commit 925a744efec5a630eb9bf49e755c554a884fda99
author Patrick Palka <ppalka@redhat.com> Thu Mar 13 09:15:21 2025 -0400
committer Patrick Palka <ppalka@redhat.com> Tue Mar 25 10:43:41 2025 -0400
tree eda432e3a053387b83e2ba719c61238fd2ef4886
parent f078a613bf85eff138c2567b599779dee6ae4b22

libstdc++: Fix ref_view branch of views::as_const [PR119135]

Unlike for span<X> and empty_view<X>, the range_reference_t of
ref_view<X> doesn't correspond to X.  This patch fixes the ref_view
branch of views::as_const to correctly query its underlying range
type X.

	PR libstdc++/119135

libstdc++-v3/ChangeLog:

	* include/std/ranges: Include <utility>.
	(views::__detail::__is_ref_view): Replace with ...
	(views::__detail::__is_constable_ref_view): ... this.
	(views::_AsConst::operator()): Replace bogus use of element_type
	in the ref_view branch.
	* testsuite/std/ranges/adaptors/as_const/1.cc (test03): Extend
	test.

Reviewed-by: Tomasz Kamiński <tkaminsk@redhat.com>
Reviewed-by: Jonathan Wakely <jwakely@redhat.com>
(cherry picked from commit 50359c0a44381edb6dbd9359ef2ebdadbcc3ed42)