Re: [Bug-XBoard] xboard: Error: second chess program exited unexpectedly

[h.g. muller]

At 18:21 31-10-2009 +0200, matrix one wrote:
> Hi,
>
> Is happend only with toga2
>
>
>
> Linux s3 2.6.31-14-generic #48-Ubuntu SMP Fri Oct 16 14:05:01 UTC 2009 
> x86_64 GNU/Linux
>
> xboard -debug -size huge -coords -scp 'polyglot 
> /home/matrix/.polyglot/toga2.ini' -fcp 'polyglot 
> /home/matrix/.polyglot/stockfish.ini'
> StartChildProcess (dir=".") polyglot /home/matrix/.polyglot/stockfish.ini
> StartChildProcess (dir=".") polyglot /home/matrix/.polyglot/toga2.ini
> Warning: XtRemoveGrab asked to remove a widget not on the list
> xboard: Error: second chess program (polyglot 
> /home/matrix/.polyglot/toga2.ini) exited unexpectedly
> *** glibc detected *** xboard: double free or corruption (out): 
> 0x00007fff12a1af40 ***

Hmm, the RemoveGrab warning makes it a bit suspect. I could find only one 
call to XtRemoveGrab()
in the entire source, and this is in ThawUI(). Apparently XBoard uses the 
kludge to let a deaf-and-dumb
widget (the messageWidget) grab focus while waiting for the engine to 
complete initialization.

I am not sure if we are dealing here with a bug in the error exit procedure 
triggered by toga2 crashing,
or that something is badly wrong in XBoard that makes it unjustly believe 
toga2 exits. I suspect
the former, as that would explain why this only happens with toga2, and not 
with other engines.
Is this a reproducible error? If so, it would help to see the Polyglot log 
file (which can be obtained
by setting PolyglotLog=true in the toga2.ini file), which mght indicate if 
the trouble starts there.

H.G.