Question about mkfs.erofs and reproducible builds

[Gao Xiang]

On Wed, Oct 27, 2021 at 02:41:54PM +0300, Todor Ivanov wrote:
>     Hi, Gao,
> 
>     This is how I installed mkfs.erofs on debian10:
> 
> apt-get install pkg-config liblz4-dev gawk
> wget
> http://ftp.debian.org/debian/pool/main/e/erofs-utils/erofs-utils_1.3.orig.tar.gz
> tar xvzpf erofs-utils_1.3.orig.tar.gz
> cd erofs-utils-1.3/
> ./autogen.sh
> ./configure
> make
> make install
> 
> Can you tell me where do I clone it from and if build instructions are
> different?

You could get the latest dev branch from:
git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs-utils.git -b dev

We fixed some reproducable build issues recently, I think it might
be related to
https://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs-utils.git/commit/?id=6324fac820c28c6a946f595fa58a0abba0f48eb4

Thanks,
Gao Xiang

> 
> Kind regards,
> Todor
> 
> On Wed, Oct 27, 2021 at 2:27 PM Gao Xiang <hsiangkao at linux.alibaba.com>
> wrote:
> 
> > Hi Todor,
> >
> > On Wed, Oct 27, 2021 at 02:11:24PM +0300, Todor Ivanov wrote:
> > >         Hello,
> > >
> > >         We are trying to replace squashfs with erofs and face an issue
> > with
> > > reproducing the build from one and the same source folder. The source
> > > folder is "/etc" actually taken from an offline ubuntu 20.04 image and
> > > mounted as read-only.
> > >         I managed to narrow down the scope and it turns out that the
> > issue
> > > is when you have a file starting with "." (dot) in this folder. I.e.:
> > >
> > > etc/.anyfilename
> > >
> > > If I remove this file the erofs image of "etc" is reproducible (-T and -U
> > > are used as well)
> > >
> > > The issue is somehow related to the other 76 subfolders of etc and this
> > > file starting with dot. For example if I create such .anyfilename in usr
> > or
> > > var, there is no issue. Also if I create this file under
> > > etc/xdg/.anyfilename, this is fine as well.
> > > I also tried with etc from debian10 and the result is the same. Removing
> > > any file that starts with dot directly under etc, makes the erofs build
> > > reproducible.
> > > Do you have any advice on this?
> >
> > In principle filenames starting with '.' won't impact anything about
> > reproducible builds...
> >
> > Let me investigate it now... But may I ask which erofs-utils version
> > is used? Does it still happen on the latest dev branch?
> >
> > Thanks,
> > Gao Xiang
> >
> > >
> > > Regards,
> > > Todor
> >