My recent changes to std::exception_ptr moved some members to be inline
in the header but didn't replace the variable names with reserved names.
The "tmp" variable must be fixed. The "other" parameter is actually a
reserved name because of std::allocator<T>::rebind<U>::other but should
be fixed anyway.
There are also some bad uses of "ForwardIterator" in <ranges>.
There's also a "il" parameter in a std::seed_seq constructor in <random>
which is only reserved since C++14.
libstdc++-v3/ChangeLog:
* include/bits/random.h (seed_seq(initializer_list<T>)): Rename
parameter to use reserved name.
* include/bits/ranges_algo.h (shift_left, shift_right): Rename
template parameters to use reserved name.
* libsupc++/exception_ptr.h (exception_ptr): Likewise for
parameters and local variables.
* testsuite/17_intro/names.cc: Check "il". Do not check "d" and
"y" in C++20 mode.
This introduces two new headers:
<bits/ranges_base.h> defines the minimal components needed
for using C++20 ranges (customization point objects such as
std::ranges::begin, concepts such as std::ranges::range, etc.)
<bits/ranges_util.h> includes <bits/ranges_base.h> and additionally
defines subrange, which is needed by <bits/ranges_algo.h>.
Most of the content of <bits/ranges_base.h> was previously defined in
<bits/range_access.h>, but a few pieces were only defined in <ranges>.
This meant the entire <ranges> header was needed in <algorithm> and
<memory>, even though they don't use all the range adaptors.
By moving the ranges components out of <bits/range_access.h> that file
is left defining just the contents of [iterator.range] i.e. std::begin,
std::end, std::size etc. and not C++20 ranges components.
For consistency with other C++20 ranges headers, <bits/range_cmp.h> is
renamed to <bits/ranges_cmp.h>.
libstdc++-v3/ChangeLog:
* include/Makefile.am: Add new headers and adjust for renamed
header.
* include/Makefile.in: Regenerate.
* include/bits/iterator_concepts.h: Adjust for renamed header.
* include/bits/range_access.h (ranges::*): Move to new
<bits/ranges_base.h> header.
* include/bits/ranges_algobase.h: Include new <bits/ranges_base.h>
header instead of <ranges>.
* include/bits/ranges_algo.h: Include new <bits/ranges_util.h>
header.
* include/bits/range_cmp.h: Moved to...
* include/bits/ranges_cmp.h: ...here.
* include/bits/ranges_base.h: New header.
* include/bits/ranges_util.h: New header.
* include/experimental/string_view: Include new
<bits/ranges_base.h> header.
* include/std/functional: Adjust for renamed header.
* include/std/ranges (ranges::view_base, ranges::enable_view)
(ranges::dangling, ranges::borrowed_iterator_t): Move to new
<bits/ranges_base.h> header.
(ranges::view_interface, ranges::subrange)
(ranges::borrowed_subrange_t): Move to new <bits/ranges_util.h>
header.
* include/std/span: Include new <bits/ranges_base.h> header.
* include/std/string_view: Likewise.
* testsuite/24_iterators/back_insert_iterator/pr93884.cc: Add
missing <ranges> header.
* testsuite/24_iterators/front_insert_iterator/pr93884.cc:
Likewise.
The spaceship operator for std::array uses memcmp when the
__is_byte<value_type> trait is true, but memcmp isn't usable in
constexpr contexts. Also, memcmp should only be used for unsigned byte
types, because it gives the wrong answer for signed chars with negative
values.
We can simply check std::is_constant_evaluated() so that we don't use
memcmp during constant evaluation.
To fix the problem of using memcmp for inappropriate types, this patch
adds new __is_memcmp_ordered and __is_memcmp_ordered_with traits. These
say whether using memcmp will give the right answer for ordering
operations such as lexicographical_compare and three-way comparisons.
The new traits can be used in several places, and can also be used to
implement my suggestion in PR 93059 comment 37 to use memcmp for
unsigned integers larger than one byte on big endian targets.
libstdc++-v3/ChangeLog:
PR libstdc++/96851
* include/bits/cpp_type_traits.h (__is_memcmp_ordered):
New trait that says if memcmp can be used for ordering.
(__is_memcmp_ordered_with): Likewise, for two types.
* include/bits/deque.tcc (__lex_cmp_dit): Use new traits
instead of __is_byte and __numeric_traits.
(__lexicographical_compare_aux1): Likewise.
* include/bits/ranges_algo.h (__lexicographical_compare_fn):
Likewise.
* include/bits/stl_algobase.h (__lexicographical_compare_aux1)
(__is_byte_iter): Likewise.
