Commit Graph

4381 Commits

Author SHA1 Message Date
Jonathan Wakely
a1a0dc4548 libstdc++: Remove noexcept from match_results comparisons (PR 94627)
These functions can't be noexcept because the iterators stored in the
sub_match objects can throw on any operation.

libstdc++-v3/ChangeLog:

	PR libstdc++/94627
	* include/bits/regex.h (operator==, operator!=): Remove noexcept
	equality comparisons for match_results.
	* testsuite/28_regex/match_results/94627.cc: New test.
2020-07-01 21:06:42 +01:00
Ville Voutilainen
2635f9e508 Revert "Add a __nonnnull__ attribute to std::string's _CharT* constructor"
This reverts commit b26fd416fb.
2020-06-30 01:59:34 +03:00
Ville Voutilainen
b26fd416fb Add a __nonnnull__ attribute to std::string's _CharT* constructor
Add a __nonnnull__ attribute to std::string's _CharT* constructor
	* include/bits/basic_string.h (string(_CharT*, const _Alloc&)):
	Add a __nonnull__ attribute.
	* testsuite/21_strings/basic_string/cons/char/nonnull.cc: New.
	* testsuite/21_strings/basic_string/cons/wchar_t/nonnull.cc: Likewise.
2020-06-29 00:47:05 +03:00
Jonathan Wakely
25920dd18a libstdc++: Fix warnings with -Wsystem-headers
libstdc++-v3/ChangeLog:

	* include/bits/stl_algobase.h (__find_if): Add FALLTHRU markers.
	* include/std/charconv (__detail::__to_chars): Avoid
	-Wsign-compare warning.
2020-06-24 12:34:17 +01:00
Jonathan Wakely
5b6215083b libstdc++: Fix some -Wsystem-headers warnings (PR 95765)
PR libstdc++/95765
	* include/bits/stl_algobase.h (__size_to_integer(float))
	(__size_to_integer(double), __size_to_integer(long double))
	(__size_to_integer(__float128)): Cast return type explicitly.
	* include/bits/stl_uninitialized.h (__uninitialized_default_1<true>):
	Remove unused typedef.
2020-06-19 18:20:05 +01:00
Jonathan Wakely
a7a3932e4b libstdc++: Remove redundant std:: qualification
* include/bits/stl_pair.h (_Index_tuple): Remove redundant
	namespace qualification.
	(pair::pair(tuple<>&, tuple<>&, _Index_tuple, _Index_tuple)):
	Likewise.
	* include/std/tuple (_Head_base, _Tuple_impl, tuple_size)
	(tuple_element, __get_helper, get, __make_tuple_impl)
	(__make_1st_indices, __tuple_concater)
	(pair::pair(tuple<>&, tuple<>&, _Index_tuple, _Index_tuple)):
	Likewise.
	* include/std/utility (tuple_element, __is_tuple_like_impl)
	(tuple_size, __pair_get, get): Likewise.
2020-06-19 15:02:54 +01:00
Jonathan Wakely
abed8b56b9 libstdc++: Define all std::function members inline
* include/bits/std_function.h (function): Define all member
	functions inline.
2020-06-19 14:37:52 +01:00
Marc Glisse
465520e3eb libstdc++: std::includes performance tweak
A small tweak to the implementation of __includes, which in my
application saves 20% of the running time. I noticed it because using
range-v3 was giving unexpected performance gains.

Some of the gain comes from pulling the 2 calls ++__first1 out of the
condition so there is just one call. And most of the gain comes from
replacing the resulting

if (__comp(__first1, __first2))
  ;
else
  ++__first2;

with

if (!__comp(__first1, __first2))
  ++__first2;

I was very surprised that the code ended up being so different for such
a change, and I still don't really understand where the extra time is
going...

Anyway, while I blame the compiler for not generating very good code
with the current implementation, I believe the change can be seen as a
simplification.

libstdc++-v3/ChangeLog:

	* include/bits/stl_algo.h (__includes): Simplify the code.
2020-06-19 13:03:45 +01:00
Jonathan Wakely
632183ddcc libstdc++: Avoid stack overflow in std::vector (PR 94540)
The std::__uninitialized_default_n algorithm used by std::vector creates
an initial object as a local variable then copies that into the
destination range. If the object is too large for the stack this
crashes. We should create the first object directly into the
destination and then copy it from there.

This doesn't fix the bug for C++98, because in that case the initial
value is created as a default argument of the vector constructor i.e. in
the user's code, not inside libstdc++. We can't prevent that.

	PR libstdc++/94540
	* include/bits/stl_uninitialized.h (__uninitialized_default_1<true>):
	Construct the first value at *__first instead of on the stack.
	(__uninitialized_default_n_1<true>): Likewise.
	Improve comments on several of the non-standard algorithms.
	* testsuite/20_util/specialized_algorithms/uninitialized_default/94540.cc:
	New test.
	* testsuite/20_util/specialized_algorithms/uninitialized_default_n/94540.cc:
	New test.
	* testsuite/20_util/specialized_algorithms/uninitialized_value_construct/94540.cc:
	New test.
	* testsuite/20_util/specialized_algorithms/uninitialized_value_construct_n/94540.cc:
	New test.
	* testsuite/23_containers/vector/cons/94540.cc: New test.
2020-06-17 22:49:06 +01:00
Jonathan Wakely
c9dce3b15e libstdc++: Handle non-integral sizes in std::uninitialized_fill_n
The std::uninitialized_fill_n algorithm uses sd::fill_n for trivial
types, but that algorithm has a stronger requirement that the Size
parameter is convertible to an integral type. As the new test shows,
there are types which are valid for std::uninitialized_fill_n but which
produce a different result when converted to an integral type, or cannot
be converted at all. Only use the std::fill_n optimization when the Size
type is already an integral type.

