4664 Commits

Author SHA1 Message Date
Jonathan Wakely
b59be1adba libstdc++: Simplify std::basic_regex construction and assignment
Introduce a new _M_compile function which does the common work needed by
all constructors and assignment. Call that directly to avoid multiple
levels of constructor delegation or calls to basic_regex::assign
overloads.

For assignment, there is no need to construct a std::basic_string if we
already have a contiguous sequence of the correct character type, and no
need to construct a temporary basic_regex when assigning from an
existing basic_regex.

Also define the copy and move assignment operators as defaulted, which
does the right thing without constructing a temporary and swapping it.
Copying or moving the shared_ptr member cannot fail, so they can be
noexcept. The assign(const basic_regex&) and assign(basic_regex&&)
member can then be defined in terms of copy or move assignment.

The new _M_compile function takes pointer arguments, so the caller has
to convert arbitrary iterator ranges into a contiguous sequence of
characters. With that simplification, the __compile_nfa helpers are not
needed and can be removed.

This also fixes a bug where construction from a contiguous sequence with
the wrong character type would fail to compile, rather than converting
the elements to the regex character type.

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

libstdc++-v3/ChangeLog:

	* 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.
2021-09-29 13:48:02 +01:00
Jonathan Wakely
2fcfc7d668 libstdc++: Fix return values for atomic wait on futex
This fixes a logic error in the futex-based timed wait.

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

libstdc++-v3/ChangeLog:

	* include/bits/atomic_timed_wait.h (__platform_wait_until_impl):
	Return false for ETIMEDOUT and true otherwise.
2021-09-28 21:27:04 +01:00
Jonathan Wakely
c44c5f3d9f libstdc++: Remove obfuscating typedefs in <regex>
There is no benefit to using _SizeT instead of size_t, and IterT tells
you less about the type than const _CharT*. This removes some unhelpful
typedefs.

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

libstdc++-v3/ChangeLog:

	* 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 20:38:58 +01:00
Jonathan Wakely
b5f276b8c7 libstdc++: Tweaks to <regex> to avoid warnings
Signed-off-by: Jonathan Wakely <jwakely@redhat.com>

libstdc++-v3/ChangeLog:

	* include/bits/regex_compiler.tcc: Add line break in empty while
	statement.
	* include/bits/regex_executor.tcc: Avoid unused parameter
	warning.
2021-09-28 20:38:58 +01:00
Jonathan Wakely
df0dd04b78 libstdc++: Add noexcept to functions in <regex>
Signed-off-by: Jonathan Wakely <jwakely@redhat.com>

libstdc++-v3/ChangeLog:

	* 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 20:38:57 +01:00
Jonathan Wakely
aeaea265ce libstdc++: Define macro before it is first checked
Signed-off-by: Jonathan Wakely <jwakely@redhat.com>

libstdc++-v3/ChangeLog:

	* include/bits/atomic_wait.h (_GLIBCXX_HAVE_PLATFORM_WAIT):
	Define before first attempt to check it.
2021-09-28 20:30:59 +01:00
Jonathan Wakely
afffc96a52 libstdc++: Fix concept checks for iterators
This adds some additional checks the the C++98-style concept checks for
iterators, and removes some bogus checks for mutable iterators. Instead
of requiring that the result of dereferencing a mutable iterator is
assignable (which is a property of the value type, not required for the
iterator) check that the reference type is a non-const reference to the
value type.

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

libstdc++-v3/ChangeLog:

	* 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 20:22:51 +01:00
Jonathan Wakely
45a8cd2569 libstdc++: Fix _OutputIteratorConcept checks in algorithms
The _OutputIteratorConcept should be checked using the correct value
category. The std::move_backward and std::copy_backward algorithms
should use _OutputIteratorConcept instead of _ConvertibleConcept.

In order to use the correct value category, the concept should use a
function that returns _ValueT instead of using an lvalue data member.

