I have simplified the License for the “jo” package from “GPLv2+ and MIT and Public Domain” to the effective license “GPLv2+”. A spec file comment explains:
# The entire source is GPLv2+, except json.c and json.h, which are MIT, # and base64.c and base64.h, which are Public Domain. Since these files # are only used as sources for an executable with an effective license # of GPLv2+, the overall package license remains GPLv2+.
The MIT-licensed files json.* are a slightly forked version of the copylib ccan-json, and are properly handled under the bundling guidelines. The public-domain files base64.* look like a copylib too, but I was never able to identify anywhere from which it might have been copied.