Thanks for the report, Florian.

I figure that systemic solution for clufter would rather be
https://src.fedoraproject.org/rpms/python-rpm-macros/pull-request/3

Indeed, I can provide a temporary workaround till the change
like above lands in Fedora.

What do you think?

I didn't realize that ccs_flatten was built by the Python extension build process.  In this case, it can wait until we have a more general solution for that.

Should have revealed that directly, sorry.

In fact, it's slightly more complicated, since for obvious reasons,
distutils slash setup.py arrangement is only extension-as-in-shared-lib
ready, so some tweaking/monkey-patching in setup.py was needed to make
standalone executable built along the same lines (which obviated
dependencies on other build systems and made the clufter self-contained
for native Python source redistribution).  Nonetheless, figuring out
the correct flags is solely in the hands of distutils, which in turn
will honour respective environment variables, hence the handover.

This bug appears to have been reported against 'rawhide' during the Fedora 28 development cycle.
Changing version to '28'.

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