pt.c (tsubst_copy): Only do typename overloading on an IDENTIFIER_NODE that…

pt.c (tsubst_copy): Only do typename overloading on an IDENTIFIER_NODE that happens to look like a...

	* pt.c (tsubst_copy): Only do typename overloading on an
	IDENTIFIER_NODE that happens to look like a typename if it actually
	has a type for us to use.
avoid problems w/ SGI STL headers that have variables like __opr or __op1

From-SVN: r21978

gcc/cp/ChangeLog

+1998-08-25  Brendan Kehoe  <brendan@cygnus.com>
+
+	* pt.c (tsubst_copy): Only do typename overloading on an
+	IDENTIFIER_NODE that happens to look like a typename if it actually
+	has a type for us to use.
+
 1998-08-25  Jason Merrill  <jason@yorick.cygnus.com>
 
 	* typeck.c (comp_cv_target_types): Split out...

gcc/cp/pt.c

@@ -5971,7 +5971,10 @@ tsubst_copy (t, args, in_decl)
       return tsubst (t, args, in_decl);
 
     case IDENTIFIER_NODE:
-      if (IDENTIFIER_TYPENAME_P (t))
+      if (IDENTIFIER_TYPENAME_P (t)
+	  /* Make sure it's not just a variable named `__opr', for instance,
+	     which can occur in some existing code.  */
+	  && TREE_TYPE (t))
 	return build_typename_overload
 	  (tsubst (TREE_TYPE (t), args, in_decl));
       else