SqueakSource: Restarted, but with Problems

Ned Konz ned at squeakland.org
Thu Dec 2 22:25:20 UTC 2004


On Thursday 02 December 2004 1:17 pm, Adrian Lienhard wrote:
> When I looked at the image today, it was still running but didn't react
> anymore. And there were some open "Syntax Error" windows which I don't
> understand. Can somebody explain to me how there can be syntax errors
> during normal use? I mean, there was no code compiled... Actually I
> have seen those syntax errors recently on another server. Both are 3.7
> images. I've put a screen shot of those errors at:
> http://www.adrian-lienhard.ch/files/syntaxerrors.pdf, though I don't
> know if this helps much. Note also, the Transcript showing all those
> undeclared bits of code.
>
> Anybody an idea what went wrong here?

I'd say that what happened is that your sources file got damaged somehow 
(truncated, replaced, whatever) and then there was an exception.

During the course of logging the exception, the stack was dumped; to do this, 
we had to get the source. Which was out of sync with the pointers in the 
CompiledMethods.

Now, this would not have been a big problem except for one of two things:

* If a debugger is opened, it tries to get the byte range corresponding to the 
active pc in the active stack frame. To do this, it compiles the source code 
(or decompiles the method if it has to, but it believed that it had the 
source code in this case).

* If you have pretty print turned on (I'm not sure if this preference is used 
for the debug logs), we again call the compiler when we print code.

-- 
Ned Konz
http://bike-nomad.com/squeak/



More information about the Squeak-dev mailing list