https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107273
Bug ID: 107273 Summary: wrong code at -O3 on x86_64-linux-gnu Product: gcc Version: unknown Status: UNCONFIRMED Severity: normal Priority: P3 Component: tree-optimization Assignee: unassigned at gcc dot gnu.org Reporter: zhendong.su at inf dot ethz.ch Target Milestone: --- It appears to be a recent regression. Compiler Explorer: https://godbolt.org/z/Mo8sPhYW7 [538] % gcctk -v Using built-in specs. COLLECT_GCC=gcctk COLLECT_LTO_WRAPPER=/local/suz-local/software/local/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/13.0.0/lto-wrapper Target: x86_64-pc-linux-gnu Configured with: ../gcc-trunk/configure --disable-bootstrap --enable-checking=yes --prefix=/local/suz-local/software/local/gcc-trunk --enable-sanitizers --enable-languages=c,c++ --disable-werror --enable-multilib --with-system-zlib Thread model: posix Supported LTO compression algorithms: zlib gcc version 13.0.0 20221015 (experimental) [master r13-3311-gbaeec7cc83b] (GCC) [539] % [539] % gcctk -O2 small.c; ./a.out [540] % [540] % gcctk -O3 small.c [541] % ./a.out Segmentation fault [542] % [542] % cat small.c int printf(const char *, ...); int a[1] = {1}; short b, c = 5500; int d; long e; char f = 1; int main() { while (1) { long g = b < 1; e = g; break; } for (; f; f--) { if (e) { d = -(6L | -(c & 1000)); } char h = d; if (b) b = 0; if (d < 200) while (1) printf("%d", a[c]); short i = h * 210; c = i; } return 0; }