Comment (by Eloisa Bentivegna):

Thanks @Roland Haas , interesting I didn’t realize this earlier… I agree to revert the single-thread commit, and try getting some agreement with a more recent gcc. Also, the test obviously involves data which is very affected by roundoff, and this simply shouldn’t be the case. We have had recurring problems with this as any perturbation of any origin ends up showing up there. Perhaps it’s a matter of turning this into a more sensible test in the first place.

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Ticket URL: https://bitbucket.org/einsteintoolkit/tickets/issues/2289/ct_multilevel-tests-abort-when-run-using