Some time ago my package linuxinfo aquired a bug (#1047898) whereas
dpkg-buildpackage ; dpkg-buildpackage -S
does not work. And if fact, it does not.

The reporter informed me that this is a potential violation of Debian
Policy section 4.9 (clean target), but that this was under discussion
at the time of the reporting.

I first checked (my) upstream build system. Except for one stamp file
(which is *much* less than done by debhelper) the build is idempotent,
i.e.:

./configure && make && make clean

returns the sources into the state as shipped.

In the past I had an explicit debian/rules, but to ensure compliance
with the ever evolving Debian Policy I made it on purpose very simple:

include /usr/share/dpkg/architecture.mk

ifeq ($(DEB_HOST_ARCH),amd64)
        confflags += --with-pcre
else ifeq ($(DEB_HOST_ARCH),i386)
        confflags += --with-pcre
else ifeq ($(DEB_HOST_ARCH),x32)
        confflags += --with-pcre
endif

%:
        dh $@

override_dh_auto_configure:
                dh_auto_configure -- $(confflags)

As you can see, I only add (architecture dependend) configuration flags
for linking with pcre.

dh seems to delete quite a few files shipped in the package.

For me, this is a clear bug in dh, as linuxinfo just uses it plain and
there is no "manipulation" of build files happening (on purpose).

I checked dh_clean(1) and dh(1), but could not find any mention of how
to modify this (which I would not have expected anyhow).

If the severity of 1047898 is changed, then I will change this one (as
it is the root cause). In linuxinfo I probably could work around this,
by backing up all affected files before clean and restoring them after
clean (using an override). But this is a band aid, not a solution.