https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119186
Xi Ruoyao <xry111 at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |xry111 at gcc dot gnu.org Status|UNCONFIRMED |RESOLVED Resolution|--- |INVALID --- Comment #1 from Xi Ruoyao <xry111 at gcc dot gnu.org> --- With -fsanitize=undefined: t.c:13:30: runtime error: passing zero to ctz(), which is not a valid argument Quote from the GCC manual: -- Built-in Function: int __builtin_ctz (unsigned int X) Returns the number of trailing 0-bits in X, starting at the least significant bit position. If X is 0, the result is undefined.