--- a/langtools/src/share/classes/com/sun/tools/javac/code/Types.java	Wed Jul 05 17:48:14 2017 +0200
+++ b/langtools/src/share/classes/com/sun/tools/javac/code/Types.java	Wed Aug 31 16:11:28 2011 +0100
@@ -269,10 +269,12 @@
 
     // <editor-fold defaultstate="collapsed" desc="isConvertible">
     /**
-     * Is t a subtype of or convertiable via boxing/unboxing
-     * convertions to s?
+     * Is t a subtype of or convertible via boxing/unboxing
+     * conversion to s?
      */
     public boolean isConvertible(Type t, Type s, Warner warn) {
+        if (t.tag == ERROR)
+            return true;
         boolean tPrimitive = t.isPrimitive();
         boolean sPrimitive = s.isPrimitive();
         if (tPrimitive == sPrimitive) {