https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114793
Bug ID: 114793 Summary: wrong code at -O1 with "-fschedule-insns2 -fselective-scheduling2" on x86_64-linux-gnu (the generated code hangs) 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 seems to be a recent regression as it does not reproduce with 13.2 and earlier. Compiler Explorer: https://godbolt.org/z/b3cc1MqP9 [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/14.0.1/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 14.0.1 20240421 (experimental) (GCC) [539] % [539] % gcctk -O0 small.c [540] % ./a.out [541] % [541] % gcctk -O1 -fschedule-insns2 -fselective-scheduling2 small.c [542] % timeout -s 9 10 ./a.out Killed [543] % [543] % cat small.c int printf(const char *, ...); volatile int a; int b, c, d = 1, e, f; int main() { int g = 1; for (; b; b -= d) g = e; for (; c < 2; c++) { if (g) { if (!d) printf("%d", f); continue; } a; } return 0; }