https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99832
--- Comment #12 from Jonathan Wakely <redi at gcc dot gnu.org> --- Also, I don't think we need the abi tag from from_time_t, because the mangled name of that function already depends on the type of time_t. The problem with to_time_t is that the mangled name does not depend on the return type for a non-template function. But it does depend on the parameter types, so system_clock::from_time_t(time_t) already changes mangled name when time_t changes.