The std::__uninitialized_default_n extension has the same problem, and
so does C++17's std::uninitialized_value_construct_n which uses it.

	* include/bits/stl_uninitialized.h (uninitialized_fill_n): Only
	use std::fill_n when the size is an integral type.
	(__uninitialized_default_n): Likewise.
	* testsuite/20_util/specialized_algorithms/uninitialized_default_n/sizes.cc:
	New test.
	* testsuite/20_util/specialized_algorithms/uninitialized_fill_n/sizes.cc:
	New test.
	* testsuite/20_util/specialized_algorithms/uninitialized_value_construct_n/sizes.cc:
	New test.
2020-06-17 20:55:06 +01:00
Jonathan Wakely
e40b11a91c libstdc++: Strip cv-qualifiers in std::atomic<FP> (PR 95282)
This improves the previous fix for PR 95282, and extends it to also
apply to the exchange function (which has a similar problem and would
become ill-formed with my proposed fix for PR 95378).

	PR libstdc++/95282
	* include/bits/atomic_base.h (__atomic_impl::load): Use the _Val
	alias instead of deducing _Tp as an unqualified type.
	(__atomic_impl::exchange): Use the _Val alias to remove volatile
	from the reinterpret_cast result type.
2020-06-16 22:34:55 +01:00
Jonathan Wakely
b6ab9ecd55 libstdc++: Update value of __cpp_lib_constexpr_char_traits for C++20
Although not required by SD-6 or the C++20 draft, we define the macro
__cpp_lib_constexpr_char_traits to indicate support for P0432R1. This
updates the value in C++20 mode for the P1032R1 changes to char_traits.

	* include/bits/char_traits.h (__cpp_lib_constexpr_char_traits):
	Update value for C++20.
	* include/std/version (__cpp_lib_constexpr_char_traits): Likewise.
	* testsuite/21_strings/char_traits/requirements/constexpr_functions_c++17.cc:
	Update expected value.
	* testsuite/21_strings/char_traits/requirements/constexpr_functions_c++20.cc:
	Likewise.
2020-06-15 14:31:26 +01:00
Paul Keir
eb11134d0c libstdc++: Fix char_traits move with overlap
Upon constexpr evaluation, char_traits move uses copy_backward, but its
last argument should be to the range end rather than its beginning.

2020-06-12  Paul Keir  <paul.keir@uws.ac.uk>

	* include/bits/char_traits.h (char_traits::move): constexpr move with
	overlap was using copy_backward incorrectly.
	* testsuite/21_strings/char_traits/requirements/constexpr_functions_c++20.cc:
	New test.
2020-06-15 14:31:26 +01:00
Jonathan Wakely
17412a74c5 libstdc++: Make std::atomic_flag::test members const
Also fix the tests so they run without an explicit -std=gnu++2a in the
RUNTESTFLAGS, and test the new function on const-qualified objects.

	* include/bits/atomic_base.h (atomic_flag::test): Add missing
	const qualifiers.
	* testsuite/29_atomics/atomic_flag/test/explicit.cc: Add
	dg-options and verify results of test function.
	* testsuite/29_atomics/atomic_flag/test/implicit.cc: Likewise.
2020-06-12 10:31:07 +01:00
Jonathan Wakely
b32eea9c0c libstdc++: Fix istream::ignore discarding too many chars (PR 94749)
The current code assumes that if the next character in the stream is
equal to the delimiter then we stopped because we saw that delimiter,
and so discards it.  But in the testcase for the PR we stop because we
reached the maximum number of characters, and it's coincidence that the
next character equals the delimiter. We should not discard the next
character in that case.

The fix is to check that we haven't discarded __n characters already,
instead of checking whether the next character equals __delim. Because
we've already checked for EOF, if we haven't discarded __n yet then we
know we stopped because we saw the delimiter. On the other hand, if the
next character is the delimiter we don't know if that's why we stopped.

	PR libstdc++/94749
	* include/bits/istream.tcc (basic_istream::ignore(streamsize, CharT)):
	Only discard an extra character if we didn't already reach the
	maximum number.
	* src/c++98/istream.cc (istream::ignore(streamsiz, char))
	(wistream::ignore(streamsize, wchar_t)): Likewise.
	* testsuite/27_io/basic_istream/ignore/char/94749.cc: New test.
	* testsuite/27_io/basic_istream/ignore/wchar_t/94749.cc: New test.
2020-06-11 18:41:37 +01:00
Patrick Palka
a73051a0ea libstdc++: Fix some ranges algos optimizations [PR95578]
ranges::copy and a number of other ranges algorithms have unwrapping
optimizations for iterators of type __normal_iterator, move_iterator and
reverse_iterator.  But in the checks that guard these optimizations we
currently only test that the iterator of the iterator/sentinel pair has
the appropriate type before proceeding with the corresponding
optimization, and do not also test the sentinel type.

This breaks the testcase in this PR because this testcase constructs via
range adaptors a range whose begin() is a __normal_iterator and whose
end() is a custom sentinel type, and then performs ranges::copy on it.
From there we bogusly perform the __normal_iterator unwrapping
optimization on this iterator/sentinel pair, which immediately leads to
a constraint failure since the custom sentinel type does not model
sentinel_for<int*>.

