Bug#762105: lintian: package-contains-timestamped-gzip incorrectly complains about files from the upstream tarball

[Stuart Prescott <stuart@debian.org>]

Package: lintian
Version: 2.5.27
Severity: normal

Dear Maintainer,

The package-contains-timestamped-gzip tag complains about gzipped files
that are in the upstream tarball. While it is true that these files were
compressed and contain a timestamp, it is not true that this timestamp will
be different each time the package is built, which is what the tag description
claims:

N:   The package contains a gzip-compressed file that has timestamps. Such
N:   files make the packages unreproducible, because their contents depend
N:   on the time when the package was built.

My experience is that it's not uncommon for test data sets in particular to
be gzipped inside the upstream tarball. A package that triggers tag this is
pyxplot.

It would be best if lintian didn't complain about compressed files that are
also present in the upstream package. If lintian's architecture can't cope
with this, then downgrading the certainty of this tag and perhaps telling the
maintainer to override it if it is a false-positive would be appropriate.

cheers
Stuart