https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100795
--- Comment #15 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Patrick Palka <ppa...@gcc.gnu.org>: https://gcc.gnu.org/g:a148b0377805376e33f36bed0e48a401a6dd82c6 commit r16-1740-ga148b0377805376e33f36bed0e48a401a6dd82c6 Author: Patrick Palka <ppa...@redhat.com> Date: Fri Jun 27 13:52:56 2025 -0400 libstdc++: Directly implement ranges::heap algos [PR100795] ranges::push_heap, ranges::pop_heap, ranges::make_heap and ranges::sort_heap are currently defined in terms of the corresponding STL-style algorithms, but this is incorrect because the STL-style algorithms rely on the legacy iterator system, and so misbehave when passed a narrowly C++20 random access iterator. The other ranges heap algos, ranges::is_heap and ranges::is_heap_until, are implemented directly already and have no known issues. This patch reimplements these ranges:: algos directly instead, based closely on the legacy stl_heap.h implementation, with the following changes for compatibility with the C++20 iterator system: - handle non-common ranges by computing the corresponding end iterator - use ranges::iter_move instead of std::move(*iter) - use iter_value_t / iter_difference_t instead of iterator_traits Besides these changes, the implementation of these algorithms is intended to mirror the stl_heap.h implementations, for ease of maintenance and review. Note that we don't explicitly pass the projection function throughout, instead we just create and pass a composite predicate via __make_comp_proj. PR libstdc++/100795 libstdc++-v3/ChangeLog: * include/bits/ranges_algo.h (__detail::__push_heap): New, based on the stl_heap.h implementation. (__push_heap_fn::operator()): Reimplement in terms of the above. (__detail::__adjust_heap): New, based on the stl_heap.h implementation. (__deatil::__pop_heap): Likewise. (__pop_heap_fn::operator()): Reimplement in terms of the above. (__make_heap_fn::operator()): Likewise. (__sort_heap_fn::operator()): Likewise. * testsuite/25_algorithms/heap/constrained.cc (test03): New test. Reviewed-by: Tomasz KamiÅski <tkami...@redhat.com> Reviewed-by: Jonathan Wakely <jwak...@redhat.com>
