[Bug tree-optimization/97901] New: ICE at -Os: verify_gimple failed

[zhendong.su at inf dot ethz.ch]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97901

            Bug ID: 97901
           Summary: ICE at -Os: verify_gimple failed
           Product: gcc
           Version: 11.0
            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: ---

[539] % 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/11.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-trunk/configure --disable-bootstrap
--prefix=/local/suz-local/software/local/gcc-trunk --enable-languages=c,c++
--disable-werror --enable-multilib --with-system-zlib
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 11.0.0 20201119 (experimental) [master revision
25bb75f841c:9f334878639:700337494e1b0d5ff608e1a3c77852381e264653] (GCC)
[540] %
[540] % gcctk -Os small.c
small.c: In function ‘main’:
small.c:3:5: error: invalid address operand in ‘mem_ref’
    3 | int main() {
      |     ^~~~
a[0];

# VUSE <.MEM_22>
_5 = a[0];
during GIMPLE pass: loopdone
small.c:3:5: internal compiler error: verify_gimple failed
0xd62975 verify_gimple_in_cfg(function*, bool)
        ../../gcc-trunk/gcc/tree-cfg.c:5461
0xc118ee execute_function_todo
        ../../gcc-trunk/gcc/passes.c:2039
0xc127d2 execute_todo
        ../../gcc-trunk/gcc/passes.c:2093
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
[541] %
[541] % cat small.c
int a[1], b, *c, *d;

int main() {
L:
  d = c;
  for (b = 0; b < 2; b++)
    d = &a[0];
  if (c)
    goto L;
  if (*d)
    __builtin_abort ();
  return 0;
}