[Buildroot] [PATCH 09/34] reproducibility/libglib2: allow removing codegen

[Arnout Vandecappelle]

On 05/08/16 22:25, Gilles Chanteperdrix wrote:
> On Sat, May 07, 2016 at 11:04:25PM +0200, Arnout Vandecappelle wrote:
>> On 04/30/16 09:49, Gilles Chanteperdrix wrote:
>>> But this is not sufficient, compiling the python bytecode with the
>>> same interpreter in different environments yields different binaries,
>>
>>   Er, this is worrisome... You are saying that we don't have a chance in hell of
>> generating reproducible python bytecode?
>
> I am not a python specialist, but it seems to me four bytes in the
> python generated bytecode are the build timestamp, so unless there
> is a way to override it with SOURCE_DATE_EPOCH, I do not see that
> possible.

  I've checked the docs. What is saved is the timestamp of the .py file, not the 
build time.

  I think it would make sense to run 'touch -d @$(SOURCE_DATE_EPOCH)' on all 
files after patching to capture this aspect. This was also proposed for 
Fedora[1] (though there it was only for the .py files). Not sure what happened 
with that proposal in the end.

  Regards,
  Arnout

[1] https://lists.fedoraproject.org/pipermail/python-devel/2014-August/000617.html



-- 
Arnout Vandecappelle                          arnout at mind be
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