This patch fixes this issue by refining each of the problematic checks
to also test that the iterator and sentinel types are the same before
applying the corresponding unwrapping optimization.  Along the way, some
code simplifications are made.

libstdc++-v3/ChangeLog:

	PR libstdc++/95578
	* include/bits/ranges_algo.h (__lexicographical_compare_fn):
	Also check that the iterator and sentinel have the same type before
	applying the unwrapping optimization for __normal_iterator.
	Split the check into two, one for the first iterator/sentinel
	pair and another for second iterator/sentinel pair.  Remove uses
	of __niter_base, and remove uses of std::move on a
	__normal_iterator.
	* include/bits/ranges_algobase.h (__equal_fn): Likewise.
	(__copy_or_move): Likewise.  Perform similar adjustments for
	the reverse_iterator and move_iterator optimizations.  Inline
	the checks into the if-constexprs, and use using-declarations to
	make them less visually noisy.  Remove uses of __niter_wrap.
	(__copy_or_move_backward): Likewise.
	* testsuite/25_algorithms/copy/95578.cc: New test.
	* testsuite/25_algorithms/copy_backward/95578.cc: New test.
	* testsuite/25_algorithms/equal/95578.cc: New test.
	* testsuite/25_algorithms/lexicographical_compare/95578.cc: New test.
	* testsuite/25_algorithms/move/95578.cc: New test.
	* testsuite/25_algorithms/move_backward/95578.cc: New test.
2020-06-10 17:37:53 -04:00
François Dumont
3a391adf7a libstdc++: Extend memcmp optimization in std::lexicographical_compare
Make the memcmp optimization work for std::deque iterators and safe
iterators.

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

libstdc++-v3/ChangeLog:

2020-06-08  François Dumont  <fdumont@gcc.gnu.org>
	    Jonathan Wakely  <jwakely@redhat.com>

	* include/bits/deque.tcc (__lex_cmp_dit): New.
	(__lexicographical_compare_aux1): Define overloads for deque
	iterators.
	* include/bits/stl_algobase.h (__lexicographical_compare::__3way):
	New static member function.
	(__lexicographical_compare<true>::__3way): Likewise.
	(__lexicographical_compare<true>::__lc): Use __3way.
	(__lexicographical_compare_aux): Rename to
	__lexicographical_compare_aux1 and declare overloads for deque
	iterators.
	(__lexicographical_compare_aux): Define new forwarding function
	that calls __lexicographical_compare_aux1 and declare new overloads
	for safe iterators.
	(lexicographical_compare): Do not use __niter_base on
	parameters.
	* include/debug/safe_iterator.tcc
	(__lexicographical_compare_aux): Define overloads for safe
	iterators.
	* testsuite/25_algorithms/lexicographical_compare/1.cc: Add
	checks with random access iterators.
	* testsuite/25_algorithms/lexicographical_compare/deque_iterators/1.cc:
	New test.
2020-06-10 17:48:56 +01:00
Jonathan Wakely
733167f9d5 libstdc++: Define converting assignment operator for std::move_iterator
As clarified by LWG 3265, std::move_iterator is supposed to have an
assignment operator that converts from a different specialization of
std::move_iterator, which performs an assignment. That has always been
missing from libstdc++, so assigning a different type actually performs
a converting construction, then an assignment. This is non-conforming
for the (fairly contrived) case where the converting assignment is
well-formed but the converting construction is not.

	* include/bits/stl_iterator.h (move_iterator::operator=): Define.
	* testsuite/24_iterators/move_iterator/dr3265.cc: New test.
2020-06-09 22:16:24 +01:00
Jonathan Wakely
187da2ce31 libstdc++: Implement operator<< for std::unique_ptr (LWG 2948)
libstdc++-v3/ChangeLog:

	* include/bits/unique_ptr.h (operator<<): Define for C++20.
	* testsuite/20_util/unique_ptr/io/lwg2948.cc: New test.
2020-06-08 21:21:31 +01:00
Jonathan Wakely
f2242ec0d3 libstdc++: Remove workarounds for constrained nested class templates
With PR c++/92078 and PR c++/92103 both fixed, nested class templates
can now be constrained. That means a number of namespace-scope helpers
can be moved to the class scope, so they're only visible where they're
needed.

	* include/bits/iterator_concepts.h (__detail::__ptr, __detail::__ref)
	(__detail::__cat, __detail::__diff): Move to class scope in the
	relevant __iterator_traits specializations.
	(__iterator_traits<>): Use nested class templates instead of ones from
	namespace __detail.
	* include/bits/stl_iterator.h (__detail::__common_iter_ptr): Move to
	class scope in iterator_traits<common_iterator<I, S>>.
	(iterator_traits<common_iterator<I, S>>): Use nested class template
	instead of __detail::__common_iter_ptr.
2020-06-04 23:20:49 +01:00
François Dumont
4e05c918d2 libstdc++: Specialize copy/copy_n for istreambuf_iterator and deque iterators
Add __copy_n_a overloads for std::deque iterators to replace with C memmove
when possible. Expose std::copy_n implementation details in pre-C++11 modes
and use it for std::copy overloads.

libstdc++-v3/ChangeLog

	* include/bits/stl_algo.h (__copy_n_a): Move to ...
	* include/bits/stl_algobase.h (__copy_n_a): ...here. Add __strict
	parameter.
	(__copy_n_a(istreambuf_iterator<>, _Size, _Deque_iterator<>, bool)):
	Declare.
	(__niter_base(const _Safe_iterator<_Ite, _Seq,
	random_access_iterator_tag>&)): Declare.
	(__copy_move_a2(istreambuf_iterator<>, istreambuf_iterator<>,
	_Deque_iterator<>)): Declare.
	* include/bits/deque.tcc
	(__copy_move_a2(istreambuf_iterator<>, istreambuf_iterator<>,
	_Deque_iterator<>)): New.
	(__copy_n_a(istreambuf_iterator<>, _Size, _Deque_iterator<>, bool)):
	New.
	* include/bits/streambuf_iterator.h
	(__copy_n_a(istreambuf_iterator<>, _Size, _CharT*, bool)): Adapt.
	* include/debug/safe_iterator.tcc (__niter_base): New.
	* testsuite/25_algorithms/copy/streambuf_iterators/char/4.cc
	(test03): New.
	* testsuite/25_algorithms/copy/streambuf_iterators/char/debug/deque_neg.cc:
	New test.
	* testsuite/25_algorithms/copy_n/debug/istreambuf_ite_deque_neg.cc:
	New test.
	* testsuite/25_algorithms/copy_n/istreambuf_iterator/2.cc: New test.
	* testsuite/25_algorithms/copy_n/istreambuf_iterator/deque.cc:
	New test.
2020-06-04 22:27:47 +02:00
Jonathan Wakely
e1008cd1d8 libstdc++: Make std::copy_n work with negative and non-integral sizes
Since it was added in C++11, std::copy_n and std::ranges::copy_n should
do nothing given a negative size, but for random access iterators we add
the size to the iterator, possibly resulting in undefined behaviour.

