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gzip.compress output is non-deterministic #125260
Description
Bug report
Bug description:
import gzip
gzip.compress(b'')output varies by default, which breaks reproducible builds in cases such as
https://github.com/getmoto/moto/blob/fc60bd1c5f6e6184e30a6db8b65059a2855cd28e/setup.py#L28
GNU gzip (since 1.10) defaults to a zero timestamp for compressing stdin. And after year 2106, no mtime could be stored anyway.
CPython versions tested on:
3.13
Operating systems tested on:
Linux
Activity
pythongh-125260: gzip: let compress mtime default to 0
pythongh-125260: gzip: let compress mtime default to 0
ZeroIntensity commentedon Oct 10, 2024
Per @AA-Turner, I'm marking this as a feature.
pythongh-125260: gzip: let compress mtime default to 0
pythongh-125260: gzip: let compress mtime default to 0
pythongh-125260: gzip: let compress mtime default to 0
gh-125260: Change the default ``gzip.compress()`` mtime to 0 (#125261)
thesamesam commentedon Oct 14, 2024
See also #112346 for the OS field.
Rogdham commentedon May 10, 2025
Should the same change be made in the default for
mtimeparameter inGzipFile.__init__? @bmwiedemann @AA-Turner