Let's consider following example:

    class B<V> {}

    class Foo<E extends B<E>> {
        public Foo<E> complexMethod(E a) { return this; }
    }

    public class Test65 {
        public static void check() {
            Foo t4 = new Foo<>() {
            };
        }
    }

This code successfully compiles on JDK9b60. However according to my understanding the compilation should have failed as per new spec.

The reasons why I think that the compilation should have failed are presented below.

E is inferred as B<Y>, where Y is a fresh type variable with the upper bound B<Y>. If this is correct the given code should cause compilation failure according to following new assertions presented in the JDK-8073593 issue comment:

    ***It is a compile-time error if the superclass or superinterface type of the anonymous class, T, or any subexpression of T, has one of the following forms:
    - A type variable (4.4) that was not declared as a type parameter (such as a type variable produced by capture conversion (5.1.10))
    - An intersection type (4.9)
    - A class or interface type, where the class or interface declaration is not accessible from the class or interface in which the expression appears.***
    The term "subexpression" includes type arguments of parameterized types (4.5), bounds of wildcards (4.5.1), and element types of array types (10.1). It excludes bounds of type variables.***

The reason for this is that anonymous class super type, which is parameterized, has a type argument (subexpression) being a type variable which was not declared as a type parameter.

The fact that E is inferred as a type variable with the upper bound becomes more obvious if we decide to override complexMethod:

        Foo t4 = new Foo<>() {
            public Foo<? extends B> complexMethod(B a){ return this; }
            //public Foo<B> complexMethod(B a){ return this; } ;//this causes compilation failure
        };

In this case providing return type as Foo<B> causes compilation failure. Only specifying the return type as Foo<? extends B> gets compilation to succeed.

In general the reasons why I believe that E is inferred here as B<Y> are presented below (just meaningful steps are presented).

1. Initial bounds set created from type parameter bounds contains following items as per JLS 18.1.3:

    e :< B<e> (e - is inference variable);
    e :< Object (this is added because e had no proper upper bounds);

2. Then these bounds are processed by resolution process (JLS 18.4). During resolution e :< Object causes instantiation e=Object according to following assertion from JLS 18.4:

    Otherwise, where ai has proper upper bounds U1, ..., Uk, Ti = glb(U1, ..., Uk)

3. Incorporating e=Object causes following new constraint to be added Object :< B<Object> according to following assertion from JLS 18.3.1:

    a = U and S <: T imply ‹S[a:=U] <: T[a:=U]›

5. Constraint Object :< B<Object> reduces to false causing the second resolution attempt to take effect according to following assertion from JLS 18.4:

    Otherwise, the result contains the bound false, so a second attempt is made to instantiate { a1, ..., an } by performing the step below.

4. Fresh type variable Y with upper bound B<Y> is introduced according to assertions from JLS 18.4 presented below (Y upper bound is glb(Object,B<e>[e:=Y]) = B<e>[e:=Y] = B<Y>):

    then let Y1, ..., Yn be fresh type variables whose bounds are as follows:
    * For all i (1 ≤ i ≤ n), where ai has upper bounds U1, ..., Uk, let the upper bound of Yi be glb(U1 q, ..., Uk q), where q is the substitution [a1:=Y1, ..., an:=Yn].

5. Finally e is instantiated as a fresh type variable Y with the upper bound B<Y> according to the following assertion from JLS 18.4:

    Otherwise, for all i (1 ≤ i ≤ n), all bounds of the form G<..., ai, ...> = capture(G<...>) are removed from the current bound set, and the bounds a1 = Y1, ..., an = Yn are incorporated.