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

libstdc++-v3/ChangeLog:

	* 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 20:22:50 +01:00
Jonathan Wakely
82626be2d6 libstdc++: Specialize std::pointer_traits<__normal_iterator<I,C>>
This allows std::__to_address to be used with __normal_iterator in
C++11/14/17 modes. Without the partial specialization the deduced
pointer_traits::element_type is incorrect, and so the return type of
__to_address is wrong.

A similar partial specialization is probably needed for
__gnu_debug::_Safe_iterator.

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

libstdc++-v3/ChangeLog:

	* 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 20:22:50 +01:00
Jonathan Wakely
a11052d98d libstdc++: Improve std::forward static assert message
The previous message told you something was wrong, but not why it
happened or why it's bad. This changes it to explain that the function
is being misused.

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

libstdc++-v3/ChangeLog:

	* 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 17:30:05 +01:00
Jonathan Wakely
f2b7f56a15 libstdc++: Fix mismatched noexcept-specifiers in filesystem::path [PR102499]
Signed-off-by: Jonathan Wakely <jwakely@redhat.com>

libstdc++-v3/ChangeLog:

	PR libstdc++/102499
	* include/bits/fs_path.h (path::begin, path::end): Add noexcept
	to declarations, to match definitions.
2021-09-28 17:30:05 +01:00
Jonathan Wakely
9b11107ed7 libstdc++: Remove redundant 'inline' specifiers
These functions are constexpr, which means they are implicitly inline.

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

libstdc++-v3/ChangeLog:

	* include/bits/range_access.h (cbegin, cend): Remove redundant
	'inline' specifier.
2021-09-24 15:38:44 +01:00
Jonathan Wakely
42eff613d0 libstdc++: Add 'noexcept' to path::iterator members
All path::iterator operations are non-throwing.

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

libstdc++-v3/ChangeLog:

	* 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 20:43:34 +01:00
Jonathan Wakely
21c760510d libstdc++: Remove non-deducible parameter for std::advance overload
This was just a copy and paste error.

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

libstdc++-v3/ChangeLog:

	* include/bits/fs_path.h (advance): Remove non-deducible
	template parameter.
2021-09-16 23:06:37 +01:00
Jonathan Wakely
9d813ddd97 libstdc++: Add noexcept to std::to_string overloads that don't allocate
When the values is guaranteed to fit in the SSO buffer we know the
string won't allocate, so the function can be noexcept. For 32-bit
integers, we know they need no more than 9 bytes (or 10 with a minus
sign) and the SSO buffer is 15 bytes.

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

libstdc++-v3/ChangeLog:

	* 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 22:59:47 +01:00
Jonathan Wakely
869107c9c9 libstdc++: Add noexcept to unique_ptr accessors
Signed-off-by: Jonathan Wakely <jwakely@redhat.com>

libstdc++-v3/ChangeLog:

	* include/bits/unique_ptr.h (__uniq_ptr_impl::_M_ptr)
	(__uniq_ptr_impl::_M_deleter): Add noexcept.
2021-09-16 22:59:46 +01:00
Jonathan Wakely
89cf858571 libstdc++: Implement std::atomic<T*>::compare_exchange_weak
For some reason r170217 didn't add compare_exchange_weak to the
__atomic_base<T*> partial specialization, and so weak compare exchange
operations on pointers use compare_exchange_strong instead.

This adds __atomic_base<T*>::compare_exchange_weak and then uses it in
std::atomic<T*>::compare_exchange_weak.

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

libstdc++-v3/ChangeLog:

	* 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 18:22:33 +01:00
Jonathan Wakely
dba1ab2122 libstdc++: Remove "no stronger" assertion in compare exchange [PR102177]
P0418R2 removed some preconditions from std::atomic::compare_exchange_*
but we still enforce them via __glibcxx_assert. This removes those
assertions.

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

libstdc++-v3/ChangeLog:

	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 18:21:23 +01:00
Jonathan Wakely
763eb1f192 libstdc++: Add missing return for atomic timed wait [PR102074]
This adds a missing return statement to the non-futex wait-until
operation.

