PR c++/51476 - ICE on PTRMEM_CST as template argument in c++11

gcc/cp/

	PR c++/51476
	* pt.c (convert_nontype_argument): Don't call maybe_constant_value
	for PTRMEM_CST nodes.

gcc/testsuite/

	PR c++/51476
	* g++.dg/cpp0x/ptrmem-cst-arg1.C: New test.

From-SVN: r182324

gcc/cp/ChangeLog

+2011-12-14  Dodji Seketeli  <dodji@redhat.com>
+
+	PR c++/51476
+	* pt.c (convert_nontype_argument): Don't call maybe_constant_value
+	for PTRMEM_CST nodes.
+
 2011-12-13  Jason Merrill  <jason@redhat.com>
 
 	PR c++/51406

gcc/cp/pt.c

@@ -5720,11 +5720,15 @@ convert_nontype_argument (tree type, tree expr, tsubst_flags_t complain)
      to a null value, but otherwise still need to be of a specific form.  */
   if (cxx_dialect >= cxx0x)
     {
-      if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
+      if (TREE_CODE (expr) == PTRMEM_CST)
+	/* A PTRMEM_CST is already constant, and a valid template
+	   argument for a parameter of pointer to member type, we just want
+	   to leave it in that form rather than lower it to a
+	   CONSTRUCTOR.  */;
+      else if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
 	expr = maybe_constant_value (expr);
       else if (TYPE_PTR_P (type)
-	       || (TYPE_PTR_TO_MEMBER_P (type)
-		   && TREE_CODE (expr) != PTRMEM_CST))
+	       || TYPE_PTR_TO_MEMBER_P (type))
 	{
 	  tree folded = maybe_constant_value (expr);
 	  if (TYPE_PTR_P (type) ? integer_zerop (folded)

gcc/testsuite/ChangeLog

+2011-12-14  Dodji Seketeli  <dodji@redhat.com>
+
+	PR c++/51476
+	* g++.dg/cpp0x/ptrmem-cst-arg1.C: New test.
+
 2011-12-13  Jason Merrill  <jason@redhat.com>
 
 	PR c++/51406

gcc/testsuite/g++.dg/cpp0x/ptrmem-cst-arg1.C

+// Origin PR c++/51476
+// { dg-options "-std=c++11" }
+
+template<int> struct A {};                                                               
+struct B
+{
+    int i;
+    A<&B::i> a; // { dg-error "could not convert template argument" }
+};