Name: dgC58589 Date: 12/17/97


The following code works great when you use
javac, but produces unexpected results when using
javac -O

class Test
{
    public static void main (String argc[])
    {
        System.out.println ("test (0) = " + test (0));
        System.out.println ("test (1) = " + test (1));
        System.out.println ("test (0) = " + test (0));
        System.out.println ("test (1) = " + test (1));
    }

    private static String test (int i)
    {
        switch (i) {
        case 0:
            return ("found 0");
        case 1:
            return ("found 1");
        }
        return ("Error");
    }
}

More specifically...

>> javac Test.java
>> java Test

test (0) = found 0
test (1) = found 1
test (0) = found 0
test (1) = found 1

Okay all is well, but then we try it with
optimizations.

>> javac -O Test.java
>> java Test

test (0) = Error
test (1) = found 0
test (0) = found 0
test (1) = found 0

Hmm, that doesn't look right.
Notice there is two problems.
The first result is wrong and
all of the rest return 0 which is the first case.

So we have three out of four incorrect.

Note: The results don't change if you return int
or anything else. It seems to have something to
do with argument passing and the stack.

-Paul Hill, ###@###.###
-Wade Rees, ###@###.###

(Review ID: 22047)
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