Comparison between Enum and other objects should fail

package com.company.test

import groovy.transform.CompileStatic

@CompileStatic
class TestEnumGroovy {
    enum E {
        a,b
    }
    static void main(String[] args) {
        E x = E.a
        String s = "A"

        System.out.print(x == s)  // it causes an error in Java. But Groovy doesn't see the error.
    }
}