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macOS has all its shells fail non-deterministically #1101

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opened 2026-01-14 14:25:22 +00:00 by raito · 1 comment
raito commented 2026-01-14 14:25:22 +00:00
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Since macOS Tahoe, we are seeing a heightened rate of spurious failures in our test suite, we had also a regular testsuite failure on one of our CI builder related to execution of programs without shebangs.

Those workloads are specifically unsafe forks (i.e. fork without execve).

Related:

This problem is not solved since cl/4910 reverted the fix as it breaks shell functionality for certain usual techniques to melt the shell rcfile inside the current shell. We do not know yet how to proceed.

Since macOS Tahoe, we are seeing a heightened rate of spurious failures in our test suite, we had also a regular testsuite failure on one of our CI builder related to execution of programs without shebangs. Those workloads are specifically [unsafe forks (i.e. fork without execve)](https://mikeash.com/pyblog/friday-qa-2012-01-20-fork-safety.html). Related: - https://zulip.lix.systems/#narrow/channel/7-Infra/topic/.60macos-builder02.60.20DISABLED/with/4579 - https://github.com/NixOS/nix/pull/14778 - https://gerrit.lix.systems/c/lix/+/4891 - https://gerrit.lix.systems/c/lix/+/4910 This problem is not solved since cl/4910 reverted the fix as it breaks shell functionality for certain usual techniques to melt the shell rcfile inside the current shell. We do not know yet how to proceed.
raito added this to the 2.94.1 milestone 2026-01-14 14:26:49 +00:00
raito modified the milestone from 2.94.1 to 2.96 2026-03-26 11:37:09 +00:00
raito commented 2026-03-26 11:37:35 +00:00
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A significant amount of mitigation have been merged but it remains that cl/4910 was reverted and we do not have good ideas at the time on how to fix this.

A significant amount of mitigation have been merged but it remains that cl/4910 was reverted and we do not have good ideas at the time on how to fix this.
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