Re: update on reproducible builds

[christos%zoulas.com@localhost (Christos Zoulas)]

On Dec 19,  3:29pm, martin%duskware.de@localhost (Martin Husemann) wrote:
-- Subject: Re: update on reproducible builds

| On Mon, Dec 19, 2016 at 09:24:00AM -0500, Christos Zoulas wrote:
| > Because we want keep the checksums of all the files identical. Since some
| > files (like tar files or random archives contain timestamps, this is impossible
| > without choosing a particular timestamp).
| 
| Yes, I understand, but I disagree with that idea. Who cares about tar files
| and why? Lazyness or strange manifestos are no good reason to complicate
| the build system and use bogus timestamps.

It is not just tar archives, it is ar archives too. It is other places where
timestamps are stored. The timestamps are not bogus. You just have a magic
system that can build things instantly and atomically after the last commit.
We care about easily being able to test: is this release the same as that?

| > This is the time the build cluster started a checkout, not the time of
| > the last checkin.
| 
| Yes, and it is well documented and easy to reproduce. Why do any more
| magic?

Because it is neither atomic nor reliable or reproducible (i.e. the tree
is not locked during checkout so it will not catch commits happening during
that window -- or it will depending if it passed them or not)?

christos