https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115925
Bug ID: 115925 Summary: wrong code at -O{2,3} with "-fno-thread-jumps" 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 regression from 13.*, and affects 14.1 and the trunk. Compiler Explorer: https://godbolt.org/z/dThxjfzf3 [521] % 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/15.0.0/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 Thread model: posix Supported LTO compression algorithms: zlib gcc version 15.0.0 20240714 (experimental) (GCC) [522] % [522] % gcctk -O2 small.c; ./a.out [523] % [523] % gcctk -O2 -fno-thread-jumps small.c [524] % ./a.out 1 [525] % cat small.c int printf(const char *, ...); int a, b, c = 1, d = 1, e, g; char f; int main() { int h = 10, i; j: if (h < e) { printf("%d\n", c); return 0; } i = -1; if (d) i = h; h = b = -2; a = (b ^ i) | (c || f); if (i <= a) g = ~i; if (a > 0) goto j; return 0; }