https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118138

            Bug ID: 118138
           Summary: wrong code at -O3 with "-fno-inline" 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: ---

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

Compiler Explorer: https://godbolt.org/z/EMvd5nnMb

[573] % 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 20241219 (experimental) (GCC) 
[574] % 
[574] % gcctk -O3 small.c; ./a.out
[575] % 
[575] % gcctk -O3 -fno-inline small.c
[576] % ./a.out
Aborted
[577] % 
[577] % cat small.c
unsigned a = -1;
int b, e, c = 1;
unsigned long d;
long f(long g) { return g; }
static long h(unsigned g) {
  for (; b < 8; b++)
    d = f(g);
  e = a < d;
  if (e)
    c = 0;
  return 0;
}
static void i(short g) { h(g); }
int main() {
  i(-1);
  if (c != 1)
    __builtin_abort();
  return 0;
}

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