diff -r f74e4269a50a -r 858ae8fec72f src/share/classes/com/sun/tools/javac/comp/Attr.java
--- a/src/share/classes/com/sun/tools/javac/comp/Attr.java	Fri Jun 24 13:52:14 2011 -0700
+++ b/src/share/classes/com/sun/tools/javac/comp/Attr.java	Thu Jun 30 12:00:53 2011 -0700
@@ -3388,6 +3388,13 @@
         }
 
         @Override
+        public void visitAssignop(JCAssignOp that) {
+            if (that.operator == null)
+                that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
+            super.visitAssignop(that);
+        }
+
+        @Override
         public void visitBinary(JCBinary that) {
             if (that.operator == null)
                 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);