[Buildroot] [PATCH v2 01/15] reproducibility: generate SOURCE_DATE_EPOCH

[Arnout Vandecappelle]

 In addition to Thomas's comments:

On 18-11-16 10:10, Jérôme Pouiller wrote:
> From: Gilles Chanteperdrix <gilles.chanteperdrix at xenomai.org>
> 
> When reproducibility is requested, generate a global SOURCE_DATE_EPOCH
> environment variable which contains either the date of Buildroot last
> commit if running from a git repository, or the latest release date.
> 
> This means that all packages embedding build dates will appear to
> have the same build date, so in case of new commit or release, all
> packages will appear to have been change, even though some of them
                                    changed


 Regards,
 Arnout

> may not have changed in fact.
> 
> The meaning of SOURCE_DATE_EPOCH is specified by the following
> specification:
>   https://reproducible-builds.org/specs/source-date-epoch/
> 
> Signed-off-by: Gilles Chanteperdrix <gilles.chanteperdrix at xenomai.org>
> Signed-off-by: Jérôme Pouiller <jezz at sysmic.org>
> ---
>  Makefile | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/Makefile b/Makefile
> index eff814b..17e49e4 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -249,6 +249,10 @@ ifeq ($(BR2_REPRODUCIBLE),y)
>  export TZ=UTC
>  export LANG=C
>  export LC_ALL=C
> +export SOURCE_DATE_EPOCH=$(SOURCE_DATE_EPOCH)
> +SOURCE_DATE_GIT = $(shell GIT_DIR=$(TOPDIR)/.git $(GIT) log -1 --format=%at)
> +SOURCE_DATE_CHANGES = $(shell date -d `echo $(BR2_VERSION) | sed 's/^\(....\)\.\(..\).*/\1-\2-01T23:59:59/'` +%s)
> +SOURCE_DATE_EPOCH = $(if $(wildcard $(TOPDIR)/.git),$(SOURCE_DATE_GIT),$(SOURCE_DATE_CHANGES))
>  endif
>  
>  # To put more focus on warnings, be less verbose as default
> 

-- 
Arnout Vandecappelle                          arnout at mind be
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Essensium/Mind                                http://www.mind.be
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