dh: different dh option for -indep

[debian-devel@liska.ath.cx (Olе Streicher)]

Hi,

my package will create a separate arch-independent -doc package with
"sphinxdoc". Since therefore sphinx is not needed for architecure
dependent builds, I moved the build dependency of the package into the
Build-Depends-Indep field in debian/control:

---------------------8<------------------------
Build-Depends: debhelper (>= 9), [...]
Build-Depends-Indep: python-sphinx
---------------------8<------------------------

The file debian/rules, however, still has the main rule:

---------------------8<------------------------
%:
	dh  $@ --with autoreconf,sphinxdoc
---------------------8<------------------------

which fails when I try to build with the -B option with:

dh: unable to load addon sphinxdoc: Can't locate Debian/Debhelper/Sequence/sphinxdoc.pm [...]

What I tried is to create special targets for all arch dependent only builds:

---------------------8<------------------------
clean build-arch install-arch binary-arch:
	dh  $@ --with autoreconf
build-indep build install-indep install binary-indep binary:
	dh  $@ --with autoreconf,sphinxdoc
---------------------8<------------------------

However, this results in dh_autreconf called twice (?) which is
considered as an error. It also looks quite ugly to me. And, if the
sphinxdoc addon would have a special cleaning routine, this would not be
called on arch-indep builds.

What is the right solution here?

Best

Ole