* include/std/array (operator<=>): Likewise. Only use memcmp
when std::is_constant_evaluated() is false.
* testsuite/23_containers/array/comparison_operators/96851.cc:
New test.
* testsuite/23_containers/array/tuple_interface/get_neg.cc:
Adjust dg-error line numbers.
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.
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.
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.
Several algorithms check the is_trivially_copyable trait to decide
whether to dispatch to memmove or memcmp as an optimization. Since
r271435 (CWG DR 2094) the trait is true for volatile-qualified scalars,
but we can't use memmove or memcmp when the type is volatile. We need to
also check for volatile types.
This is complicated by the fact that in C++20 (but not earlier standards)
iterator_traits<volatile T*>::value_type is T, so we can't just check
whether the value_type is volatile.
The solution in this patch is to introduce new traits __memcpyable and
__memcmpable which combine into a single trait the checks for pointers,
the value types being the same, and the type being trivially copyable
but not volatile-qualified.
PR libstdc++/94013
* include/bits/cpp_type_traits.h (__memcpyable, __memcmpable): New
traits to control when to use memmove and memcmp optimizations.
(__is_nonvolatile_trivially_copyable): New helper trait.
* include/bits/ranges_algo.h (__lexicographical_compare_fn): Do not
use memcmp optimization with volatile data.
* include/bits/ranges_algobase.h (__equal_fn): Use __memcmpable.
(__copy_or_move, __copy_or_move_backward): Use __memcpyable.
* include/bits/stl_algobase.h (__copy_move_a2): Use __memcpyable.
(__copy_move_backward_a2): Likewise.
(__equal_aux1): Use __memcmpable.
(__lexicographical_compare_aux): Do not use memcmp optimization with
volatile data.
* testsuite/25_algorithms/copy/94013.cc: New test.
* testsuite/25_algorithms/copy_backward/94013.cc: New test.
* testsuite/25_algorithms/equal/94013.cc: New test.
* testsuite/25_algorithms/fill/94013.cc: New test.
* testsuite/25_algorithms/lexicographical_compare/94013.cc: New test.
* testsuite/25_algorithms/move/94013.cc: New test.
* testsuite/25_algorithms/move_backward/94013.cc: New test.
We were enabling the memcmp optimization in ranges::lexicographical_compare for
signed integral types and for integral types wider than a byte. But memcmp
gives the wrong answer for arrays of such types. This patch fixes this issue by
refining the condition that enables the memcmp optimization. It's now
consistent with the corresponding condition used in
std::lexicographical_compare.
libstdc++-v3/ChangeLog:
PR libstdc++/93972
* include/bits/ranges_algo.h (__lexicographical_compare_fn::operator()):
Fix condition for when to use memcmp, making it consistent with the
corresponding condition used in std::lexicographical_compare.
* testsuite/25_algorithms/lexicographical_compare/93972.cc: New test.
* include/bits/ranges_algo.h (__lexicographical_compare_fn): Declare
variables in smaller scope and avoid calling ranges::distance when we
know they are pointers. Remove statically-unreachable use of
__builtin_unreachable().
* include/bits/stl_algobase.h (__lexicographical_compare::__lc):
Define inline.
This patch adds std::shift_left and std::shift_right as per P0769R2. Alhough
these are STL-style algos, this patch places them in <bits/ranges_algo.h>
because they make use of some functions in the ranges namespace that are more
easily reachable from <bits/ranges_algo.h> than from <bits/stl_algo.h>, namely
ranges::next. In order to place these algos in <bits/stl_algo.h>, we would need
to include <bits/range_access.h> from <bits/stl_algo.h> which would undesirably
increase the size of <bits/stl_algo.h>.
libstdc++-v3/ChangeLog:
P0769R2 Add shift to <algorithm>
* include/bits/ranges_algo.h (shift_left, shift_right): New.
* testsuite/25_algorithms/shift_left/1.cc: New test.
* testsuite/25_algorithms/shift_right/1.cc: New test.
Some of these casts were added by me the other day, but some were
already present. I think they are all redundant following the
introduction of the boolean-testable concept in P1964R2.
* include/bits/ranges_algo.h (__find_fn, __find_first_of_fn)
(__adjacent_find_fn, __remove_if_fn, __remove_copy_if_fn)
(__unique_fn, __unique_copy_fn): Remove redundant conversions to bool.
libstdc++-v3/ChangeLog:
P2106R0 Alternative wording for GB315 and GB316
* include/bits/ranges_algo.h (in_fun_result): New.
