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SCIP - Solving Constraint Integer Programs
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System.AccessViolationException when trying to delete a restriction after LPError #88

Open Thiago-NovaesB opened 3 months ago

Thiago-NovaesB commented 3 months ago

When creating an LP problem where there are NaN in the matrix, I got an LPError when trying to optimize, which makes sense. However, when trying to delete restrictions from the problem, I get the System.AccessViolationException error. It seems to me that there is a problem in SCIP's memory management, which causes it to have problems with references after an LPError in certain cases.

Is this a known issue? I can share the .lp if not.

svigerske commented 3 months ago

It could be that SCIP is left in a bad state when there is a serious error like this (i.e., SCIPsolve() not returning with SCIP_OKAY) and usually programs then terminate or, at most, free the SCIP instance, but do not try to modify and continue.

In order to look into it, a way to reproduce this could indeed be helpful.