Missing changelog file

[Rock Storm <rockstorm@gmx.com>]

Dear debian-legal,

I would like to package a program into Debian that is distributed under
a GPL-3 license but currently has no changelog file. Upstream does not
deliver this or any other similar file with the latest release and I’ve
been told that this is a requirement for software licensed under this
kind of license.

Since the upstream development is done using “git” it has been
suggested to include the output of “git log” as the changelog.
Nonetheless, this output will surely be quite long because it contains
hundreds of commits, and some of them will most likely be poorly
documented.

Is the existence of an upstream changelog file mandatory in order to
distribute this software under the GPL-3? Will it be compliant with the
DFSG to incorporate this software into Debian without an upstream
changelog file? If not, will the “git log” output suffice as a
changelog file thus making the package compliant with the DFSG?

Thanks a lot,
Regards,
Alvaro