[Bug libstdc++/100249] missing forwarding std::__invoke result in ranges::is_permutation and ranges::clamp

[ppalka at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100249

--- Comment #4 from Patrick Palka <ppalka at gcc dot gnu.org> ---
(In reply to 康桓瑋 from comment #0)
> when the type of __proj_val is an rvalue reference, we need to convert it to
> rvalue for the next std::__invoke call: https://godbolt.org/z/1G7aqxs3c.

So it seems the projection application limit of 3 makes it impossible for
ranges::clamp to perfectly support the case where the projection returns an
rvalue reference.