This looks to have been wrong since r0-125454-gea89b2482f97aa which introduced the predefined_ops.h. Since that change, the binary predicate passed to std::__unique_copy is _Iter_comp_iter, which takes arguments of the iterator type, not the iterator's value type.
This removes the checks from the __unique_copy overloads and moves them into the second overload of std::unique_copy, where we have the original binary predicate, not the adapted one from predefined_ops.h. The third __unique_copy overload currently checks that the predicate is callable with the input range value type and the output range value type. This change alters that, so that we only ever check that the predicate can be called with two arguments of the same type. That is intentional, because calling the predicate with different types is a bug that will be fixed in a later commit (see PR libstdc++/120386). libstdc++-v3/ChangeLog: PR libstdc++/120384 * include/bits/stl_algo.h (__unique_copy): Remove all _BinaryPredicateConcept concept checks. (unique_copy): Check _BinaryPredicateConcept in overload that takes a predicate. * testsuite/25_algorithms/unique_copy/120384.cc: New test. --- Tested x86_64-linux. libstdc++-v3/include/bits/stl_algo.h | 17 +++-------------- .../25_algorithms/unique_copy/120384.cc | 12 ++++++++++++ 2 files changed, 15 insertions(+), 14 deletions(-) create mode 100644 libstdc++-v3/testsuite/25_algorithms/unique_copy/120384.cc diff --git a/libstdc++-v3/include/bits/stl_algo.h b/libstdc++-v3/include/bits/stl_algo.h index 71ead103d2bf..f5361aeab7e2 100644 --- a/libstdc++-v3/include/bits/stl_algo.h +++ b/libstdc++-v3/include/bits/stl_algo.h @@ -932,11 +932,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION _OutputIterator __result, _BinaryPredicate __binary_pred, forward_iterator_tag, output_iterator_tag) { - // concept requirements -- iterators already checked - __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate, - typename iterator_traits<_ForwardIterator>::value_type, - typename iterator_traits<_ForwardIterator>::value_type>) - _ForwardIterator __next = __first; *__result = *__first; while (++__next != __last) @@ -962,11 +957,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION _OutputIterator __result, _BinaryPredicate __binary_pred, input_iterator_tag, output_iterator_tag) { - // concept requirements -- iterators already checked - __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate, - typename iterator_traits<_InputIterator>::value_type, - typename iterator_traits<_InputIterator>::value_type>) - typename iterator_traits<_InputIterator>::value_type __value = *__first; __decltype(__gnu_cxx::__ops::__iter_comp_val(__binary_pred)) __rebound_pred @@ -995,10 +985,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION _ForwardIterator __result, _BinaryPredicate __binary_pred, input_iterator_tag, forward_iterator_tag) { - // concept requirements -- iterators already checked - __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate, - typename iterator_traits<_ForwardIterator>::value_type, - typename iterator_traits<_InputIterator>::value_type>) *__result = *__first; while (++__first != __last) if (!__binary_pred(__result, __first)) @@ -4505,6 +4491,9 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator, typename iterator_traits<_InputIterator>::value_type>) __glibcxx_requires_valid_range(__first, __last); + __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate, + typename iterator_traits<_InputIterator>::value_type, + typename iterator_traits<_InputIterator>::value_type>) if (__first == __last) return __result; diff --git a/libstdc++-v3/testsuite/25_algorithms/unique_copy/120384.cc b/libstdc++-v3/testsuite/25_algorithms/unique_copy/120384.cc new file mode 100644 index 000000000000..27cd3375acae --- /dev/null +++ b/libstdc++-v3/testsuite/25_algorithms/unique_copy/120384.cc @@ -0,0 +1,12 @@ +// { dg-options "-D_GLIBCXX_CONCEPT_CHECKS" } +// { dg-do compile } + +// PR 120384 _BinaryPredicateConcept checks in std::unique_copy are wrong + +#include <algorithm> + +void +test_pr120384(const int* first, const int* last, int* out) +{ + std::unique_copy(first, last, out); +} -- 2.49.0