We already implement short-circuiting for random access iterators, but
we also need to do so for ranges::equal and ranges::is_permutation when
given sized ranges that are not random access ranges (e.g. std::list).
libstdc++-v3/ChangeLog:
* include/bits/ranges_algo.h (__is_permutation_fn::operator()):
Short-circuit for sized ranges with different sizes, as per LWG
3560.
* include/bits/ranges_algobase.h (__equal_fn::operator()):
Likewise.
* include/bits/stl_algo.h (__is_permutation): Use if-constexpr
for random access iterator branches.
* include/bits/stl_algobase.h (__equal4): Likewise.
* testsuite/25_algorithms/equal/lwg3560.cc: New test.
* testsuite/25_algorithms/is_permutation/lwg3560.cc: New test.
Reviewed-by: Patrick Palka <ppalka@redhat.com>
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