Justification: Policy 4.5
Your packages contains an embedded code copy of texi2html which is
copyright Lionel Cons and others and is licensed under the GPL and
Creative Commons Attribution-ShareAlike license. This information is
missing from debian/copyright of gperf and is thus a violation of policy
I found this bug while working on the reproducible builds project  to
make texi2html produce reproducible output.
>From that point of view there are two options:
1. remove the embedded code copy  and build-depend on texi2html
(this would also make policy §4.13 happy). I would prefer this
solution and would supply you with a patch if you want. Your package
would then automatically become reproducible.
2. keep the embedded code copy and amend your debian/copyright. In this
case I would open another bug so that your embedded copy of
texi2html is patched to produce reproducible output.
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