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

libstdc++-v3/ChangeLog:

	PR libstdc++/102074
	* include/bits/atomic_timed_wait.h (__timed_waiter_pool)
	[!_GLIBCXX_HAVE_PLATFORM_TIMED_WAIT]: Add missing return.
2021-08-31 17:36:12 +01:00
Jonathan Wakely
754fca77e8 libstdc++: Fix std::allocator<void> for versioned namespace
Removing the allocator<void> specialization for the versioned namespace
breaks _Extptr_allocator<void> because the allocator<void>
specialization was still declared in <bits/memoryfwd.h>, making it an
incomplete type.  It wrong to remove that specialization anyway, because
it is still needed pre-C++20.

This removes the #if ! _GLIBCXX_INLINE_VERSION check, so that
allocator<void> is still explicitly specialized for the versioned
namespace, consistent with the normal unversioned namespace mode.

To make _Extptr_allocator<void> usable as a ProtoAllocator, this change
adds a default constructor and converting constructor. That is
consistent with std::allocator<void> since C++20 (and harmless to do for
earlier standards).

I'm also explicitly specializing allocator_traits<allocator<void>> so
that it doesn't need to use allocator<void>::construct and destroy.
Doing that allows those members to be removed, further simplifying
allocator<void>.  That new explicit specialization can delete the
allocate, deallocate and max_size members, which are always ill-formed
for allocator<void>.

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

libstdc++-v3/ChangeLog:

	* 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 14:37:19 +01:00
Jonathan Wakely
dd3e5859fc libstdc++: Fix comment typo
Signed-off-by: Jonathan Wakely <jwakely@redhat.com>

libstdc++-v3/ChangeLog:

	* include/bits/stl_uninitialized.h: Fix typo in comment.
2021-08-28 11:52:22 +01:00
Jonathan Wakely
952095bb05 libstdc++: Name std::function template parameter
This avoids "<template-parameter-2-2>" being shown in the diagnostics
for ill-formed uses of std::function constructor:

In instantiation of 'std::function<_Res(_ArgTypes ...)>::function(_Functor&&)
[with _Functor = f(f()::_Z1fv.frame*)::<lambda()>;
<template-parameter-2-2> = void; _Res = void; _ArgTypes = {}]'

Instead we get:

In instantiation of 'std::function<_Res(_ArgTypes ...)>::function(_Functor&&)
[with _Functor = f(f()::_Z1fv.frame*)::<lambda()>;
_Constraints = void; _Res = void; _ArgTypes = {}]'

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

libstdc++-v3/ChangeLog:

	* include/bits/std_function.h (function::function(F&&)): Give
	name to defaulted template parameter, to improve diagnostics.
	Use markdown for more doxygen comments.
2021-08-28 11:52:22 +01:00
Jonathan Wakely
3a32a8ad7c libstdc:: Use markdown for Doxygen comments in std::function
Signed-off-by: Jonathan Wakely <jwakely@redhat.com>

libstdc++-v3/ChangeLog:

	* 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.
2021-08-27 00:12:54 +01:00
Jonathan Wakely
d38d26be33 libstdc++: Avoid a move in std::function construction (LWG 2447)
This makes the std::function constructor use perfect forwarding, to
avoid an unnecessary move-construction of the target. This means we need
to rewrite the _Function_base::_Base_manager::_M_init_functor function
to use a forwarding reference, and so can reuse it for the clone
operation.

Also simplify the SFINAE constraints on the constructor, by combining
the !is_same_v<remove_cvref_t<F>, function> constraint into the
_Callable trait.

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

libstdc++-v3/ChangeLog:

	* 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.
2021-08-27 00:12:54 +01:00
Jonathan Wakely
8cf428bfd3 libstdc++: Add static assertions for std::function requirements
Add static assertions to std::function, so that more user-friendly
diagnostics are given when trying to store a non-copyable target object.

