src/share/classes/com/sun/tools/javac/comp/Check.java

@@ -391,10 +391,14 @@
      *  @param pos        Position to be used for error reporting.
      *  @param found      The type that was found.
      *  @param req        The type that was required.
      */
     Type checkType(DiagnosticPosition pos, Type found, Type req) {
+        return checkType(pos, found, req, "incompatible.types");
+    }
+
+    Type checkType(DiagnosticPosition pos, Type found, Type req, String errKey) {
         if (req.tag == ERROR)
             return req;
         if (found.tag == FORALL)
             return instantiatePoly(pos, (ForAll)found, req, convertWarner(pos, found, req));
         if (req.tag == NONE)

@@ -409,11 +413,11 @@
         }
         if (req.isExtendsBound()) {
             log.error(pos, "assignment.to.extends-bound", req);
             return types.createErrorType(found);
         }
-        return typeError(pos, diags.fragment("incompatible.types"), found, req);
+        return typeError(pos, diags.fragment(errKey), found, req);
     }
 
     /** Instantiate polymorphic type to some prototype, unless
      *  prototype is `anyPoly' in which case polymorphic type
      *  is returned unchanged.