https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107273
--- Comment #2 from Zhendong Su <zhendong.su at inf dot ethz.ch> --- Another likely related instance that is miscompiled at -O1 and above. Compiler Explorer: https://godbolt.org/z/xqz7f4c7v [570] % 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) [571] % [571] % gcctk -O0 small.c; ./a.out [572] % [572] % gcctk -O1 small.c [573] % timeout -s 9 5 ./a.out Killed [574] % cat small.c int a = 1, b, c; int main() { unsigned d = 1; char e = 1, f = 150; if (f > 0) goto L2; L1: d = -(d << a || f); if (a) L2: f = ~e; char i = 1 ^ d; if (b) { e = d | c; goto L2; } if (a < 1) goto L1; while (!d) ; return 0; }