These preconditions were added as "Mandates:" by LWG 2447, but I'm
committing them separately from implementing that, to allow just this
change to be backported more easily.

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

libstdc++-v3/ChangeLog:

	* include/bits/std_function.h (function::function(F)): Add
	static assertions to check constructibility requirements.
2021-08-27 00:12:54 +01:00
Jonathan Wakely
ead408529d libstdc++: Fix conditions for optimizing uninitialized algos [PR102064]
While laying some groundwork for constexpr std::vector, I noticed some
bugs in the std::uninitialized_xxx algorithms. The conditions being
checked for optimizing trivial cases were not quite right, as shown in
the examples in the PR.

This consolidates the checks into a single macro. The macro has
appropriate definitions for C++98 or for later standards, to avoid a #if
everywhere the checks are used. For C++11 and later the check makes a
call to a new function doing a static_assert to ensure we don't use
assignment in cases where construction would have been invalid.
Extracting that check to a separate function will be useful for
constexpr std::vector, as that can't use std::uninitialized_copy
directly because it isn't constexpr).

The consolidated checks mean that some slight variations in static
assert message are gone, as there is only one place that does the assert
now. That required adjusting some tests. As part of that the redundant
89164_c++17.cc test was merged into 89164.cc which is compiled as C++17
by default now, but can also use other -std options if the
C++17-specific error is made conditional with a target selector.

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

libstdc++-v3/ChangeLog:

	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 22:28:47 +01:00
Jonathan Wakely
30b300de8e libstdc++: Improve doxygen docs for smart pointers
Signed-off-by: Jonathan Wakely <jwakely@redhat.com>

libstdc++-v3/ChangeLog:

	* include/bits/shared_ptr.h: Add @since and @headerfile tags.
	* include/bits/unique_ptr.h: Add @headerfile tags.
2021-08-19 13:02:12 +01:00
Jonathan Wakely
c8a1cf1a7a libstdc++: Tweak whitespace
Signed-off-by: Jonathan Wakely <jwakely@redhat.com>

libstdc++-v3/ChangeLog:

	* include/bits/stl_tree.h: Tweak whitespace.
2021-08-19 13:02:11 +01:00
Jonathan Wakely
4fb471afc4 libstdc++: Improve doxygen documentation for std::unique_ptr
Add more detailed documentation for unique_ptr and related components.

The new alias templates for the _MakeUniq SFINAE helper make the
generated docs look better too.

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

libstdc++-v3/ChangeLog:

	* 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 15:13:08 +01:00
Jonathan Wakely
828176ba49 libstdc++: Improve doxygen comments in <bits/stl_function.h>
Add notes about deprecation and modern replacements. Fix bogus
"memory_adaptors" group name. Use markdown for formatting.

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

libstdc++-v3/ChangeLog:

	* include/bits/stl_function.h: Improve doxygen comments.
2021-08-18 15:07:16 +01:00
Jonathan Wakely
aba938d6c3 libstdc++: Enable doxygen processing for C++20 components
Improve grouping, add @since and @deprecated information.

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

libstdc++-v3/ChangeLog:

	* 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 15:02:31 +01:00
Jonathan Wakely
de44eee5d5 libstdc++: Minor optimization for min/max/minmax
The debug mode checks for a valid range are redundant when we have an
initializer_list argument, because we know it's a valid range already.
By making std::min(initialier_list<T>) call the internal __min_element
function directly we avoid a function call and skip those checks. The
same can be done for the overload taking a comparison function, and also
for the std::max and std::minmax overloads for initializer_list
arguments.

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

libstdc++-v3/ChangeLog:

	* 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 14:26:39 +01:00
Antony Polukhin
174f9257a7 libstdc++: Optimize std::seed_seq construction
When std::seed_seq is constructed from random access iterators we can
detect the internal vector size in O(1). Reserving memory for elements
in such cases may avoid multiple memory allocations.

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

libstdc++-v3/ChangeLog:

	* 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.

