https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120236

            Bug ID: 120236
           Summary: wrong code at -O{s,2,3} with "-fno-tree-fre -fipa-pta"
                    on x86_64-linux-gnu
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: ipa
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zhendong.su at inf dot ethz.ch
  Target Milestone: ---

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

This appears to affect all versions, so perhaps a known issue? 

[507] % 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/16.0.0/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 16.0.0 20250512 (experimental) (GCC) 
[508] % 
[508] % gcctk -O3 small.c; ./a.out
[509] % 
[509] % gcctk -O3 -fno-tree-fre -fipa-pta small.c
[510] % ./a.out
Aborted
[511] % 
[511] % cat small.c
int a, b, *c = &b;
int main() {
  while (a) {
    int ***d;
    *d = &c;
    a = ***d;
    if (b)
      __builtin_abort();
  }
  *c = 1;
  if (!b)
    __builtin_abort();
  return 0;
}

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