
We were not declaring `__uses_allocator_construction_args` helper functions, leading to several valid uses failing to compile. This patch solves the problem by moving these helper functions into a struct, which also reduces the amount of redundant SFINAE we need to perform since most overloads are checking for a cv-qualfied pair. Fixes #66714 Co-authored-by: Louis Dionne <ldionne.2@gmail.com>