[Buildroot] [PATCH 1/1] fs/common.mk: enable multithreaded xz compression

[Peter Korsgaard <peter@korsgaard.com>]

>>>>> "Thomas" == Thomas Petazzoni <thomas.petazzoni@bootlin.com> writes:

 > On Sun, 27 Jan 2019 23:06:14 +0100
 > Peter Korsgaard <peter@korsgaard.com> wrote:

 >> > Does it matter than the output of -T 0 and -T 1 are identical ?  
 >> 
 >> It would cause an extra change in output between buildroot versions
 >> using -T 0 and ones using -T 1 - But OK, probably that isn't really
 >> important given all the other changes.

 > Well, BR2_REPRODUCIBLE is definitely not about guaranteeing identical
 > output between Buildroot versions. How could this even work, since we
 > are bumping the version of dozens/hundreds of packages ?

 > BR2_REPRODUCIBLE is about given a fixed Buildroot version and
 > configuration, be able to generate a binary-identical result.

Correct, hence my note "isn't really important".


 >> > What matters for BR2_REPRODUCIBLE=y is if the same input, with -T 0,
 >> > always provide the exact identical output.  
 >> 
 >> With the new patch that only enables -T 1 for !reproducible builds,
 >> that is correct.

 > I thought -T 0 was the problematic thing as it enabled automatic
 > parallelization, while -T 1 explicitly disabled parallelization.

Sorry, I got T 0/1 mixed up in my mail, like I explained in the
followup.

-- 
Bye, Peter Korsgaard