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Crash when instantiating a Model class

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#385 2 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
25/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
python
Domain
tooling

Research direction

Reproduce the minimal Model() example on Windows 10 with Python 3.12.0, python-mip 1.14.2, and Spyder, then trace the Model initialization path to identify where the access violation occurs. Done means creating a Model with no parameters completes without a fatal exception, with a regression test covering the reported case.

Written by the indexing model from the issue text.

Description

Describe the bug
I've just installed python-mip and instantiating a Model class with no parameter causes a crash.

To Reproduce
Executing this code:

from mip import Model

m = Model()

produces this error and triggers a python kernel restart:

Windows fatal exception: access violation

Expected behavior
Instantiating a Model class should not produce any error.

Desktop (please complete the following information):

  • Operating System, version: Windows 10, version 22H2
  • Python version: 3.12.0
  • Python-MIP version (we recommend you to test with the latest version): 1.14.2

Additional context
Executed within a Spyder IDE.

Dominant language
Linear Programming
Stars
601
Forks
108
PR merge metrics
No merged PRs in 30d

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