diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 675aca54e272..7d02bb5b1e65 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,8 @@
+2008-01-21  Jason Merrill  <jason@redhat.com>
+
+	PR c++/33959
+	* pt.c (tsubst_aggr_type): Make sure our context is complete.
+
 2008-01-02  Volker Reichelt  <reichelt@netcologne.de>
 
 	Backport:
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index a837ba2076dc..9a6f2fc9cc69 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -6325,8 +6325,13 @@ tsubst_aggr_type (tree t,
 	     up.  */
 	  context = TYPE_CONTEXT (t);
 	  if (context)
-	    context = tsubst_aggr_type (context, args, complain,
-					in_decl, /*entering_scope=*/1);
+	    {
+	      context = tsubst_aggr_type (context, args, complain,
+					  in_decl, /*entering_scope=*/1);
+	      /* If context is a nested class inside a class template,
+	         it may still need to be instantiated (c++/33959).  */
+	      complete_type (context);
+	    }
 
 	  /* Then, figure out what arguments are appropriate for the
 	     type we are trying to find.  For example, given:
diff --git a/gcc/testsuite/g++.dg/template/nested5.C b/gcc/testsuite/g++.dg/template/nested5.C
new file mode 100644
index 000000000000..3850fdace3a5
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/nested5.C
@@ -0,0 +1,19 @@
+// PR c++/33959
+
+template <typename T> struct A
+{
+  struct C
+  {
+    template <typename U> struct D {};
+  };
+  template <typename S> static C::D<S> bar (S const &);
+};
+
+struct E {};
+
+int
+main ()
+{
+  E e;
+  A<E>::bar (e);
+}