https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100499
--- Comment #9 from bin cheng <amker at gcc dot gnu.org> --- Seems we have a long standing bug in fold-const.c:multiple_of_p in case of wrapping types. Take unsigned int as an example: (0xfffffffc * 0x3) % 0x3 = 0x1 But multiple_of_p returns true here. The same issue also stands for MINUS_EXPR and PLUS_EXPR. Given multiple_of_p is used elsewhere, the fix might break existing optimizations. Especially, number of loop iterations is computed in unsigned types