Also, C++20 clarified that std::copy_n requires the Size type to be
convertible to an integral type. We previously assumed that it could be
directly used in arithmetic expressions, without conversion to an
integral type.

This also fixes a bug in the random_access_iterator_wrapper helper adds
some convenience aliases for using the iterator wrappers.

libstdc++-v3/ChangeLog:

	* include/bits/ranges_algobase.h (__copy_n_fn): Only call
	ranges::copy for positive values.
	* include/bits/stl_algo.h (copy_n): Convert Size argument to an
	integral type and only call __copy_n for positive values.
	* testsuite/util/testsuite_iterators.h
	(random_access_iterator_wrapper::operator+=): Fix range check for
	negative values.
	(output_container, input_container, forward_container)
	(bidirectional_container, random_access_container): New alias
	templates.
	* testsuite/25_algorithms/copy_n/5.cc: New test.
2020-06-04 14:21:34 +01:00
Jonathan Wakely
cd3f067b82 libstdc++: Fix filesystem::u8path for mingw targets (PR 95392)
When I refactored filesystem::path string conversions in
r11-587-584d52b088f9fcf78704b504c3f1f07e17c1cded I failed to update the
mingw-specific code in filesystem::u8path, causing a bootstrap failure.

This fixes it, and further refactors the mingw-specific code along the
same lines as the previous commit. All conversions from UTF-8 strings to
wide strings now use the same helper function, __wstr_from_utf8.

	PR libstdc++/95392
	* include/bits/fs_path.h (path::_S_to_string): Move to
	namespace-scope and rename to ...
	(__detail::__string_from_range): ... this.
	[WINDOWS] (__detail::__wstr_from_utf8): New function template to
	convert a char sequence containing UTF-8 to wstring.
	(path::_S_convert(Iter, Iter)): Adjust call to _S_to_string.
	(path::_S_convert_loc(Iter, Iter, const locale&)): Likewise.
	(u8path(InputIterator, InputIterator)) [WINDOWS]: Use
	__string_from_range to obtain a contiguous range and
	__wstr_from_utf8 to obtain a wide string.
	(u8path(const Source&)) [WINDOWS]: Use __effective_range to
	obtain a contiguous range and __wstr_from_utf8 to obtain a wide
	string.
	(path::_S_convert(const _EcharT*, const _EcharT)) [WINDOWS]:
	Use __wstr_from_utf8.
2020-06-02 00:07:05 +01:00
François Dumont
7688e5e8c4 libstdc++: Review unordered_map insert_or_assign/try_emplace (PR 95079)
Those methods are making a double lookup in case of insertion, they can
perform only one.

	PR libstdc++/95079
	* include/bits/hashtable_policy.h (_Insert_base<>::try_emplace): New.
	* include/bits/unordered_map.h (unordered_map<>::try_emplace): Adapt.
	(unordered_map<>::insert_or_assign): Adapt.
2020-05-29 13:12:36 +02:00
Jonathan Wakely
bbaec68c86 libstdc++: Fix atomic<FP>::load (PR 95282)
PR libstdc++/95282
	* include/bits/atomic_base.h (__atomic_impl::load): Add
	cv-qualifiers to parameter so that _Tp is deduced as the
	unqualified type.
	* testsuite/29_atomics/atomic_float/95282.cc: New test.
2020-05-27 22:55:21 +01:00
Jonathan Wakely
979e89a9a9 libstdc++: Fix std::reverse_iterator comparisons (PR 94354)
The std::reverse_iterator comparisons have always been implemented only
in terms of equality and less than. In C++98 that made no difference for
reasonable code, because when the underlying operators are the same type
they are required to support all comparisons anyway.

But since LWG 280 it's possible to compare reverse_iterator<X> and
reverse_iterator<Y>, and comparisons between X and Y might not support
the full set of equality and relational operators. This means that it
matters whether we implement operator!= as x.base() != y.base() or
!(x.base() == y.base()), and the current implementation is
non-conforming.

This was already fixed in GCC 10.1 for C++20, this change also fixes it
for all other -std modes.

	PR libstdc++/94354
	* include/bits/stl_iterator.h (reverse_iterator): Fix comparison
	operators to use the correct operations on the underlying
	iterators.
	* testsuite/24_iterators/reverse_iterator/rel_ops.cc: New test.
2020-05-27 21:58:56 +01:00
Patrick Palka
3bf5e7657b libstdc++: Fix common_iterator::operator-> [PR95322]
This patch fixes the definition of common_iterator::operator-> when the
underlying iterator's operator* returns a non-reference.

The first problem is that the class __detail::_Common_iter_proxy is used
unqualified.  Fixing that revealed another problem: the class's template
friend declaration of common_iterator doesn't match up with the
definition of common_iterator, because the friend declaration isn't
constrained.

If we try to make the friend declaration match up by adding constraints,
we run into frontend bug PR93467.  So we currently can't correctly
express this friend relation between __detail::_Common_iter_proxy and
common_iterator.

As a workaround to this frontend bug, this patch moves the definition of
_Common_iter_proxy into the class template of common_iterator so that we
could instead express the friend relation via the injected-class-name.

