https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106115

            Bug ID: 106115
           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: ---

Another recent regression from 12.*.
It might be related to PR 106114.

[547] % 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/13.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-trunk/configure --disable-bootstrap
--prefix=/local/suz-local/software/local/gcc-trunk --enable-sanitizers
--enable-languages=c,c++ --disable-werror --enable-multilib --with-system-zlib
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 13.0.0 20220628 (experimental) [master r13-1313-gf9764ea128c] (GCC) 
[548] % 
[548] % gcctk -O1 small.c; ./a.out
[549] % 
[549] % gcctk -O2 small.c
[550] % ./a.out
65535
[551] % 
[551] % cat small.c
int printf(const char *, ...);
int a, b = 1041281974;
unsigned short c;
int main()
{
  int d, e = b;
  b = ~-~a;
  a = c = -~b;
  if (c < 65529) {
    printf("%d\n", d);
    e = 0;
  }
  if (b)
    d = a;
  if (((e > 1041281974) && d) || e < 1041281974)
    printf("%d\n", c);
  return 0;
}

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