re PR c++/55542 (g++ segmentation fault)

	PR c++/55542
	* pt.c (make_ith_pack_parameter_name): Return NULL if
	name is NULL.
	(tsubst_decl): Call make_ith_pack_parameter_name even if
	DECL_NAME is NULL.

	* g++.dg/cpp0x/vt-55542.C: New test.

From-SVN: r194010

gcc/cp/ChangeLog

+2012-12-01  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/55542
+	* pt.c (make_ith_pack_parameter_name): Return NULL if
+	name is NULL.
+	(tsubst_decl): Call make_ith_pack_parameter_name even if
+	DECL_NAME is NULL.
+
 2012-11-29  Jason Merrill  <jason@redhat.com>
 
 	PR c++/53137

gcc/cp/pt.c

@@ -2905,6 +2905,8 @@ make_ith_pack_parameter_name (tree name, int i)
   char* newname;
   int newname_len;
 
+  if (name == NULL_TREE)
+    return name;
   snprintf (numbuf, NUMBUF_LEN, "%i", i);
   newname_len = IDENTIFIER_LENGTH (name)
 	        + strlen (numbuf) + 2;
@@ -10261,10 +10263,9 @@ tsubst_decl (tree t, tree args, tsubst_flags_t complain)
                 /* Get the Ith type.  */
                 type = TREE_VEC_ELT (expanded_types, i);
 
-                if (DECL_NAME (r))
-                  /* Rename the parameter to include the index.  */
-                  DECL_NAME (r) =
-                    make_ith_pack_parameter_name (DECL_NAME (r), i);
+		/* Rename the parameter to include the index.  */
+		DECL_NAME (r)
+		  = make_ith_pack_parameter_name (DECL_NAME (r), i);
               }
             else if (!type)
               /* We're dealing with a normal parameter.  */

gcc/testsuite/ChangeLog

+2012-12-01  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/55542
+	* g++.dg/cpp0x/vt-55542.C: New test.
+
 2012-11-30  Eric Botcazou  <ebotcazou@adacore.com>
 
 	* gnat.dg/specs/pack9.ads: New test.

gcc/testsuite/g++.dg/cpp0x/vt-55542.C

+// PR c++/55542
+// { dg-options "-std=c++11" }
+
+template <typename ... P>
+struct B
+{
+  template <typename O>
+  B (O *o, void (O::*f) (P ... p)) {}
+};
+class C
+{
+  void foo (void *, int);
+  template <typename ... A>
+  void bar (A ... a);
+  B <void *> c;
+  B <void *, int> d;
+  C (int) : c (this, &C::bar), d (this, &C::foo) {}
+};
+template <typename ... A>
+void C::bar (A ...)
+{
+}