Co-authored-by: Jonathan Wakely <jwakely@redhat.com>
2021-08-17 16:53:19 +01:00
Jonathan Wakely
0808b0df9c libstdc++: Optimize std::function move constructor [PR101923]
PR 101923 points out that the unconditional swap in the std::function
move constructor makes it slower than copying an empty std::function.
The copy constructor has to check for the empty case before doing
anything, and that makes it very fast for the empty case.

Adding the same check to the move constructor avoids copying the
_Any_data POD when we don't need to. We can also inline the effects of
swap, by copying each member and then zeroing the pointer members.

This makes moving an empty object at least as fast as copying an empty
object.

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

libstdc++-v3/ChangeLog:

	PR libstdc++/101923
	* include/bits/std_function.h (function(function&&)): Check for
	non-empty parameter before doing any work.
2021-08-17 14:22:50 +01:00
Jonathan Wakely
3b3f2f7c26 libstdc++: Only define basic_string::contains for C++23
The new contains member of the COW string is defined for non-strict
gnu++20 mode as well as for C++23 modes. I think that was left in the
committed patch unintentionally. It is inconsistent with the SSO string,
and doesn't actually compile because it uses the
basic_string_view::contains member which only defined for C++23.

This makes it only defined for C++23.

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

libstdc++-v3/ChangeLog:

	* include/bits/cow_string.h (basic_string::contains): Do not
	define for -std=gnu++20.
2021-08-17 14:22:50 +01:00
Jonathan Wakely
c09cabb239 libstdc++: Rename __detail::__not_same_as helper
This is done to match an editorial change in the working draft, to
rename the exposition-only not-same-as helper to different-from.

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

libstdc++-v3/ChangeLog:

	* include/bits/ranges_util.h (__not_same_as): Rename to
	__different_from.
	* include/std/ranges (__not_same_as): Likewise.
2021-08-17 14:22:49 +01:00
Jonathan Wakely
f5a2d78072 libstdc++: Reduce use of debug containers in <regex>
The std::regex code uses std::map and std::vector, which means that when
_GLIBCXX_DEBUG is defined it uses the debug versions of those
containers. That no longer compiles, because I changed <regex> to
include <bits/stl_map.h> and <bits/stl_vector.h> instead of <map> and
<vector>, so the debug versions aren't defined, and std::map doesn't
compile. There is also a use of std::stack, which defaults to std::deque
which is the debug deque when _GLIBCXX_DEBUG is defined.

Using std::map, std::vector, and std::deque is probably a mistake, and
we should qualify them with _GLIBCXX_STD_C instead so that the debug
versions aren't used. We do not need the overhead of checking our own
uses of those containers, which should be correct anyway. The exception
is the vector base class of std::match_results, which exposes iterators
to users, so can benefit from debug mode checks for its iterators. For
other accesses to the vector elements, match_results already does its
own checks, so can access the _GLIBCXX_STD_C::vector base class
directly.

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

libstdc++-v3/ChangeLog:

	* 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 20:46:56 +01:00
Jonathan Wakely
c8b024fa4b libstdc++: Move [[nodiscard]] attributes again [PR101782]
Where I moved these nodiscard attributes to made them apply to the
function type, not to the function. This meant they no longer generated
the desired -Wunused-result warnings, and were ill-formed with Clang
(but only a pedwarn with GCC).

Clang also detected ill-formed attributes in <queue> which this fixes.

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

libstdc++-v3/ChangeLog:

	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 19:01:51 +01:00
Jonathan Wakely
7b1de3eb9e libstdc++: Move attributes that follow requires-clauses [PR101782]
As explained in the PR, the grammar in the Concepts TS means that a [
token following a requires-clause is parsed as part of the
logical-or-expression rather than the start of an attribute. That makes
the following ill-formed when using -fconcepts-ts:

  template<typename T> requires foo<T> [[nodiscard]] int f(T);

This change moves all attributes that follow a requires-clause to the
end of the function declarator.

