https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110365

            Bug ID: 110365
           Summary: wrong code at -O2 and -O3 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 recent regression.

Compiler Explorer: https://godbolt.org/z/aP9aMrsGq

[725] % gcctk -v
Using built-in specs.
COLLECT_GCC=gcctk
COLLECT_LTO_WRAPPER=/local/home/suz/suz-local/software/local/gcc-trunk/bin/../libexec/gcc/x86_64-pc-linux-gnu/14.0.0/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
--disable-multilib
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 14.0.0 20230622 (experimental) [master r14-924-gd709841ae0f] (GCC) 
[726] % 
[726] % gcctk -O1 small.c; ./a.out
[727] % 
[727] % gcctk -O2 small.c
[728] % ./a.out
Aborted
[729] % 
[729] % cat small.c
int a = 1;
void b() {
  int *c = &a, d = a;
  if (a < -1)
    d = a + d;
  a = d;
  if (a > 0)
    *c = 1;
  int e = -a;
  if (e < a) {
    e = a;
    if (!a)
      __builtin_abort();
  }
  a = e;
}
int main() {
  b();
  if (a != 1)
    __builtin_abort();
  return 0;
}

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