Andrew,

--nopresol option affects only lp, not mip.


Actually, if --nointopt is specified, then the glp_simplex() call in
glpsol.c will use the lp presolver parameters, so --nopresol is also needed
to completely disable presolving.


> > Also "glpsol --lp --nointopt problem.lp" works which points to the MIP
> > presolver as the "faulty" part.
>
> Yes, glpsol fails on your instance because of the mip preprocessor.


In this case, the mip preprocessor does not look like it is doing a lot
more than the lp one. The difference is due to the additional power of 2
scaling done in this case (together with the preprocessing changes of
course).

Hopefully, this observation will help you isolate the issue.

Best Regards,

Chris Matrakidis
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