[Bug libstdc++/106275] unordered_map with std::string key, std::hash<std::string>, and custom equality predicate weirdness

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106275

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> ---
The difference in behaviour is due to r12-6272-ge3ef832a9e8d6a