This might be the result of a fileIn (possibly one of the 
LanguageEnvironment tests). You can try two things:
1) Check your recent changes if anything got logged. A fileIn from 
loading a project file or so should be logged.
2) Insert a "self halt" into the method (before the fork) to see where 
it comes from.

Cheers,
   - Andreas

On 1/8/2011 11:47 AM, Bernhard Pieber wrote:
> Dear Squeakers,
>
> I did the following:
> 1. I opened the latest trunk image Squeak4.2-10779-alpha.image with the Mac OS X VM Squeak 5.8b12.
> 2. Update Squeak.
> 3. Run all tests. After all the tests I get a debugger with "Error: Instances of StrikeFont are not indexable"
>
> --- The full stack ---
> StrikeFont(Object)>>error:
> StrikeFont(Object)>>errorNotIndexable
> StrikeFont(Object)>>size
> StrikeFont(Object)>>basicAt:put:
> StrikeFont(Object)>>instVarAt:put:
> StrikeFont(Object)>>readDataFrom:size:
> ReferenceStream(DataStream)>>readInstance
> ReferenceStream(DataStream)>>next
> ReferenceStream>>next
> ReferenceStream(DataStream)>>readArray
> ReferenceStream(DataStream)>>next
> ReferenceStream>>next
> [] in StrikeFontSet class>>installExternalFontOn:encoding:encodingName:textStyleName:
> [] in [] in MultiByteBinaryOrTextStream(PositionableStream)>>untilEndWithFork:displayingProgress:
> BlockClosure>>ensure:
> [] in MultiByteBinaryOrTextStream(PositionableStream)>>untilEndWithFork:displayingProgress:
> [] in BlockClosure>>newProcess
>
> Is there a way find out where this process is created? Tracing senders of StrikeFontSet class>>installExternalFontOn:encoding:encodingName:textStyleName: leads ultimately to no senders. In a Process Browser I do not see anything unusual.
>
> Cheers,
> Bernhard
>