Re: Passing tar(1) options via git-archive(1)

> Some background from the git-archive(1) man page:
> 
>     git-archive behaves differently when given a tree ID versus when
>     given a commit ID or tag ID.  In the first case the current time is
>     used as the modification time of each file in the archive.  In the
>     latter case the commit time as recorded in the referenced commit
>     object is used instead.
> 
> Would it make sense to add an --mtime option to git-archive(1) to enable
> explicitly setting the mtime for all files in the archive?  It could
> just pass through to the tar(1) --mtime option.
> 
> My use case is `git archive HEAD | docker build -`, in which the Docker
> cache is prevented from working because the mtime keeps getting bumped
> on all files.  I would like to have the mtime always be the same.
> 
> See, e.g., <https://github.com/deis/deis/issues/1334>.
> 
> Otherwise, how about a generic way to pass options to tar(1)?