[Bug c/109604] New: ice during GIMPLE pass: phiopt

["dcb314 at hotmail dot com" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109604

            Bug ID: 109604
           Summary: ice during GIMPLE pass: phiopt
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: dcb314 at hotmail dot com
  Target Milestone: ---

For this C code:

nilfs_bmap_find_target_seq_bmap;
unsigned long nilfs_bmap_find_target_seq_bmap_0;
unsigned long nilfs_bmap_find_target_seq() {
  if (nilfs_bmap_find_target_seq_bmap &&
      nilfs_bmap_find_target_seq_bmap_0 + nilfs_bmap_find_target_seq_bmap)
    return nilfs_bmap_find_target_seq_bmap_0 + nilfs_bmap_find_target_seq_bmap;
  else
    return 0;
}

compiled by recent gcc trunk, does this:

$ ../results/bin/gcc -c -w -O1 bug908.c 
bug908.c: In function ‘nilfs_bmap_find_target_seq’:
bug908.c:9:1: error: definition in block 3 does not dominate use in block 4
    9 | }
      | ^
for SSA_NAME: _5 in statement:
# VUSE <.MEM_10(D)>
return _5;
during GIMPLE pass: phiopt
bug908.c:9:1: internal compiler error: verify_ssa failed
0x107ae4f verify_ssa(bool, bool)
        ../../trunk.year/gcc/tree-ssa.cc:1211

This seems to have broken between git hash g:7e26fd6bcd39f53b
and g:ff8f95449350372b, which is 6 revisions.