Re: [C++ Patch] PR 65370

[Paolo Carlini]

... in any case, I can confirm that the below also passes testing. Not 
sure if it makes sense to add the check also to the other call site, 
can't figure out a testcase...

Thanks,
Paolo.
/////////////////
Index: cp/decl.c
===================================================================
--- cp/decl.c   (revision 221317)
+++ cp/decl.c   (working copy)
@@ -1922,7 +1922,9 @@ duplicate_decls (tree newdecl, tree olddecl, bool
        {
          /* Per C++11 8.3.6/4, default arguments cannot be added in later
             declarations of a function template.  */
-         check_redeclaration_no_default_args (newdecl);
+         if (DECL_SOURCE_LOCATION (newdecl)
+             != DECL_SOURCE_LOCATION (olddecl))
+           check_redeclaration_no_default_args (newdecl);
 
          check_default_args (newdecl);
 
Index: testsuite/g++.dg/other/default11.C
===================================================================
--- testsuite/g++.dg/other/default11.C  (revision 0)
+++ testsuite/g++.dg/other/default11.C  (working copy)
@@ -0,0 +1,11 @@
+// PR c++/65370
+
+template <typename> class C
+{
+  template <typename U>
+  C(const C<U>&, bool = false);
+};
+
+template <>
+template <typename U>
+C<int>::C(const C<U>&, bool);