diff --git a/src/type_of.rs b/src/type_of.rs
index 84d57838512..a30bce0a313 100644
--- a/src/type_of.rs
+++ b/src/type_of.rs
@@ -339,7 +339,8 @@ impl<'tcx> LayoutGccExt<'tcx> for TyAndLayout<'tcx> {
             return pointee;
         }
 
-        let result = Ty::ty_and_layout_pointee_info_at(*self, cx, offset);
+        let assume_valid_ptr = true;
+        let result = Ty::ty_and_layout_pointee_info_at(*self, cx, offset, assume_valid_ptr);
 
         cx.pointee_infos.borrow_mut().insert((self.ty, offset), result);
         result