[gcc r17-3507] c++: improve SFINAE in lookup_destructor

https://gcc.gnu.org/g:5dc5d050b35b35233b92217c8ebf9dd3abf0bf50

commit r17-3507-g5dc5d050b35b35233b92217c8ebf9dd3abf0bf50
Author: Jason Merrill <[email protected]>
Date:   Thu Aug 20 14:14:38 2026 -0400

    c++: improve SFINAE in lookup_destructor
    
    This doesn't fix anything currently, but while working on another change I
    noticed that we weren't passing complain down here.
    
    gcc/cp/ChangeLog:
    
            * typeck.cc (lookup_destructor): Pass complain to lookup_member.

Diff:
---
 gcc/cp/typeck.cc | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/gcc/cp/typeck.cc b/gcc/cp/typeck.cc
index 5bde051b9b36..712b95ab245c 100644
--- a/gcc/cp/typeck.cc
+++ b/gcc/cp/typeck.cc
@@ -3251,7 +3251,9 @@ lookup_destructor (tree object, tree scope, tree dtor_name,
     }
   expr = lookup_member (dtor_type, complete_dtor_identifier,
 			/*protect=*/1, /*want_type=*/false,
-			tf_warning_or_error);
+			complain);
+  if (expr == error_mark_node)
+    return error_mark_node;
   if (!expr)
     {
       if (complain & tf_error)