[Bug ipa/110057] Missed devirtualization opportunities

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110057

--- Comment #13 from Jonathan Wakely <redi at gcc dot gnu.org> ---
That would only be valid for std::allocator and other allocators where
std::allocator_traits<A>::destroy uses std::destroy_at.

As it happens, I've just refactored std::allocator_traits today, which makes it
possible to test for exactly that condition.