Mark H Weaver <m...@netris.org> skribis: > Mark H Weaver <m...@netris.org> writes: > >> Mark H Weaver <m...@netris.org> writes: >> >>> However, this raises a deeper problem: all of the outputs of >>> 'patch-and-repack' contain non-deterministic timestamps, and these >>> timestamps can cause problems with future builds. >>> >>> Would it be sufficient to simply zero out all of the timestamps before >>> repacking? >> >> I looked into this a bit more. In addition to timestamps, the other >> impure bits getting into tar files are the names and numeric ids of the >> owner and groups. Section 4.3.1 (Overriding File Metadata) of the GNU >> tar manual describes how to override these when creating an archive. >> >> My guess is that the following options would be sufficient to make the >> generated tar archives deterministic: >> >> --mtime=@0 --owner=root:0 --group=root:0 > > This seems to work well, so I've added these flags when creating > tarballs in commits 2e9511dfbdb5ddd78c2f205c4ca7fc23738d79f8 and > c09e6a5f5e2a77beff89d68069f3037c1b6310e5 in core-updates.
That sounds like the right thing (it’s also what is used in gnu/system/install.scm for the binary tarball.) Thanks for noticing and fixing it! Ludo’.
