The new diamond implementation generates spurious raw types diagnostics:

class Foo<X> {
   Foo() {}
   Foo<String> f = new Foo<>();
}

this produces the following output (when compiled with -Xlint):

TestX.java:3: warning: [rawtypes] found raw type: Foo
   Foo<String> f = new Foo<>();
                          ^
  missing type parameters for generic class Foo<X>
  where X is a type-variable:
    X extends Object declared in class Foo
1 warning