https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116915

            Bug ID: 116915
           Summary: wrong code at -O{s,2,3} 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: ---

Compiler Explorer: https://godbolt.org/z/a9Pn4qq1W

It appears to be a recent regression as it doesn't reproduce with 14.2 and
earlier.


[672] % 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 20241001 (experimental) (GCC) 
[673] % 
[673] % gcctk -O1 small.c; ./a.out
[674] % 
[674] % gcctk -O3 small.c
[675] % ./a.out
Aborted
[676] % 
[676] % cat small.c
long a, b, *c = &b;
short d, e;
int main() {
  int f = 0;
  for (; f != 1; f = (short)(f - 1)) {
    d = -f;
    e = a && e;
    *c = 0 > f;
  }
  if (b != 0)
    __builtin_abort();
  return 0;
}

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