Make rust build deterministic #1213
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Hey @bmwiedemann thanks for the PR!
Could you help me understand why not? How can I reproduce this nondeterminism? |
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I just did two clean builds as similar as possible. Same CPU, same username, same path, same timezone, locale, umask, date... and it still differed in the https://rb.zq1.de/compare.factory-20240904/diffs/python-libcst-compare.out shows a (partially filtered) diff. |
See https://reproducible-builds.org/ for why this is good.
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hmm. For some reason the variations are gone now with rust-1.81.0 |
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There are still variations - they just don't appear every time. |
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Summary
We disable LTO and use
codegen-units = 1for deterministic build results of the rust code.See https://reproducible-builds.org/ for why this is good.
rust-lang/rust#128675 states that the default
codegen-units = 16should be deterministic, but here it clearly is not.Test Plan