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

libstdc++-v3/ChangeLog:

	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.
2021-08-05 15:16:58 +01:00
Jonathan Wakely
0d04fe4923 libstdc++: Add [[nodiscard]] to sequence containers
... and container adaptors.

This adds the [[nodiscard]] attribute to functions with no side-effects
for the sequence containers and their iterators, and the debug versions
of those containers, and the container adaptors,

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

libstdc++-v3/ChangeLog:

	* 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 12:54:29 +01:00
Jonathan Wakely
240b01b021 libstdc++: Add [[nodiscard]] to iterators and related utilities
This adds [[nodiscard]] throughout <iterator>, as proposed by P2377R0
(with some minor corrections).

The attribute is added for all modes from C++11 up, using
[[__nodiscard__]] or _GLIBCXX_NODISCARD where C++17 [[nodiscard]] can't
be used directly.

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

libstdc++-v3/ChangeLog:

	* 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.
2021-08-04 12:54:28 +01:00
Jonathan Wakely
a77a46d9ae libstdc++: Suppress redundant definitions of inline variables
In C++17 the out-of-class definitions for static constexpr variables are
redundant, because they are implicitly inline. This change avoids
"redundant redeclaration" warnings from -Wsystem-headers -Wdeprecated.

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

libstdc++-v3/ChangeLog:

	* 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 15:41:11 +01:00
Jonathan Wakely
7f2f4b8791 libstdc++: Deprecate std::random_shuffle for C++14
The std::random_shuffle algorithm was removed in C++14 (without
deprecation). This adds the deprecated attribute for C++14 and later, so
that users are warned they should not be using it in those dialects.

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

libstdc++-v3/ChangeLog:

	* 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 15:30:35 +01:00
Jonathan Wakely
e9f64fff64 libstdc++: Reduce header dependencies in <regex>
This reduces the size of <regex> a little. This is one of the largest
and slowest headers in the library.

By using <bits/stl_algobase.h> and <bits/stl_algo.h> instead of
<algorithm> we don't need to parse all the parallel algorithms and
std::ranges:: algorithms that are not needed by <regex>. Similarly, by
using <bits/stl_tree.h> and <bits/stl_map.h> instead of <map> we don't
need to parse the definition of std::multimap.

The _State_info type is not movable or copyable, so doesn't need to use
std::unique_ptr<bool[]> to manage a bitset, we can just delete it in the
destructor. It would use a lot less space if we used a bitset instead,
but that would be an ABI break. We could do it for the versioned
namespace, but this patch doesn't do so. For future reference, using
vector<bool> would work, but would increase sizeof(_State_info) by two
pointers, because it's three times as large as unique_ptr<bool[]>. We
can't use std::bitset because the length isn't constant. We want a
bitset with a non-constant but fixed length.

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

libstdc++-v3/ChangeLog:

	* 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 15:24:52 +01:00
Jonathan Wakely
a1a2654cdc libstdc++: Avoid using std::unique_ptr in <locale>
std::wstring_convert and std::wbuffer_convert types are not copyable or
movable, and store a plain pointer without a deleter. That means a much
simpler type that just uses delete in its destructor can be used instead
of std::unique_ptr.

That avoids including and parsing all of <bits/unique_ptr.h> in every
header that includes <locale>. It also avoids instantiating
unique_ptr<C> and std::tuple<C*, default_delete<C>> when the conversion
utilities are used.

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

libstdc++-v3/ChangeLog:

	* 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.
2021-08-03 15:06:56 +01:00
Patrick Palka
14d8a5ae47 libstdc++: Add missing std::move to ranges::copy/move/reverse_copy [PR101599]
In passing, this also renames the template parameter _O2 to _Out2 in
ranges::partition_copy and uglifies two of its function parameters,
out_true and out_false.