(This bug was found when attempting to use views::common to work around
the compile failure with the testcase in PR95322.)

libstdc++-v3/ChangeLog:

	PR libstdc++/95322
	* include/bits/stl_iterator.h (__detail::_Common_iter_proxy):
	Remove and instead define it ...
	(common_iterator::_Proxy): ... here.
	(common_iterator::operator->): Use it.
	* testsuite/24_iterators/common_iterator/2.cc: New test.
	* testsuite/std/ranges/adaptors/95322.cc: New test.
2020-05-26 16:17:34 -04:00
Jonathan Wakely
584d52b088 libstdc++: Refactor filesystem::path string conversions
This simplifies the logic of converting Source arguments and pairs of
InputIterator arguments into the native string format. For any input
that is a contiguous range of path::value_type (or char8_t for POSIX)
a string view can be created and the conversion can be done directly,
with no intermediate allocation. Previously some cases created a
basic_string unnecessarily, for example construction from a pair of
path::string_type::iterators, or a pair of non-const value_type*
pointers.

	* include/bits/fs_path.h (__detail::_S_range_begin)
	(__detail::_S_range_end, path::_S_string_from_iter): Replace with
	overloaded function template __detail::__effective_range.
	(__detail::__effective_range): New overloaded function template to
	create a basic_string or basic_string_view for an effective range.
	(__detail::__value_type_is_char): Use __detail::__effective_range.
	Do not use remove_const on value type.
	(__detail::__value_type_is_char_or_char8_t): Likewise.
	(path::path(const Source&, format))
	(path::path(const Source&, const locale&))
	(path::operator/=(const Source&), path::append(const Source&))
	(path::concat(const Source&)): Use __detail::__effective_range.
	(path::_S_to_string(InputIterator, InputIterator)): New function
	template to create a string view if possible, or string otherwise.
	(path::_S_convert): Add overloads that convert a string returned
	by __detail::__effective_range. Use if-constexpr to inline conversion
	logic from all overloads of _Cvt::_S_convert.
	(path::_S_convert_loc): Add overload that converts a string. Use
	_S_to_string to avoid allocation when possible.
	(path::_Cvt): Remove.
	(path::operator+=(CharT)): Remove indirection through path::concat.
	* include/experimental/bits/fs_path.h (path::_S_convert_loc): Add
	overload for non-const pointers, to avoid constructing a std::string.
	* src/c++17/fs_path.cc (path::_S_convert_loc): Replace conditional
	compilation with call to _S_convert.
2020-05-23 09:40:16 +01:00
Jonathan Wakely
00c8f2a5e3 libstdc++: Remove incorrect static specifiers
These functions were originally static members of the path class, but
the 'static' specifiers were not removed when they were moved to
namespace scope. This causes ODR violations when the functions are
called from functions defined in the header, which is incompatible with
Nathan's modules branch.  Change them to 'inline' instead.

	* include/bits/fs_path.h (__detail::_S_range_begin)
	(__detail::_S_range_end): Remove unintentional static specifiers.
	* include/experimental/bits/fs_path.h (__detail::_S_range_begin)
	(__detail::_S_range_end): Likewise.
2020-05-23 09:40:16 +01:00
Jonathan Wakely
988b853f9c libstdc++: Simplify filesystem::path SFINAE constraints
This replaces the filesystem::__detail::_Path SFINAE helper with two
separate helpers, _Path and _Path2. This avoids having one helper which
tries to check two different sets of requirements.

The _Path helper now uses variable templates instead of a set of
overloaded functions to detect specializations of basic_string or
basic_string_view.

The __not_<is_void<remove_pointer_t<_Tp1>> check is not necessary in
C++20 because iterator_traits<void*> is now empty. For C++17 replace
that check with a __safe_iterator_traits helper with partial
specializations for void pointers.

Finally, the __is_encoded_char check no longer uses remove_const_t,
which means that iterators with a const value_type will no longer be
accepted as arguments for path creation. Such iterators resulted in
undefined behaviour anyway, so it's still conforming to reject them in
the constraint checks.

	* include/bits/fs_path.h (filesystem::__detail::__is_encoded_char):
	Replace alias template with variable template. Don't remove const.
	(filesystem::__detail::__is_path_src): Replace overloaded function
	template with variable template and specializations.
	(filesystem::__detail::__is_path_iter_src): Replace alias template
	with class template.
	(filesystem::__detail::_Path): Use __is_path_src. Remove support for
	iterator pairs.
	(filesystem::__detail::_Path2): New alias template for checking
	InputIterator requirements.
	(filesystem::__detail::__constructible_from): Remove.
	(filesystem::path): Replace _Path<Iter, Iter> with _Path2<Iter>.
	* testsuite/27_io/filesystem/path/construct/80762.cc: Check with two
	constructor arguments of void and void* types.
2020-05-23 09:40:16 +01:00
Jonathan Wakely
f094665d46 libstdc++: Avoid constraint recursion with iterator_traits (PR 93983)
Checking whether a filesystem::path constructor argument is an iterator
requires instantiating std::iterator_traits. In C++20 that checks for
satisfaction of std::iterator_traits constraints, which checks if the
type is copyable, which can end up recursing back to the path
constructor. The fix in LWG 3420 is to reorder the cpp17-iterator
concept's constraints to check if the type looks vaguely like an
iterator before checking copyable. That avoids the recursion for types
which definitely aren't iterators, but isn't foolproof.

