Re: [v2 0/1] Erlang

[Leo Famulari <leo@famulari.name>]

On Fri, Apr 01, 2016 at 10:19:11AM +0200, Pjotr Prins wrote:
> 
> On Thu, Mar 31, 2016 at 03:35:44PM -0400, Leo Famulari wrote:
> > This adds Erlang.
> > 
> > Originally written by Steve Sprang, I added the man pages and fixed all
> > the "FHS bugs" I noticed.
> > 
> > Pjotr used it to build a working Elixir:
> > http://lists.gnu.org/archive/html/guix-devel/2016-03/msg00999.html
> 
> Better even, I am actually using that Elixir and Erlang :). Please
> push when there are no other issues.
 
Cool! From my point of view, there are no blocking issues.

There are two sources of non-determinism when building repeatedly on the
same machine.

All the .beam files have timestamps and build paths embedded [0]. This
is a known issue without a clear solution. The build paths don't seem so
bad to me, since my understanding is that they are set deterministically
by the Guix builder.

There are also some .script files that also embed timestamps in a human
readable string. Grepping for the string makes it easy to find the
source of this. We could patch the timestamp format string with the
value of SOURCE_DATE_EPOCH.

Thoughts?

[0]
https://wiki.debian.org/ReproducibleBuilds/TimestampsInBeamFiles