FULL PRODUCT VERSION :
java version "1.6.0"
Java(TM) SE Runtime Environment (build 1.6.0-b105)
Java HotSpot(TM) Client VM (build 1.6.0-b105, mixed mode, sharing)
javac 1.6.0


ADDITIONAL OS VERSION INFORMATION :
Linux toth 2.6.15-52-386 #1 PREEMPT Mon Jun 9 17:24:46 UTC 2008 i686 GNU/Linux
a

A DESCRIPTION OF THE PROBLEM :
Running javac on the attached program causes a type error. It appears to be caused by the occurrence of "U" in the generic declaration "<B extends Bar<U,B>>" being treated as a binding occurrence rather than as a free occurrence, thus causing the unification of V with itself in "x.<Y>bar(y)" to fail. If U and V are removed, the problem goes away. If the upper bound on B is removed, the problem goes away.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
javac the attached code, note type error.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Successful compilation.
ACTUAL -
Type error.

ERROR MESSAGES/STACK TRACES THAT OCCUR :
Test.java:5: <B>bar(Bar<V,B>) in Bar<V,X> cannot be applied to <Y>(Bar<V,Y>)
    void foo() { x.<Y>bar(y); }
                  ^


REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
class Foo<V,X extends Bar<V,X>,Y extends Bar<V,Y>> {

    Bar<V,X> x;
    Bar<V,Y> y;
    void foo() { x.<Y>bar(y); }

}

interface Bar<U,A> {
    <B extends Bar<U,B>> void bar(Bar<U,B> x);
}


---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
The version of javac distributed with eclipse does not appear to have this bug.