LowerUpperBound.java

import org.checkerframework.checker.signedness.qual.*;

public class LowerUpperBound {

    public void LowerUpperBoundTest(
            @UnknownSignedness int unknown,
            @Unsigned int unsigned,
            @Signed int signed,
            @Constant int constant) {

        @UnknownSignedness int unkTest;
        @Unsigned int unsTest;
        @Signed int sinTest;
        @Constant int conTest;
        @SignednessBottom int botTest;

        unkTest = unknown + unknown;

        //:: error: (assignment.type.incompatible)
        sinTest = unknown + unknown;

        unkTest = unknown + signed;

        //:: error: (assignment.type.incompatible)
        sinTest = unknown + signed;

        sinTest = signed + signed;

        //:: error: (assignment.type.incompatible)
        conTest = signed + signed;

        sinTest = signed + constant;

        //:: error: (assignment.type.incompatible)
        conTest = signed + constant;
    }
}