(for_each_result, for_each_n_result): Change into an alias of
in_fun_result.
(in_in_result): New.
(mismatch_result): Change into an alias of in_in_result.
(copy_if_result): Change into an alias of in_out_result.
(swap_ranges_result): Change into an alias of in_in_result.
(unary_transform_result): Change into an alias of in_out_result.
(in_in_out_result): New.
(binary_transform_result): Change into an alias of in_in_out_result.
(replace_copy_result, replace_copy_if_result, remove_copy_if_result,
remove_copy_result, unique_copy_result, reverse_copy_result,
rotate_copy_result, partial_sort_copy_result): Change into an alias of
in_out_result.
(in_out_out_result): New.
(partition_copy_result, merge_result): Change into an alias of
in_out_out_result.
(set_union_result, set_intersection_result): Change into an alias of
in_in_out_result.
(set_difference_result): Change into an alias of in_out_result.
(set_symmetric_difference): Change into an alias of in_in_out_result.
(min_max_result): New.
(minmax_result, minmax_element_result): Change into an alias of
min_max_result.
(in_found_result): New.
(next_permutation_result, prev_permutation_result): Change into an alias
of in_found_result.
(__next_permutation_fn::operator(), __prev_permutation_fn::operator()):
Adjust following changes to next_permutation_result and
prev_permutation_result.
* include/bits/ranges_algobase.h (in_out_result): New.
(copy_result, move_result, move_backward_result, copy_backward_result,
copy_n_result): Change into an alias of in_out_result.
* include/bits/ranges_uninitialized.h (uninitialized_copy_result,
uninitialized_copy_n_result, uninitialized_move_result,
uninitialized_move_n_result): Likewise.
* testsuite/25_algorithms/next_permutation/constrained.cc: Adjust uses of
structured bindings.
* testsuite/25_algorithms/prev_permutation/constrained.cc: Likewise.
This adds rangified overloads for for_each_n, sample and clamp as per P1243R4.
libstdc++-v3/ChangeLog:
P1243R4 Rangify new algorithms
* include/bits/ranges_algo.h (for_each_n_result, __for_each_n_fn,
for_each_n, __sample_fn, sample, __clamp_fn, clamp): New.
* testsuite/25_algorithms/clamp/constrained.cc: New test.
* testsuite/25_algorithms/for_each/constrained.cc: Augment test.
* testsuite/25_algorithms/sample/constrained.cc: New test.
This removes the complicated std::boolean concept, as agreed in Prague.
* include/bits/ranges_algo.h (__find_fn, __find_first_of_fn)
(__adjacent_find_fn): Cast result of predicate to bool.
* include/std/concepts (__boolean): Remove.
(__detail::__boolean_testable_impl, __detail::__boolean_testable): Add
new helper concepts.
(__detail::__weakly_eq_cmp_with, totally_ordered, totally_ordered_with)
(predicate): Use __boolean_testable instead of boolean.
* libsupc++/compare (__detail::__partially_ordered, _Synth3way):
Likewise.
In C++20 <memory> depends on <bits/ranges_unitialized.h> which
depends on <bits/random.h> just for a single concept. Including
<bits/random.h> also requires including <cmath>, which is huge due to
the C++17 special functions.
This change moves the concept to the <bits/uniform_int_dist.h> internal
header that exists so that <bits/stl_algobase.h> doesn't need to include
<bits/random.h>.
PR libstdc++/92546 (partial)
* include/bits/random.h (uniform_random_bit_generator): Move definition
to <bits/uniform_int_dist.h>.
* include/bits/ranges_algo.h: Include <bits/uniform_int_dist.h> instead
of <bits/random.h>.
* include/bits/ranges_algobase.h: Do not include <cmath>.
* include/bits/uniform_int_dist.h (uniform_random_bit_generator):
Move here.
* include/std/ranges: Do not include <limits>.
* testsuite/26_numerics/random/pr60037-neg.cc: Adjust dg-error lineno.
This avoids instantiating dead code when the true branch of the constexpr if is
taken.
libstdc++-v3/ChangeLog:
* include/bits/ranges_algo.h (__lexicographical_compare_fn::operator()):
Move code after an early exit constexpr if to under an else branch.
* include/bits/ranges_algobase.h (__equal_fn::operator()): Likewise.
These subroutines have only a single call site, so it might be best and simplest
to eliminate them before we convert the algos into function objects.
libstdc++-v3/ChangeLog:
* include/bits/ranges_algo.h (ranges::__find_end): Fold into ...
(ranges::find_end): ... here.
