Re: Optimizer optimizing away too much?

[Bryce McKinlay <mckinlay at redhat dot com>]

Could you post a full test case please? That behaviour would surprise 
me, too.

Thanks

Bryce

Thomas Aeby wrote:

> Hello
>
> Great oops for me: I just found out, that GCJ (3.4.0), using
> with "-O" optimizes away something like
>
>    ...
>    public synchronized void increment() {
>        value++;
>    }
>
> I assume the optimizer thinks "value++" is just an unused value
> and does not respect that this also changes the value of value.
>
> If I add a System.out after value++ like
>
>   public ...
>   {
> 	value++;
> 	System.out( "value of value: " + value );
>   }
>
> or change value++ into value = value + 1 everything wroks well.
>
> I was kind of surprised :-)
>
> Am I expecting something totally silly, shouldn't one ever use
> optimization? What is your experience with GCJ and optimization?
>
> Best regards,
> Tom
>