re PR c++/61507 (GCC does not compile function with parameter pack.)

	PR c++/61507
	* pt.c (resolve_overloaded_unification): Preserve
	ARGUMENT_PACK_EXPLICIT_ARGS.

From-SVN: r211808

gcc/cp/ChangeLog

+2014-06-18  Jason Merrill  <jason@redhat.com>
+
+	PR c++/61507
+	* pt.c (resolve_overloaded_unification): Preserve
+	ARGUMENT_PACK_EXPLICIT_ARGS.
+
 2014-06-18  Jakub Jelinek  <jakub@redhat.com>
 
 	* cp-gimplify.c (cxx_omp_finish_clause): Add a gimple_seq *

gcc/cp/pt.c

@@ -16838,7 +16838,16 @@ resolve_overloaded_unification (tree tparms,
       int i = TREE_VEC_LENGTH (targs);
       for (; i--; )
 	if (TREE_VEC_ELT (tempargs, i))
-	  TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
+	  {
+	    tree old = TREE_VEC_ELT (targs, i);
+	    tree new_ = TREE_VEC_ELT (tempargs, i);
+	    if (new_ && old && ARGUMENT_PACK_P (old)
+		&& ARGUMENT_PACK_EXPLICIT_ARGS (old))
+	      /* Don't forget explicit template arguments in a pack.  */
+	      ARGUMENT_PACK_EXPLICIT_ARGS (new_)
+		= ARGUMENT_PACK_EXPLICIT_ARGS (old);
+	    TREE_VEC_ELT (targs, i) = new_;
+	  }
     }
   if (good)
     return true;

gcc/testsuite/g++.dg/cpp0x/variadic159.C

+// PR c++/61507
+// { dg-do compile { target c++11 } }
+
+struct A {
+  void foo(const int &);
+  void foo(float);
+};
+
+template <typename... Args>
+void bar(void (A::*memfun)(Args...), Args... args);
+
+void go(const int& i) {
+  bar<const int &>(&A::foo, i);
+}