Re: [Help-glpk] Error detected in file glplib10.c at line 109

[Andrew Makhorin]

>     I am trying to parallelise the Qt/C++ code of  multi agent model
> representing farmers.
> For the time being I #39;m using only 1 thread as I got from this
> list that glpk is, at the present time, not  re-entrant.
> The funny(!) side is that when I use the new code (see down), even
> if it use only **1** working threads, the unpatched version of glpk
> crash.
> I used then the doc example and I was able to receive the following error 
> message when crashing:
> Assertion failed: xlcmp(env->t_last, t) <= 0
> Error detected in file glplib10.c at line 109

> Is it a glpk bug or something I am doing seriously very wrong ??

I don't think it is a glpk bug. Something unpredictable occured,
because original glpk code is not re-enterable.

You can make glpk re-enterable by replacing src/glplib02.c with a
re-enterable version (for details see comments). However, glpk has
no synchronization features, so the same problem object must not be
used in different threads.