[Bug libstdc++/89624] HLE acquire/release bits in std::memory_order don't work with -fshort-enums or -fstrict-enums

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89624

--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> ---
It's also a mostly-harmless ABI change for C++17 down, because the underlying
type without -fshort-enums changes from implicitly being chosen as unsigned
int, to explicitly being specified as int.