https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70104
--- Comment #2 from Niks <np199113 at gmail dot com> --- (In reply to Jakub Jelinek from comment #1) > 'a' || 'A' is 1, so there is no reason to give an error about it. > The error in the second case is because you have two case labels with the > same value, 1. That is not allowed in a switch. Thank you.!