	PR libstdc++/93983
	* include/bits/iterator_concepts.h (__detail::__cpp17_iterator):
	Reorder constraints to avoid recursion when constructors use
	iterator_traits (LWG 3420).
	* testsuite/24_iterators/customization_points/lwg3420.cc: New test.
2020-05-21 07:32:15 +01:00
Ulrich Drepper
491ba663e0 Implent C++20 std::atomic_flag::test
* include/bits/atomic_base.h (atomic_flag): Implement test member
        function.
        * include/std/version: Define __cpp_lib_atomic_flag_test.
        * testsuite/29_atomics/atomic_flag/test/explicit.cc: New file.
        * testsuite/29_atomics/atomic_flag/test/implicit.cc: New file.
2020-05-12 07:37:09 +02:00
Jonathan Wakely
9c24e97a97 libstdc++: Fix some C++20 algorithms to work in parallel mode
Some new algorithms need to use _GLIBCXX_STD_A to refer to the "normal"
version of the algorithm, to workaround the namespace dance done for
parallel mode.

	PR libstdc++/94971 (partial)
	* include/bits/ranges_algo.h (ranges::__sample_fn): Qualify
	std::sample using macro to work in parallel mode.
	(__sort_fn): Likewise for std::sort.
	(ranges::__nth_element_fn): Likewise for std::nth_element.
	* include/bits/stl_algobase.h (lexicographical_compare_three_way):
	Likewise for std::__min_cmp.
	* include/parallel/algobase.h (lexicographical_compare_three_way):
	Add to namespace std::__parallel.
2020-05-07 21:43:49 +01:00
François Dumont
72a54e5e81 libstdc++ std::fill overload for std::vector<bool>::iterator
Extend the overload so that it is used even when _GLIBCXX_DEBUG mode
is activated.

	* include/bits/stl_algobase.h (struct _Bit_iterator): New declaration.
	(std::__fill_a1(_Bit_iterator, _Bit_iterator, const bool&)): Likewise.
	* include/bits/stl_bvector.h (__fill_bvector): Move outside
	_GLIBCXX_STD_C namespace.
	(fill(_Bit_iterator, _Bit_iterator, const bool&)): Likewise and rename
	into...
	(__fill_a1): ...this.
	* testsuite/25_algorithms/fill/bvector/1.cc: New.
2020-05-06 23:28:22 +02:00
Jonathan Wakely
22b6b5d6cf libstdc++: Make byte-sized std::fill_n a constant expression (PR 94933)
The overload for byte types uses memset and isn't constexpr. This adds
the specifier and uses std::is_constant_evaluated() to provide a
compile-time alternative.

	PR libstdc++/94933
	* include/bits/stl_algobase.h (__fill_a1): Make overload for byte types
	usable in constant expressions.
	* testsuite/25_algorithms/fill_n/constexpr.cc: Test with bytes and
	non-scalars.
2020-05-03 13:33:15 +01:00
Jonathan Wakely
a5f2fb1ff1 libstdc++: Replace deduced return type in ranges::iter_move (PR 92894)
The deduced return type causes the instantiation of the function body,
which can then require the instantiation of std::projected::operator*
which is intentionally not defined.

This patch uses a helper trait to define the return type, so that the
function body doesn't need to be instantiated. That helper trait can
then also be used in other places that currently check the return type
of ranges::iter_move (iter_rvalue_reference_t and indirectly_readable).

2020-05-01  Jonathan Wakely  <jwakely@redhat.com>
	    Patrick Palka  <ppalka@redhat.com>

	PR libstdc++/92894
	* include/bits/iterator_concepts.h (ranges::__cust_imove::_IMove):
	Add trait to determine return type and an alias for it.
	(ranges::__cust_imove::_IMove::operator()): Use __result instead of
	deduced return type.
	(iter_rvalue_reference_t): Use _IMove::__type instead of checking
	the result of ranges::iter_move.
	(__detail::__indirectly_readable_impl): Use iter_rvalue_reference_t
	instead of checking the result of ranges::iter_move.
	* testsuite/24_iterators/customization_points/92894.cc: New test.
	* testsuite/24_iterators/indirect_callable/92894.cc: New test.
2020-05-01 14:27:25 +01:00
Jonathan Wakely
b1983f4582 libstdc++: Avoid errors in allocator's noexcept-specifier (PR 89510)
This fixes a regression due to the conditional noexcept-specifier on
std::allocator::construct and std::allocator::destroy, as well as the
corresponding members of new_allocator, malloc_allocator, and
allocator_traits. Those noexcept-specifiers were using expressions which
might be ill-formed, which caused errors outside the immediate context
when checking for the presence of construct and destroy in SFINAE
contexts.

The fix is to use the is_nothrow_constructible and
is_nothrow_destructible type traits instead, because those traits are
safe to use even when the construction/destruction itself is not valid.

The is_nothrow_constructible trait will be false for a type that is not
also nothrow-destructible, even if the new-expression used in the
construct function body is actually noexcept. That's not the correct
answer, but isn't a problem because providing a noexcept-specifier on
these functions is not required by the standard anyway. If the answer is
false when it should be true, that's suboptimal but OK (unlike giving
errors for valid code, or giving a true answer when it should be false).

	PR libstdc++/89510
	* include/bits/alloc_traits.h (allocator_traits::_S_construct)
	(allocator_traits::_S_destroy)
	(allocator_traits<allocator<T>>::construct): Use traits in
	noexcept-specifiers.
	* include/bits/allocator.h (allocator<void>::construct)
	(allocator<void>::destroy): Likewise.
	* include/ext/malloc_allocator.h (malloc_allocator::construct)
	(malloc_allocator::destroy): Likewise.
	* include/ext/new_allocator.h (new_allocator::construct)
	(new_allocator::destroy): Likewise.
	* testsuite/20_util/allocator/89510.cc: New test.
	* testsuite/ext/malloc_allocator/89510.cc: New test.
	* testsuite/ext/new_allocator/89510.cc: New test.
2020-04-30 16:01:43 +01:00
Jonathan Wakely
8f1591763f libstdc++: Fix outdated comment about std::string instantiations (PR 94854)
PR libstdc++/94854
	* include/bits/basic_string.tcc: Update comment about explicit
	instantiations.
2020-04-29 19:00:58 +01:00
Jonathan Wakely
d0330a0360 libstdc++: Fixes for feature test macros (PR 91480)
Remove the non-standard __cpp_lib_allocator_is_always_equal macro and
add the missing macros for P1032R1.

