https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80379
--- Comment #3 from Jan Hubicka <hubicka at gcc dot gnu.org> --- The problem here is that the hint is output at decl merging and -fno-strict-aliasing is a function local flag. At that time we do not even know what functions will be since units are not streamed in yet. This means that we do not know if some unit has function that is -fno-strict-aliasing. So supressing the warning does not fit the implementation very easily :(
