https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90913
--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> ---
Somehow we end up with
(gdb) p debug_tree (maskt)
<ssa_name 0x7ffff6e35798
type <boolean_type 0x7ffff6c52b28 logical(kind=1) public unsigned QI
size <integer_cst 0x7ffff6c3dc60 constant 8>
unit-size <integer_cst 0x7ffff6c3dc78 constant 1>
align:8 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0x7ffff6c52b28 precision:1 min <integer_cst 0x7ffff6c3deb8 0> max <integer_cst
0x7ffff6c3dee8 1>>
visited
def_stmt _157 = _155 & _21;
version:157>
this must be a latent issue.