	PR libstdc++/91480
	* include/bits/allocator.h (__cpp_lib_allocator_is_always_equal):
	Remove non-standard macro.
	* include/bits/stl_iterator.h (__cpp_lib_constexpr_iterator): Define
	to indicate P1032R1 support.
	* include/bits/stl_pair.h (__cpp_lib_constexpr_utility): Likewise.
	* include/std/string_view (__cpp_lib_constexpr_string_view): Likewise.
	* include/std/tuple (__cpp_lib_constexpr_tuple): Likewise.
	* include/std/version (__cpp_lib_allocator_is_always_equal): Remove.
	(__cpp_lib_constexpr_iterator, __cpp_lib_constexpr_string_view)
	(__cpp_lib_constexpr_tuple, __cpp_lib_constexpr_utility): Define.
	* testsuite/20_util/function_objects/constexpr_searcher.cc: Check
	feature test macro.
	* testsuite/20_util/tuple/cons/constexpr_allocator_arg_t.cc: Likewise.
	* testsuite/21_strings/basic_string_view/operations/copy/char/
	constexpr.cc: Likewise.
	* testsuite/24_iterators/insert_iterator/constexpr.cc: Likewise.
2020-04-28 23:40:18 +01:00
Jonathan Wakely
162c40a4c1 libstdc++: Fix regression in std::_Construct (PR 94831)
By trying to reuse the existing std::_Construct function as a wrapper
for std::construct_at I introduced regressions, because changing
std::_Construct to return non-void made it ill-formed for array types.

The solution is to revert _Construct to its former state, and change
allocator_traits::construct to explicitly call construct_at instead.
This decouples all the existing callers of _Construct from the new
construct_at requirements.

	PR libstdc++/94831
	* include/bits/alloc_traits.h (_S_construct): Restore placement
	new-expression for C++11/14/17 and call std::construct_at directly
	for C++20.
	* include/bits/stl_construct.h (_Construct): Revert to non-constexpr
	function returning void.
	* testsuite/20_util/specialized_algorithms/
	uninitialized_value_construct/94831.cc: New test.
	* testsuite/23_containers/vector/cons/94831.cc: New test.
2020-04-28 23:39:38 +01:00
Jonathan Wakely
40541efe1c libstdc++: Change __cpp_lib_array_constexpr for C++17 again
This partially reverts my previous change related to this macro. The
C++20 constexpr iterator requirements are always met by array:iterator,
because it's just a pointer. So the macro can be set to 201803 even in
C++17 mode.

	* include/bits/stl_iterator.h (__cpp_lib_array_constexpr): Revert
	value for C++17 to 201803L because P0858R0 is supported for C++17.
	* include/std/version (__cpp_lib_array_constexpr): Likewise.
	* testsuite/23_containers/array/element_access/constexpr_c++17.cc:
	Check for value corresponding to P0031R0 features being tested.
	* testsuite/23_containers/array/requirements/constexpr_iter.cc:
	Check for value corresponding to P0858R0 features being tested.
2020-04-23 21:39:33 +01:00
Jonathan Wakely
e851aa1703 libstdc++: Update (and revert) value of __cpp_lib_array_constexpr
This macro should have been updated to 201811 when the last C++20
changes were implemented. However those changes are not enabled for
C++17 mode, so the macro should only have the new value in C++20 mode.

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

	* include/bits/stl_iterator.h (__cpp_lib_array_constexpr): Define
	different values for C++17 and C++20, to indicate different feature
	sets. Update value for C++20 to indicate P1032R1 support.
	* include/std/version (__cpp_lib_array_constexpr): Likewise.
	* testsuite/23_containers/array/comparison_operators/constexpr.cc:
	Check feature test macro.
	* testsuite/23_containers/array/element_access/constexpr_c++17.cc:
	New test.
	* testsuite/23_containers/array/requirements/constexpr_fill.cc: Check
	feature test macro.
	* testsuite/23_containers/array/requirements/constexpr_iter.cc: Test
	in C++17 mode and check feature test macro.
2020-04-22 22:54:35 +01:00
Jonathan Wakely
56772f623e libstdc++: Add missing feature test macros
These macros all correspond to features that are already supported, but
the macro was not defined when the feature was implemented.

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

	* include/bits/stl_map.h (__cpp_lib_map_insertion): Remove old
	macro.
	* include/bits/unordered_map.h (__cpp_lib_unordered_map_insertion):
	Likewise.
	* include/std/version (__cpp_lib_map_insertion)
	(__cpp_lib_unordered_map_insertion): Remove.
2020-04-22 22:54:34 +01:00
Jonathan Wakely
87841658d4 libstdc++: Fix __normal_iterator comparisons for C++20
This fixes a regression introduced when I replaced __normal_iterator's
relational operators with operator<=>. If the wrapped iterator type
doesn't define operator<=> then __normal_iterator doesdn't either, which
breaks any use of fancy pointers that don't define <=>. The regression
was found when trying to build cmcstl2.

The solution is to use synth-three-way to define __normal_iterator's
spaceship operator, so that it is still defined even if the wrapped type
only supports operator<.

