ply: Make generated lextab.py deterministic #531
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Set ordering is non-deterministic, and thus, this serializes the generated _lextokens in random order. Adding a sorted(...) here fixes that. Keeping the generated code deterministic comes with benefits: for hermetic build systems like Bazel which check the hashes of inputs/outputs, we can know when we don't need to rebuild code that depends on pycparser, and get better cache hits. Note that _lextokens does not exist in upstream ply, so I patched it here directly. If/when pycparser uprevs to a newer ply, this won't matter anymore.
eliben
approved these changes
Mar 30, 2024
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Set ordering is non-deterministic, and thus, this serializes the generated _lextokens in random order. Adding a sorted(...) here fixes that.
Keeping the generated code deterministic comes with benefits: for hermetic build systems like Bazel which check the hashes of inputs/outputs, we can know when we don't need to rebuild code that depends on pycparser, and get better cache hits.
Note that _lextokens does not exist in upstream ply, so I patched it here directly. If/when pycparser uprevs to a newer ply, this won't matter anymore.