Bug#833707: libtasn1-6 FTCBFS: runs help2man on host architecture binaries

[Helmut Grohne]

Hi Andreas,

On Fri, Aug 12, 2016 at 07:10:23PM +0200, Andreas Metzler wrote:
> How about doing a simple
> 
> # cross-compiling
> if [ `dpkg-architecture -q DEB_BUILD_GNU_TYPE` != `dpkg-architecture -q DEB_HOST_GNU_TYPE` ] ; then \
>         touch `grep -l help2man doc/*.[1-8]` ; \
> fi

I generally prefer a builds-from-source experience over a
reuse-precompiled-stuff experience. For that reason, my proposed patch
actually runs help2man.

> in debian/rules's override_dh_auto_configure instead? Just looking at
> the results it has the same problem as the
> use-system-libtasn1-bin-approach, the shipped manpage does not
> necessarily match the built binaries. However it is not worse but
> guarantees that the upstream version matches.

I was trying to add the ability to say "Build-Depends: something (=
${source:Version})" to dpkg without success. Technically, the versions
can indeed mismatch. In a typical cross build scenario, they will always
match.

> Also this would be zero-maintainance instead of carrying a patch.
> Would this be an acceptable solution for the problem?

Your approach certainly works for me.

The preference stated above is a mild one and there are quite a few ways
to address help2man issues. We saw only two thus far. Others include:
 * Dropping manual pages in a <nodoc> profile.
 * Splitting manual pages into an arch:all package.

Given that I wanted to provide a patch, I had to choose one. There
doesn't seem to be a universally best solution to this issue.

Bonus points if native builds validate that the help2man output matches
the shipped copies to ensure cross vs. native reproducibility. ;)

Helmut