	* include/bits/stl_iterator.h (__normal_iterator): Use synth-three-way
	to define operator<=>.
	* testsuite/24_iterators/normal_iterator/cmp_c++20.cc: New test.
2020-04-21 23:46:54 +01:00
Jonathan Wakely
93843da697 libstdc++: Add comparison operators to associative containers
The last C++20 changes from P1614R2, "The Mothership has Landed"

	* include/bits/stl_map.h (map): Define operator<=> and remove
	operator< for C++20.
	* include/bits/stl_multimap.h (multimap): Likewise.
	* include/bits/stl_multiset.h (multiset): Likewise.
	* include/bits/stl_set.h (set): Likewise.
	* include/bits/stl_tree.h (_Rb_tree): Likewise.
	(_Rb_tree_iterator, _Rb_tree_const_iterator): Remove redundant
	operator!= for C++20.
	* include/debug/map.h (__gnu_debug::map): Define operator<=> for C++20.
	* include/debug/multimap.h (__gnu_debug::multimap): Likewise.
	* include/debug/multiset.h (__gnu_debug::multiset): Likewise.
	* include/debug/set.h (__gnu_debug::set): Likewise.
	* testsuite/23_containers/map/operators/cmp_c++20.cc: New test.
	* testsuite/23_containers/multimap/operators/cmp_c++20.cc: New test.
	* testsuite/23_containers/multiset/operators/cmp_c++20.cc: New test.
	* testsuite/23_containers/set/operators/cmp_c++20.cc: New test.
2020-04-20 17:50:10 +01:00
Jonathan Wakely
717e91dbc4 libstdc++: Define operator<=> for std::stack and std::queue
Some more C++20 changes from P1614R2, "The Mothership has Landed".

	* include/bits/stl_queue.h (queue): Define operator<=> for C++20.
	* include/bits/stl_stack.h (stack): Likewise.
	* testsuite/23_containers/queue/cmp_c++20.cc: New test.
	* testsuite/23_containers/stack/cmp_c++20.cc: New test.
2020-04-19 21:30:15 +01:00
Jonathan Wakely
7ab9c2430f libstdc++: Remove operator!= overloads for unordered containers
Some more C++20 changes from P1614R2, "The Mothership has Landed".

	* include/bits/unordered_map.h (unordered_map, unordered_multimap):
	Remove redundant operator!= for C++20.
	* include/bits/unordered_set.h (unordered_set, unordered_multiset):
	Likewise.
	* include/debug/unordered_map (unordered_map, unordered_multimap):
	Likewise.
	* include/debug/unordered_set (unordered_set, unordered_multiset):
	Likewise.
2020-04-19 21:05:32 +01:00
Jonathan Wakely
bd2420f8fa libstdc++: Add comparison operators to sequence containers
Some more C++20 changes from P1614R2, "The Mothership has Landed".

This implements <=> for sequence containers (and the __normal_iterator
and _Pointer_adapter class templates).

	* include/bits/forward_list.h (forward_list): Define operator<=> and
	remove redundant comparison operators for C++20.
	* include/bits/stl_bvector.h (vector<bool, Alloc>): Likewise.
	* include/bits/stl_deque.h (deque): Likewise.
	* include/bits/stl_iterator.h (__normal_iterator): Likewise.
	* include/bits/stl_list.h (list): Likewise.
	* include/bits/stl_vector.h (vector): Likewise.
	* include/debug/deque (__gnu_debug::deque): Likewise.
	* include/debug/forward_list (__gnu_debug::forward_list): Likewise.
	* include/debug/list (__gnu_debug::list): Likewise.
	* include/debug/safe_iterator.h (__gnu_debug::_Safe_iterator):
	Likewise.
	* include/debug/vector (__gnu_debug::vector): Likewise.
	* include/ext/pointer.h (__gnu_cxx::_Pointer_adapter): Define
	operator<=> for C++20.
	* testsuite/23_containers/deque/operators/cmp_c++20.cc: New test.
	* testsuite/23_containers/forward_list/cmp_c++20.cc: New test.
	* testsuite/23_containers/list/cmp_c++20.cc: New test.
	* testsuite/23_containers/vector/bool/cmp_c++20.cc: New test.
	* testsuite/23_containers/vector/cmp_c++20.cc: New test.
2020-04-17 23:41:04 +01:00
Jonathan Wakely
875d6cb3b4 libstdc++: Add comparison operators for string and regex types
Some more C++20 changes from P1614R2, "The Mothership has Landed".

This adds three-way comparison support to std::char_traits,
std::basic_string, std::basic_string_view, and std::sub_match.

	* include/bits/basic_string.h (basic_string): Define operator<=> and
	remove redundant comparison operators for C++20.
	* include/bits/char_traits.h (__gnu_cxx::char_traits, char_traits):
	Add comparison_category members.
	(__detail::__char_traits_cmp_cat): New helper to get comparison
	category from char traits class.
	* include/bits/regex.h (regex_traits::_RegexMask::operator!=): Do not
	define for C++20.
	(sub_match): Define operator<=> and remove redundant comparison
	operators for C++20.
	(match_results): Remove redundant operator!= for C++20.
	* include/std/string_view (basic_string_view): Define operator<=> and
	remove redundant comparison operators for C++20.
	* testsuite/21_strings/basic_string/operators/char/cmp_c++20.cc: New
	test.
	* testsuite/21_strings/basic_string/operators/wchar_t/cmp_c++20.cc:
	New test.
	* testsuite/21_strings/basic_string_view/operations/copy/char/
	constexpr.cc: Initialize variable.
	* testsuite/21_strings/basic_string_view/operations/copy/wchar_t/
	constexpr.cc: Likewise.
	* testsuite/21_strings/basic_string_view/operators/char/2.cc: Add
	dg-do directive and remove comments showing incorrect signatures.
	* testsuite/21_strings/basic_string_view/operators/wchar_t/2.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operators/char/cmp_c++20.cc:
	New test.
	* testsuite/21_strings/basic_string_view/operators/wchar_t/cmp_c++20.cc:
	New test.
	* testsuite/28_regex/sub_match/compare_c++20.cc: New test.
2020-04-17 16:40:11 +01:00