https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108951
--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> --- std::allocator<T> can be a program-defined specialization, which might obtain memory without using operator new, so changing __valarray_get_storage to use std::allocator would be an ABI break. Using std::__new_allocator would be OK though, because users shouldn't be specializing that. Except that we don't have __n in __valarray_release_memory so we can't use an allocator.
