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Non-deterministic segfault of tests with Z3 in Travis

See original GitHub issue

I noted that the builds having the z3 solver can non-deterministically yield a segfault on Travis.

I tried to reproduce the problem locally even using the docker Travis image with no luck.

We could try two different strategies here:

Update Z3 to a newer nightly build and see if the problem goes away
Try to update the libstdc++ of the travis image (it is more a feeling than a suspect, but in my local experiment with the quay.io/travisci/travis-python docker image I had to update this to make Z3 work at all)

Issue Analytics

State:
Created 6 years ago
Comments:22 (16 by maintainers)

Top GitHub Comments

1reaction

mikandcommented, May 20, 2022

@marcogario Just to clarify: the issue is now fixed on the pysmt side with the workaround in #713. @Hook25 (many thanks!) posted the issue upstream, if/when Z3 fixes the issue we can get rid of the workaround.

1reaction

mikandcommented, Mar 20, 2019

I think I finally isolated the issue! On #564 I disabled the test test_tactics_z3 in test_solving.py and since then I got no more segfault errors. This smells of victory because the test actually accesses the internal Z3 nodes and applies a custom tactic, so it may very well mess up the ref/deref system.

I still have no clear explanation/fix of the problem, but I’ll have a look asap.

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