https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119011
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |jakub at gcc dot gnu.org
--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to Alejandro Colomar from comment #3)
> unsigned long == -1 does The Right Thing(tm). The -1 is first
> sign-extended, and afterwards converted, which is what programmers want.
No, it is exactly something the warning should warn about.
If you want to compare against all ones time_t, just use ~(time_t)0 or similar.