commit 668c1f7aebfcc94faee89fd36e2a2258095761c3
Author: Jason Merrill <jason@redhat.com>
Date:   Thu Dec 24 16:26:59 2009 -0500

    	PR c++/38392
    	* pt.c (tsubst_friend_function): Instatiate a friend that has already
    	been used.

diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 85ad539..958099c 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -7141,11 +7141,18 @@ tsubst_friend_function (tree decl, tree args)
 	      DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
 
 	      if (TREE_CODE (old_decl) != TEMPLATE_DECL)
-		/* We should have called reregister_specialization in
-		   duplicate_decls.  */
-		gcc_assert (retrieve_specialization (new_template,
-						     new_args, 0)
-			    == old_decl);
+		{
+		  /* We should have called reregister_specialization in
+		     duplicate_decls.  */
+		  gcc_assert (retrieve_specialization (new_template,
+						       new_args, 0)
+			      == old_decl);
+
+		  /* Instantiate it if the global has already been used.  */
+		  if (DECL_ODR_USED (old_decl))
+		    instantiate_decl (old_decl, /*defer_ok=*/true,
+				      /*expl_inst_class_mem_p=*/false);
+		}
 	      else
 		{
 		  tree t;
diff --git a/gcc/testsuite/g++.dg/template/friend51.C b/gcc/testsuite/g++.dg/template/friend51.C
new file mode 100644
index 0000000..3e0540e
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/friend51.C
@@ -0,0 +1,16 @@
+// PR c++/38392
+
+void Function();
+
+int main()
+{
+  Function();
+}
+
+template <typename T>
+struct Test
+{
+  friend void Function() { }
+};
+
+template class Test<int>;