https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115671
Bug ID: 115671
Summary: wrong code at -O1 with "-fgcse -fno-inline
-fschedule-insns" on x86_64-linux-gnu
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
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 doesn't reproduce with 14.1.
Compiler Explorer: https://godbolt.org/z/Ev6hsWhE1
[648] % 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 20240626 (experimental) (GCC)
[649] %
[649] % gcctk -O1 small.c; ./a.out
[650] %
[650] % gcctk -O1 -fgcse -fno-inline -fschedule-insns small.c
[651] % ./a.out
Aborted
[652] %
[652] % cat small.c
int printf(const char *, ...);
int a, b, c, d, e;
short f[2];
int g(int h, int i) { return 0; }
int j(int h, int i) { return i; }
void k() {
int l;
for (; b < 1; b++) {
l = g(a, e);
c = l < a;
e = j(f[1 + b], 2);
d = a || d;
if (j(0, 1))
return;
}
}
int main() {
k();
if (c != 0)
__builtin_abort();
return 0;
}
