I've been building the package for some time so that I can install it on my machines. I use the standard command, dpkg-buildpackage -b -uc. Lately however when I build I get an error towards the end about LinuxCNC_Developer_es.pdf being missing, here's some of the log:
make[1]: Entering directory '/home/pi/linuxcnc-dev'
# The G-code quick reference html docs are built as
# `docs/html/en_US.UTF-8/gcode.html`. We install them
# into `/usr/share/doc/linuxcnc-uspace/` in each
# linuxcnc-doc-en_US.UTF-8 package, then rename them there (except
# for the English one) to include the language in the filename,
# so they don't collide when we install all the doc debs.
#
# Rename the "main" doc directories from
# `usr/share/doc/linuxcnc-uspace` to `usr/share/doc/linuxcnc`,
# because that's where the `.desktop` files look for the docs.
dh_installdocs --doc-main-package=linuxcnc-uspace --package=linuxcnc-doc-en
install -d debian/linuxcnc-doc-en/usr/share/doc/linuxcnc-doc-en
install -d debian/linuxcnc-doc-en/usr/share/doc/linuxcnc-uspace
cp --reflink=auto -a debian/tmp/usr/share/doc/linuxcnc/LinuxCNC_Developer.pdf debian/linuxcnc-doc-en/usr/share/doc/linuxcnc-uspace
cp --reflink=auto -a debian/tmp/usr/share/doc/linuxcnc/LinuxCNC_Documentation.pdf debian/linuxcnc-doc-en/usr/share/doc/linuxcnc-uspace
cp --reflink=auto -a debian/tmp/usr/share/doc/linuxcnc/LinuxCNC_Getting_Started.pdf debian/linuxcnc-doc-en/usr/share/doc/linuxcnc-uspace
cp --reflink=auto -a debian/tmp/usr/share/doc/linuxcnc/LinuxCNC_Integrator.pdf debian/linuxcnc-doc-en/usr/share/doc/linuxcnc-uspace
cp --reflink=auto -a debian/tmp/usr/share/doc/linuxcnc/LinuxCNC_Manual_Pages.pdf debian/linuxcnc-doc-en/usr/share/doc/linuxcnc-uspace
cp --reflink=auto -a debian/tmp/usr/share/doc/linuxcnc/AUTHORS debian/linuxcnc-doc-en/usr/share/doc/linuxcnc-uspace
cp --reflink=auto -a debian/tmp/usr/share/doc/linuxcnc/INSTALL.adoc debian/linuxcnc-doc-en/usr/share/doc/linuxcnc-uspace
cp --reflink=auto -a debian/tmp/usr/share/doc/linuxcnc/README.adoc debian/linuxcnc-doc-en/usr/share/doc/linuxcnc-uspace
cp --reflink=auto -a debian/tmp/usr/share/doc/linuxcnc/README.axis debian/linuxcnc-doc-en/usr/share/doc/linuxcnc-uspace
cp --reflink=auto -a debian/tmp/usr/share/doc/linuxcnc/axis_light_background debian/linuxcnc-doc-en/usr/share/doc/linuxcnc-uspace
cp --reflink=auto -a debian/tmp/usr/share/doc/linuxcnc/rtfaults.adoc debian/linuxcnc-doc-en/usr/share/doc/linuxcnc-uspace
cp --reflink=auto -a debian/tmp/usr/share/doc/linuxcnc/tklinuxcnc.adoc debian/linuxcnc-doc-en/usr/share/doc/linuxcnc-uspace
cp --reflink=auto -a ./docs/html/gcode.html debian/linuxcnc-doc-en/usr/share/doc/linuxcnc-uspace
chown -R 0:0 debian/linuxcnc-doc-en/usr/share/doc
chmod -R u\+rw,go=rX debian/linuxcnc-doc-en/usr/share/doc
install -p -m0644 debian/copyright debian/linuxcnc-doc-en/usr/share/doc/linuxcnc-doc-en/copyright
install -d debian/linuxcnc-doc-en/usr/share/doc-base/
install -p -m0644 debian/linuxcnc-doc-en.doc-base debian/linuxcnc-doc-en/usr/share/doc-base/linuxcnc-doc-en
mv debian/linuxcnc-doc-en/usr/share/doc/linuxcnc-uspace debian/linuxcnc-doc-en/usr/share/doc/linuxcnc
dh_installdocs --doc-main-package=linuxcnc-uspace --package=linuxcnc-doc-es
install -d debian/linuxcnc-doc-es/usr/share/doc/linuxcnc-doc-es
dh_installdocs: error: Cannot find (any matches for) "usr/share/doc/linuxcnc/LinuxCNC_Developer_es.pdf" (tried in ., debian/tmp)
make[1]: *** [debian/rules:112: override_dh_installdocs-indep] Error 255
make[1]: Leaving directory '/home/pi/linuxcnc-dev'
make: *** [debian/rules:38: binary] Error 2
dpkg-buildpackage: error: fakeroot debian/rules binary subprocess returned exit status 2