(ranges::__lexicographical_compare): Fold into ...
(ranges::lexicographical_compare): ... here.
* include/bits/ranges_algobase.h (ranges::__equal): Fold into ...
(ranges::equal): ... here.
This roughly mirrors the existing split between <bits/stl_algo.h> and
<bits/stl_algobase.h>. The ranges [specialized.algorithms] will use this new
header to avoid including all of of <bits/ranges_algo.h>.
libstdc++-v3/ChangeLog:
* include/Makefile.am: Add bits/ranges_algobase.h
* include/Makefile.in: Regenerate.
* bits/ranges_algo.h: Include <bits/ranges_algobase.h> and refactor
existing #includes.
(__detail::__is_normal_iterator, __detail::is_reverse_iterator,
__detail::__is_move_iterator, copy_result, move_result,
__equal, equal, copy_result, move_result, move_backward_result,
copy_backward_result, __copy_or_move_backward, __copy_or_move, copy,
move, copy_backward, move_backward, copy_n_result, copy_n, fill_n,
fill): Split out into ...
* bits/range_algobase.h: ... this new header.
* include/bits/iterator_concepts.h (iter_difference_t, iter_value_t):
Use remove_cvref_t.
(readable_traits): Rename to indirectly_readable_traits.
(readable): Rename to indirectly_readable.
(writable): Rename to indirectly_writable.
(__detail::__iter_exchange_move): Do not use remove_reference_t.
(indirectly_swappable): Adjust requires expression parameter types.
expression.
* include/bits/ranges_algo.h (ranges::transform, ranges::replace)
(ranges::replace_if, ranges::generate_n, ranges::generate)
(ranges::remove): Use new name for writable.
* include/bits/stl_iterator.h (__detail::__common_iter_has_arrow):
Use new name for readable.
* include/ext/pointer.h (readable_traits<_Pointer_adapter<P>>): Use
new name for readable_traits.
* testsuite/24_iterators/associated_types/readable.traits.cc: Likewise.
* testsuite/24_iterators/indirect_callable/projected.cc: Adjust for
new definition of indirectly_readable.
This patch implements the C++20 ranges overloads for the algorithms in
[algorithms]. Most of the algorithms were reimplemented, with each of their
implementations very closely following the existing implementation in
bits/stl_algo.h and bits/stl_algobase.h. The reason for reimplementing most of
the algorithms instead of forwarding to their STL-style overload is because
forwarding cannot be conformantly and efficiently performed for algorithms that
operate on non-random-access iterators. But algorithms that operate on random
access iterators can safely and efficiently be forwarded to the STL-style
implementation, and this patch does so for push_heap, pop_heap, make_heap,
sort_heap, sort, stable_sort, nth_element, inplace_merge and stable_partition.
What's missing from this patch is debug-iterator and container specializations
that are present for some of the STL-style algorithms that need to be ported
over to the ranges algos. I marked them missing at TODO comments. There are
also some other minor outstanding TODOs.
The code that could use the most thorough review is ranges::__copy_or_move,
ranges::__copy_or_move_backward, ranges::__equal and
ranges::__lexicographical_compare. In the tests, I tried to test the interface
of each new overload, as well as the correctness of the new implementation.
libstdc++-v3/ChangeLog:
Implement C++20 constrained algorithms
* include/Makefile.am: Add new header.
* include/Makefile.in: Regenerate.
* include/std/algorithm: Include <bits/ranges_algo.h>.
* include/bits/ranges_algo.h: New file.
* testsuite/25_algorithms/adjacent_find/constrained.cc: New test.
* testsuite/25_algorithms/all_of/constrained.cc: New test.
* testsuite/25_algorithms/any_of/constrained.cc: New test.
* testsuite/25_algorithms/binary_search/constrained.cc: New test.
* testsuite/25_algorithms/copy/constrained.cc: New test.
* testsuite/25_algorithms/copy_backward/constrained.cc: New test.
* testsuite/25_algorithms/copy_if/constrained.cc: New test.
* testsuite/25_algorithms/copy_n/constrained.cc: New test.
* testsuite/25_algorithms/count/constrained.cc: New test.
* testsuite/25_algorithms/count_if/constrained.cc: New test.
* testsuite/25_algorithms/equal/constrained.cc: New test.
* testsuite/25_algorithms/equal_range/constrained.cc: New test.
* testsuite/25_algorithms/fill/constrained.cc: New test.
* testsuite/25_algorithms/fill_n/constrained.cc: New test.
* testsuite/25_algorithms/find/constrained.cc: New test.
