let's consider following code:

class MyType<T> {}

class MyList<T> {
    MyList<T> copyThis() { return null; }
}

class Foo<T> {
    Foo(MyType<String> a){ }
}

public class Test26  {
    public static void main(String argv[]) {
        MyList<Foo> l1 = new MyList<>();
        m2(l1, m1(
                   new Foo<>(new MyType()){ }
                 ).copyThis());
    }
    public static <T> MyList<T> m2(MyList<T> l1, MyList<T> l2) { return null; }
    public static <U> MyList<U> m1(U item) { return null; }
}

it fails to compile by javac from JDK 9 build 160 with following error:

Error:(15, 11) java: incompatible types: inference variable T has incompatible equality constraints <anonymous Foo>,Foo

But it seems that this code should compile successfully because:

1. When performing invocation type inference for m1 invocation, a temporary method is chosen according to following assertion from 18.2.1:

If the expression is a class instance creation expression or a method invocation expression, the constraint reduces to the bound set B3 which would be used to determine the expression's invocation type when targeting T, as defined in ��18.5.2. (For a class instance creation expression, the corresponding "method" used for inference is defined in ��15.9.3).

2. The temporary method return type is an anonymous class superclass as it's specified by following assertions from 15.9.3 JLS 9 draft:

... If C is an anonymous class, let D be the superclass or superinterface of C named by the class instance creation expression.

The return type of mj is ��j applied to D<F1,...,Fp>.

3. So the return type of the temporary method is Foo<F1>.

4. Unchecked conversion is necessary in order for constructor Foo to be applicable so the return type D is erased and should be Foo.

5. Thus m1 inference variable U should be inferred as Foo and m1 return type should be inferred as MyList<Foo>.

6. Finally m2 inference variable T should be inferred as Foo with no incompatible constraints.