javac generates the same error message twice for this code:

value class C {
    int i;
    C() {
        m(this);
        i = 0;
    }

    void m(C c) {}
}

although with a slightly different position:

ValhallaTest1.java:4: error: value class instance should not be passed around before being fully initialized
        m(this);
          ^
ValhallaTest1.java:4: error: value class instance should not be passed around before being fully initialized
        m(this);
         ^
2 errors