[U-Boot] [Reproducible-builds] [PATCH] build: create time and date independent binary

[Heiko Schocher]

Hello Vagrant,

Am 19.07.2015 um 15:14 schrieb Vagrant Cascadian:
> On 2015-07-19, Holger Levsen wrote:
>>>> All this said, if you send me patches, I will probably deploy them as I'm
>>>> very curious and more reproducibility efforts are good :-) We can can
>>>> always decide to remove or move them later.
>>>
>>> I wish to make all contributions upstream. What would really help at
>>> first would be to have all targets built regularly to see where work is
>>> needed. This is where I think the Debian infrastructure could help, in a
>>> similar way as what was started for Coreboot.
>
> FWIW, I was planning on including this patch to u-boot in the next
> upload to Debian:
>
>    https://anonscm.debian.org/cgit/collab-maint/u-boot.git/tree/debian/patches/use-date-from-debian-changelog.patch?h=experimental-2015.07
>
> I *think* that actually makes u-boot build reproducibly with Debian's
> reproducible builds toolchain when SOURCE_DATE_EPOCH is set, but I
> haven't tested it fully. I might have missed some other sources of
> non-determinism...
>
>
> Hoping to get some armhf buildd nodes up an running soonish... although
> it should also be buildable with the cross-toolchains, if the
> reproducible buildds coulld be made to support that.

Did you see my v2 patch [1] for u-boot?

It also builds now u-boot images created with mkimage reproducible ...

If I interpret your patch from above correct, you add with
SOURCE_DATE_EPOCH a specific fix timestamp?

I think, this could be included to my approach too ...

If SOURCE_DATE_EPOCH is defined, use it, fi not defined
define U_BOOT_DATE, U_BOOT_TIME and U_BOOT_TZ
with my default settings from [1] ...

All only if CONFIG_SYS_EXACT_BINARY is set in the u-boot
config of course ...

What do you think?

bye,
Heiko
[1] http://patchwork.ozlabs.org/patch/487530/
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