Please consider merging branch hothasktags of my repo https://git.spwhitton.name/propellor
Moves the 2>/dev/null redirection in the Makefile rule for tags in order to silence xargs if hothasktags is not installed (avoids xargs: hothasktags: No such file or directory).
I assume that your originally intention was not to cause an error if hothasktags is not installed, since you have || true at the end of the line. However, someone trying to build propellor's Debian package saw the error output from xargs and thought it meant hothasktags should be a build-dep. This patch prevents someone thinking that.
-- spwhitton