https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120358
--- Comment #30 from Alexander Monakov <amonakov at gcc dot gnu.org> ---
Forgot to mention that the offending match.pd rule is
/* Simplify pointer equality compares using PTA. */
(for neeq (ne eq)
(simplify
(neeq @0 @1)
(if (POINTER_TYPE_P (TREE_TYPE (@0))
&& ptrs_compare_unequal (@0, @1))
{ constant_boolean_node (neeq != EQ_EXPR, type); })))
and ptrs_compare_unequal unexpectedly returns true (as already hinted in
comment #5)
