (filter_view, transform_view, take_view)
	(join_view, split_view, reverse_view): Remove commented-out converting
	constructors (LWG 3280).

	* include/std/memory (uninitialized_construct_using_allocator): Use
	std::construct_at (LWG 3321).

	* include/std/memory_resource (polymorphic_allocator::allocate_bytes)
	(polymorphic_allocator::allocate_object)
	(polymorphic_allocator::new_object): Add nodiscard attribute (LWG3304).

	* include/bits/range_access.h (enable_safe_range): Rename to
	enable_borrowed_range.
	(__detail::__maybe_safe_range): Rename to __maybe_borrowed_range.
	(safe_range): Rename to borrowed_range.
	* include/bits/ranges_algo.h: Adjust to use new names.
	* include/bits/ranges_algobase.h: Likewise.
	* include/bits/ranges_uninitialized.h: Likewise.
	* include/std/ranges: Likewise.
	(safe_iterator_t): Rename to borrowed_iterator_t.
	(safe_subrange_t): Rename to borrowed_subrange_t.
	* include/std/span: Adjust to use new names.
	* include/std/string_view: Likewise.
	* include/experimental/string_view: 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/end.cc: Likewise.
	* testsuite/std/ranges/access/rbegin.cc: Likewise.
	* testsuite/std/ranges/access/rend.cc: Likewise.
	* testsuite/std/ranges/safe_range.cc: Likewise.
	* testsuite/std/ranges/safe_range_types.cc: Likewise.
	* testsuite/util/testsuite_iterators.h: Likewise.

	* include/std/ranges (tuple_element<0, const subrange<I, S, K>>)
	(tuple_element<1, const subrange<I, S, K>>): Add partial
	specializations (LWG 3398).
	* testsuite/std/ranges/subrange/tuple_like.cc: New test.

Some of these casts were added by me the other day, but some were
already present. I think they are all redundant following the
introduction of the boolean-testable concept in P1964R2.

	* include/bits/ranges_algo.h (__find_fn, __find_first_of_fn)
	(__adjacent_find_fn, __remove_if_fn, __remove_copy_if_fn)
	(__unique_fn, __unique_copy_fn): Remove redundant conversions to bool.

And avoid signal handler calling signal unsafe functions,
and/or calling unlink with uninitialized memory pointer.

2020-02-19  Bernd Edlinger  <bernd.edlinger@hotmail.de>

	* collect2.c (c_file, o_file): Make const again.
	(ldout,lderrout, dump_ld_file): Remove.
	(tool_cleanup): Avoid calling not signal-safe functions.
	(maybe_run_lto_and_relink): Avoid possible signal handler
	access to unintialzed memory (lto_o_files).
	(main): Avoid leaking temp files in $TMPDIR.
	Initialize c_file/o_file with concat, which avoids exposing
	uninitialized memory to signal handler, which calls unlink(!).
	Avoid calling maybe_unlink when the main function returns,
	since the atexit handler is already doing this.
	* collect2.h (dump_ld_file, ldout, lderrout): Remove.

SRA can get a bit confused with zero-sized accesses like the one in
the testcase.  Since there is nothing in the access, nothing is
scalarized, but we can get order of the structures wrong, which the
verifier is not happy about.

Fixed by simply ignoring such accesses.

2020-02-19  Martin Jambor  <mjambor@suse.cz>

	PR tree-optimization/93776
	* tree-sra.c (create_access): Do not create zero size accesses.
	(get_access_for_expr): Do not search for zero sized accesses.

	testsuite/
	* gcc.dg/tree-ssa/pr93776.c: New test.

[[no_unique_address]] C++ attribute can cause two fields of a
RECORD_TYPE overlap, which currently confuses the totally scalarizing
code into creating invalid access tree.  For GCC 10, I'd like to
simply disable total scalarization of types where this happens.

For GCC 11 I'll write down a TODO item to enable total scalarization
of cases like this where the problematic fields are basically empty -
despite having a non-zero size - i.e. when they are just RECORD_TYPEs
without any data fields.

2020-02-19  Martin Jambor  <mjambor@suse.cz>

	gcc/

	PR tree-optimization/93667
	* tree-sra.c (scalarizable_type_p): Return false if record fields
	do not follow wach other.

	gcc/testsuite/

	PR tree-optimization/93667
	* g++.dg/tree-ssa/pr93667.C: New test.

2020-02-19  Tobias Burnus  <tobias@codesourcery.com>

	* .gitattributes: New; whitespace handling for Fortran's openacc_lib.h.
	* config/accel/openacc.f90 (openacc_kinds): Add acc_device_current.
	(openacc_internal, acc_on_device_h): Fix argument name; minor cleanup.
	* libgomp.texi (Enabling OpenACC): No longer mark as experimental.
	(acc_set_device_num): Fix Fortran argument name, use same name for C.
	(acc_get_property): Update Fortran interface to post-OpenACC 3.0
	corrections; add note about the previous interface and named constant.
	(OpenACC library and environment variables): Fix two typos.
	* openacc.f90: Use for all procedures the argument names from the spec
	as for …_h they are user visible.
	(openacc_kinds): Rename acc_device_property to
	acc_device_property_kinds and change value to int32 ; and update users.
	Re-add acc_device_property for for backward compatibility.
	(acc_get_property_string_h): Clean up as acc_device_property_kind
	changed.
	(acc_get_property_h): Likewise and return c_size_t instead of
	acc_device_property.
	(openacc): Also export acc_device_property_kinds.
	(acc_async_test_h, acc_async_test_all_h, acc_on_device_h,
	acc_is_present_32_h, acc_is_present_64_h): Simplify logical-return-value
	handling; check against /= 0 instead of == 1 to match C.
	* openacc_lib.h: Use for all procedures the argument names from the spec
	as for …_h they are user visible. Place !GCC$ into the first column to
	be active also for fixed-form souce form.
	(acc_device_current, acc_device_property_kind, acc_device_property,
	acc_property_memory, acc_property_free_memory, acc_property_name,
	acc_property_vendor, acc_property_driver): New named constants.
	(acc_get_property, acc_get_property_string): New generic interface.

 - fmv.x.s/fmv.s.x renamed to fmv.x.w/fmv.w.x in the latest RISC-V ISA
   manual.

 - Tested rv32gc/rv64gc on bare-metal with qemu.

ChangeLog

gcc/

Kito Cheng  <kito.cheng@sifive.com>

	* config/riscv/riscv.c (riscv_output_move) Using fmv.x.w/fmv.w.x
	rather than fmv.x.s/fmv.s.x.