	PR libstdc++/101599

libstdc++-v3/ChangeLog:

	* 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 15:30:15 -04:00
Jonathan Wakely
7ffba77d01 libstdc++: Adjust whitespace in <bits/cow_string.h>
libstdc++-v3/ChangeLog:

	* include/bits/cow_string.h: Consistently use tab for
	indentation.
2021-07-27 12:13:42 +01:00
Jonathan Wakely
7b527614dd libstdc++: Move COW string definitions to separate header
This moves the definitions of the COW string to a separate file, so that
they don't need to be preprocessed for the common case. We could also
move the SSO string definitions to a new file, so that they don't need
to be preprocessed for the old ABI case, but that would require more
shovel work because there are some parts of <bits/basic_string.h> and
<bits/basic_string.tcc> that are common to both definitions.

libstdc++-v3/ChangeLog:

	* 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 12:04:18 +01:00
Jonathan Wakely
16158c9649 libstdc++: Remove unnecessary uses of <utility>
The <algorithm> header includes <utility>, with a comment referring to
UK-300, a National Body comment on the C++11 draft. That comment
proposed to move std::swap to <utility> and then require <algorithm> to
include <utility>. The comment was rejected, so we do not need to
implement the suggestion. For backwards compatibility with C++03 we do
want <algorithm> to define std::swap, but it does so anyway via
<bits/move.h>. We don't need the whole of <utility> to do that.

A few other headers that need std::swap can include <bits/move.h> to
get it, instead of <utility>.

There are several headers that include <utility> to get std::pair, but
they can use <bits/stl_pair.h> to get it without also including the
rel_ops namespace and other contents of <utility>.

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

libstdc++-v3/ChangeLog:

	* 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 12:04:18 +01:00
Jonathan Wakely
261d5a4a45 libstdc++: Reduce header dependencies on <array> and <utility>
This refactoring reduces the memory usage and compilation time to parse
a number of headers that depend on std::pair, std::tuple or std::array.
Previously the headers for these class templates were all intertwined,
due to the common dependency on std::tuple_size, std::tuple_element and
their std::get overloads. This decouples the headers by moving some
parts of <utility> into a new <bits/utility.h> header. This means that
<array> and <tuple> no longer need to include the whole of <utility>,
and <tuple> no longer needs to include <array>.

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

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

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

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

libstdc++-v3/ChangeLog:

	* include/Makefile.am: Add bits/utility.h header.
	* include/Makefile.in: Regenerate.
	* include/bits/utility.h: New file.
	* include/std/utility (tuple_size, tuple_element): Move
	to new header.
	* include/std/type_traits (__is_tuple_like_impl<tuple<T...>>):
	Move to <tuple>.
	(_Index_tuple, _Build_index_tuple, integer_sequence): Likewise.
	(in_place_t, in_place_index_t, in_place_type_t): Likewise.
	* include/bits/ranges_util.h: Include new header instead of
	<utility>.
	* include/bits/stl_pair.h (tuple_size, tuple_element): Move
	partial specializations for std::pair here.
	(get): Move overloads for std::pair here.
	* include/std/any: Include new header instead of <utility>.
	* include/std/array: Likewise.
	* include/std/memory_resource: Likewise.
	* include/std/optional: Likewise.
	* include/std/variant: Likewise.
	* include/std/tuple: Likewise.
	(__is_tuple_like_impl<tuple<T...>>): Move here.
	(get) Declare overloads for std::array.
	* include/std/version (__cpp_lib_tuples_by_type): Change type
	to long.
	* testsuite/20_util/optional/84601.cc: Include <utility>.
	* testsuite/20_util/specialized_algorithms/uninitialized_fill/constrained.cc:
	Likewise.
	* testsuite/23_containers/array/tuple_interface/get_neg.cc:
	Adjust dg-error line numbers.
	* testsuite/std/ranges/access/cbegin.cc: Include <utility>.
	* testsuite/std/ranges/access/cend.cc: Likewise.
	* testsuite/std/ranges/access/end.cc: Likewise.
	* testsuite/std/ranges/single_view.cc: Likewise.
2021-07-27 12:04:18 +01:00