Hint Resolve tc_val_pointer_nullval'.
Arguments type_is_volatile ty / .
Definition is_int32_noattr_type t :=
match t with
| Tint I32 _ {| attr_volatile := false; attr_alignas := None |} => True
| _ => False
end.

Lemma mapsto_tuint_tint:
forall sh, mapsto sh (Tint I32 Unsigned noattr) = mapsto sh (Tint I32 Signed noattr).