+.SH FILES IN THE SOURCE PACKAGE BUT NOT IN GIT - DOCS, BINARIES ETC.
+Some upstream tarballs contain build artifacts which upstream expects
+some users not to want to rebuild (or indeed to find hard to rebuild),
+but which in Debian we always rebuild.
+.LP
+Examples sometimes include crossbuild firmware binaries and
+documentation.
+To avoid problems when building updated source
+packages
+(in particular, to avoid trying to represent as changes in
+the source package uninteresting or perhaps unrepresentable changes
+to such files)
+many maintainers arrange for the package clean target
+to delete these files.
+.LP
+dpkg-source does not
+(with any of the commonly used source formats)
+represent deletion of files (outside debian/) present in upstream.
+Thus deleting such files in a dpkg-source working tree does not
+actually result in them being deleted from the source package.
+Thus
+deleting the files in rules clean sweeps this problem under the rug.
+.LP
+However, git does always properly record file deletion.
+Since dgit's
+principle is that the dgit git tree is the same of dpkg-source -x,
+that means that a dgit-compatible git tree always contains these
+files.
+.LP
+For the non-maintainer,
+this can be observed in the following suboptimal occurrences:
+.TP
+\(bu
+The package clean target often deletes these files, making the git
+tree dirty trying to build the source package, etc.
+This can be fixed
+by using
+.BR "dgit -wg" " aka " "--clean=git" ,
+so that the package clean target is never run.
+.TP
+\(bu
+The package build modifies these files, so that builds make the git
+tree dirty.
+This can be worked around by using `git reset --hard'
+after each build
+(or at least before each commit or push).
+.LP
+From the maintainer's point of view,
+the main consequence is that to make a dgit-compatible git branch
+it is necessary to commit these files to git.
+The maintainer has a few additional options for mitigation:
+for example,
+it may be possible for the rules file to arrange to do the
+build in a temporary area, which avoids updating the troublesome
+files;
+they can then be left in the git tree without seeing trouble.