https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110376
Bug ID: 110376 Summary: Wrong code at -O1 on x86_64-linux-gnu Product: gcc Version: 14.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c Assignee: unassigned at gcc dot gnu.org Reporter: shaohua.li at inf dot ethz.ch Target Milestone: --- This seems to be a recent regression bug. gcc at -O1 produces wrong code. Compiler explorer: https://godbolt.org/z/EnMfs9oxe $ cat a.c int f, g, a, c; char k = 204; char *l = &k; short m, n; static long b; unsigned *h = &c; unsigned **i = &h; int p(char *aa) { aa[0] && aa[1] && aa[2]; return 1; } int q(char c) { char d[] = {c}; int e = p(d); return e; } int r(int j, int h) { f = h / 4; g = f * 6; return g; } short s() { return **i; } void t() { for (; r(9, *l) <= 1;) { int j; long *o = &b; *o = 0 >= 0; for (; q(0) + a > 1; a++) *o = 0 > m; j = s(); for (; a;) n = j; for (; (char)(1 + k + b) + k; --k) ; } } int main() { t(); } $ $ gcc-tk -O0 a.c &&./a.out $ $ gcc-tk -O1 a.c &&./a.out Killed - processing time exceeded $ $ gcc-tk -v Using built-in specs. COLLECT_GCC=gcc-tk COLLECT_LTO_WRAPPER=/zdata/shaoli/compilers/ccbuilder-compilers/gcc-577223aebc7acdd31e62b33c1682fe54a622ae27/libexec/gcc/x86_64-pc-linux-gnu/14.0.0/lto-wrapper Target: x86_64-pc-linux-gnu Configured with: ../configure --disable-multilib --disable-bootstrap --enable-languages=c,c++ --prefix=/zdata/shaoli/compilers/ccbuilder-compilers/gcc-577223aebc7acdd31e62b33c1682fe54a622ae27 Thread model: posix Supported LTO compression algorithms: zlib gcc version 14.0.0 20230621 (experimental) (GCC) $