re PR c++/45012 (Invalid ambiguity on partial class specialization matching)

	PR c++/45102
	* pt.c (tsubst_copy_and_build) [CONST_DECL]: Don't pull out
	constant value if we're still in a template.

From-SVN: r179230

gcc/cp/ChangeLog

 2011-09-26  Jason Merrill  <jason@redhat.com>
 
+	PR c++/45102
+	* pt.c (tsubst_copy_and_build) [CONST_DECL]: Don't pull out
+	constant value if we're still in a template.
+
 	PR c++/46105
 	* typeck.c (structural_comptypes): Ignore cv-quals on typename scope.
 

gcc/cp/pt.c

@@ -13916,7 +13916,7 @@ tsubst_copy_and_build (tree t,
       t = tsubst_copy (t, args, complain, in_decl);
       /* As in finish_id_expression, we resolve enumeration constants
 	 to their underlying values.  */
-      if (TREE_CODE (t) == CONST_DECL)
+      if (TREE_CODE (t) == CONST_DECL && !processing_template_decl)
 	{
 	  used_types_insert (TREE_TYPE (t));
 	  return DECL_INITIAL (t);

gcc/testsuite/ChangeLog

 2011-09-26  Jason Merrill  <jason@redhat.com>
 
+	PR c++/45012
+	* g++.dg/template/partial13.C: New.
+
 	PR c++/46105
 	* g++.dg/template/partial12.C: New.
 

gcc/testsuite/g++.dg/template/partial13.C

+// PR c++/45012
+
+template <bool B, class T=void> struct enable_if;
+
+template <class T>
+struct enable_if<true,T>
+{
+  typedef T type;
+};
+
+enum { RUNTIME = 0 };
+// it compiles with the previous line commented out and the next commented in
+// static const int RUNTIME=0;
+
+template <class T, class U, class EN=void> struct foo;
+
+template <template<int> class V, int M>
+struct foo<V<M>,V<M>, typename enable_if<M==RUNTIME||M==2>::type> {};
+
+template <template<int> class V1, template<int> class V2, int M>
+struct foo<V1<M>,V2<M>, typename enable_if<M==RUNTIME||M==2>::type> {};
+
+template <int M> struct bar {};
+
+foo<bar<2>,bar<2> > x;