* testsuite/25_algorithms/find_end/constrained.cc: New test.
* testsuite/25_algorithms/find_first_of/constrained.cc: New test.
* testsuite/25_algorithms/find_if/constrained.cc: New test.
* testsuite/25_algorithms/find_if_not/constrained.cc: New test.
* testsuite/25_algorithms/for_each/constrained.cc: New test.
* testsuite/25_algorithms/generate/constrained.cc: New test.
* testsuite/25_algorithms/generate_n/constrained.cc: New test.
* testsuite/25_algorithms/heap/constrained.cc: New test.
* testsuite/25_algorithms/includes/constrained.cc: New test.
* testsuite/25_algorithms/inplace_merge/constrained.cc: New test.
* testsuite/25_algorithms/is_partitioned/constrained.cc: New test.
* testsuite/25_algorithms/is_permutation/constrained.cc: New test.
* testsuite/25_algorithms/is_sorted/constrained.cc: New test.
* testsuite/25_algorithms/is_sorted_until/constrained.cc: New test.
* testsuite/25_algorithms/lexicographical_compare/constrained.cc: New
test.
* testsuite/25_algorithms/lower_bound/constrained.cc: New test.
* testsuite/25_algorithms/max/constrained.cc: New test.
* testsuite/25_algorithms/max_element/constrained.cc: New test.
* testsuite/25_algorithms/merge/constrained.cc: New test.
* testsuite/25_algorithms/min/constrained.cc: New test.
* testsuite/25_algorithms/min_element/constrained.cc: New test.
* testsuite/25_algorithms/minmax/constrained.cc: New test.
* testsuite/25_algorithms/minmax_element/constrained.cc: New test.
* testsuite/25_algorithms/mismatch/constrained.cc: New test.
* testsuite/25_algorithms/move/constrained.cc: New test.
* testsuite/25_algorithms/move_backward/constrained.cc: New test.
* testsuite/25_algorithms/next_permutation/constrained.cc: New test.
* testsuite/25_algorithms/none_of/constrained.cc: New test.
* testsuite/25_algorithms/nth_element/constrained.cc: New test.
* testsuite/25_algorithms/partial_sort/constrained.cc: New test.
* testsuite/25_algorithms/partial_sort_copy/constrained.cc: New test.
* testsuite/25_algorithms/partition/constrained.cc: New test.
* testsuite/25_algorithms/partition_copy/constrained.cc: New test.
* testsuite/25_algorithms/partition_point/constrained.cc: New test.
* testsuite/25_algorithms/prev_permutation/constrained.cc: New test.
* testsuite/25_algorithms/remove/constrained.cc: New test.
* testsuite/25_algorithms/remove_copy/constrained.cc: New test.
* testsuite/25_algorithms/remove_copy_if/constrained.cc: New test.
* testsuite/25_algorithms/remove_if/constrained.cc: New test.
* testsuite/25_algorithms/replace/constrained.cc: New test.
* testsuite/25_algorithms/replace_copy/constrained.cc: New test.
* testsuite/25_algorithms/replace_copy_if/constrained.cc: New test.
* testsuite/25_algorithms/replace_if/constrained.cc: New test.
* testsuite/25_algorithms/reverse/constrained.cc: New test.
* testsuite/25_algorithms/reverse_copy/constrained.cc: New test.
* testsuite/25_algorithms/rotate/constrained.cc: New test.
* testsuite/25_algorithms/rotate_copy/constrained.cc: New test.
* testsuite/25_algorithms/search/constrained.cc: New test.
* testsuite/25_algorithms/search_n/constrained.cc: New test.
* testsuite/25_algorithms/set_difference/constrained.cc: New test.
* testsuite/25_algorithms/set_intersection/constrained.cc: New test.
* testsuite/25_algorithms/set_symmetric_difference/constrained.cc: New
test.
* testsuite/25_algorithms/set_union/constrained.cc: New test.
* testsuite/25_algorithms/shuffle/constrained.cc: New test.
* testsuite/25_algorithms/sort/constrained.cc: New test.
* testsuite/25_algorithms/stable_partition/constrained.cc: New test.
* testsuite/25_algorithms/stable_sort/constrained.cc: New test.
* testsuite/25_algorithms/swap_ranges/constrained.cc: New test.
* testsuite/25_algorithms/transform/constrained.cc: New test.
* testsuite/25_algorithms/unique/constrained.cc: New test.
* testsuite/25_algorithms/unique_copy/constrained.cc: New test.
* testsuite/25_algorithms/upper_bound/constrained.cc: New test.
