Failing tests related to t8code

[patrickersing]

In some CI runs I have observed failing tests that seem to be related to t8code . From the stack trace I can only see that it's due to segmentation fault, but not where it occurs.

The errors are only triggered in some of the runs and so far passed again after re-running.

The failing tests have been observed in multiple PRs in the following jobs and elixirs:

• t8code_part1 - t8code_2d_dgsem/elixir_euler_free_stream.jl
• t8code_part2 - t8code_3d_dgsem/elixir_euler_free_stream.jl
• mpi-macOS - t8code_3d_dgsem/elixir_euler_source_terms_nonconforming_unstructured_curved.jl
• mpi-ubuntu - t8code_2d_dgsem/elixir_euler_source_terms_nonconforming_unstructured_flag.jl
• threaded - windows - t8code_2d_dgsem\elixir_euler_source_terms_nonconforming_unstructured_flag.jl

I encountered this issue first two weeks ago in #1809 after merging these changes from main. However, since the error only occurs from time to time and disappeared after a re-run, it doesn't need to be related to these changes. From a quick look the oldest CI with problems that I found was from 3 weeks ago on 2024-01-22 here, so shortly after #1535 was merged.

[JoshuaLampert]

Thanks for the detailed report
cc @jmark

[jmark]

Thanks for the write-up! I'll take a look at this.