[Switch-expressions] java.lang.VerifyError: Bad type on operand stack

[srikanth-sankaran]

A problem found by the evolving stack anomaly checks in https://github.com/eclipse-jdt/eclipse.jdt.core/pull/2449

Code:

public class X {
    static void foo(String s, int i) {
        System.out.println("String = " + s + " int = " + i);
    }
    public static void main(String[] args) {

        foo("Hello", switch (42) {
        default -> {
            try {
                yield 42;
            } finally {

            }
        }
        });
    }
}

Tested on 4.29/4.30/master: All crash with:

Error: Unable to initialize main class X
Caused by: java.lang.VerifyError: Bad type on operand stack
Exception Details:
  Location:
    X.main([Ljava/lang/String;)V @2: istore_1
  Reason:
    Type 'java/lang/String' (current frame, stack[0]) is not assignable to integer
  Current Frame:
    bci: @2
    flags: { }
    locals: { '[Ljava/lang/String;' }
    stack: { 'java/lang/String' }
  Bytecode:
    0000000: 1226 3c10 2a3d 1b1c b800 28b1