src/share/classes/com/sun/tools/javac/jvm/ClassWriter.java

@@ -314,10 +314,18 @@
                     sigbuf.appendByte('^');
                     assembleSig(l.head);
                 }
             }
             break;
+        case FUNCTION:
+            MethodType fct = (MethodType)type;
+            sigbuf.appendByte('#');
+            assembleSig(fct.restype);
+            sigbuf.appendByte('(');
+            assembleSig(fct.argtypes);
+            sigbuf.appendByte(')');
+            break;
         case WILDCARD: {
             WildcardType ta = (WildcardType) type;
             switch (ta.kind) {
             case SUPER:
                 sigbuf.appendByte('-');