Re: C++ PATCH for c++/81359, Unparsed NSDMI error in SFINAE context

[Jason Merrill]

On Thu, Aug 10, 2017 at 12:13 AM, Markus Trippelsdorf
<mar...@trippelsdorf.de> wrote:
> On 2017.08.09 at 14:30 -0400, Jason Merrill wrote:
>> The issue here is that we try to determine the EH specification of
>> B::C::C() from within SFINAE context, and we can't determine it yet
>> because the NSDMI for B::C::i hasn't been parsed yet.  This patch
>> allows that determination to fail quietly in SFINAE context; we'll try
>> again the next time it is needed.
>
> Thanks.
>
> Unfortunately it breaks the following testcase:

Fixed thus:

commit 98a57ff77c97446c0477bea2aed831b62a0726a6
Author: Jason Merrill <ja...@redhat.com>
Date:   Thu Aug 10 12:23:12 2017 -0700

            Fix regression from 81359 patch.
    
            * method.c (synthesized_method_walk): Don't diagnose lack of
            operator delete.

diff --git a/gcc/cp/method.c b/gcc/cp/method.c
index bff9605..809ebc8 100644
--- a/gcc/cp/method.c
+++ b/gcc/cp/method.c
@@ -1693,12 +1693,18 @@ synthesized_method_walk (tree ctype, 
special_function_kind sfk, bool const_p,
 
       if (check_vdtor && type_has_virtual_destructor (BINFO_TYPE (base_binfo)))
        {
-         fn = locate_fn_flags (ctype, cp_operator_id (DELETE_EXPR),
-                               ptr_type_node, flags, complain);
          /* Unlike for base ctor/op=/dtor, for operator delete it's fine
             to have a null fn (no class-specific op delete).  */
-         if (fn && fn == error_mark_node && deleted_p)
-           *deleted_p = true;
+         fn = locate_fn_flags (ctype, cp_operator_id (DELETE_EXPR),
+                               ptr_type_node, flags, tf_none);
+         if (fn && fn == error_mark_node)
+           {
+             if (complain & tf_error)
+               locate_fn_flags (ctype, cp_operator_id (DELETE_EXPR),
+                                ptr_type_node, flags, complain);
+             if (deleted_p)
+               *deleted_p = true;
+           }
          check_vdtor = false;
        }
     }
diff --git a/gcc/testsuite/g++.dg/inherit/vdtor1.C 
b/gcc/testsuite/g++.dg/inherit/vdtor1.C
new file mode 100644
index 0000000..caba17f
--- /dev/null
+++ b/gcc/testsuite/g++.dg/inherit/vdtor1.C
@@ -0,0 +1,7 @@
+struct A {
+  void operator delete(void *, unsigned long);
+};
+struct B : A {
+  virtual ~B();
+};
+struct C : B {};