Endless loops in computation code (1.6.0_22).

Dawid Weiss dawid.weiss at gmail.com
Thu Mar 3 23:44:14 PST 2011

> After watching maven download jars for 10 minutes, it actually ran the test
> and reproduced it.

Ehm, I'm not a big fan of Maven myself, but trying to get used to what
people use (and many people do use maven -- perhaps they need those 10
minutes to grab a coffee in the morning, don't know).

>  I put together a little main to run the test manually and just reproduced
> it with -XX:+PrintCompilation.  It hung right after it printed this:
>  3%      org.jsuffixarrays.DivSufSort::sortTypeBstar @ 979 (1125 bytes)

Ok, so it must be Maven's test plugin messing with the stdout/stderr log
order then. I'm glad you could reproduce it.

> so it's possible it's a bug with with on stack replacement.  I've
> reproduced it with the latest 1.7 as well so it's something we haven't seen
> before.  I filed 7024475 for this and put you on the interest list.  I can't
> reproduce it in 6u12 but I can in 6u14 so I think it appeared there.

Great, thanks. I fiddled with that code a little bit moving loop counter
increments here and there, but it seems to be fairly resilient to where they
are (as long as the logic doesn't change). Interestingly, moving the sysout
does seem to fix things (if you move it after the if in the inside loop).

I appreciate your help, Tom. This is truly fascinating stuff.
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