I spoke with the koji admins. They had this to say:

<jwb> dgilmore, rel-eng ticket 1375 looks weird
<jwb> mbonnet, ^
<mbonnet> jwb: url?
<jwb> https://fedorahosted.org/rel-eng/ticket/1375
<jwb> mbonnet, builds failed with 'file truncated'?
<mbonnet> jwb: looks like a make -j problem
<jwb> mbonnet, possibly, yeah
<mbonnet> jwb: I bet they haven't setup their Makefile dependencies correctly, so it's calling the linker before compilation is done

Gah. Horrible formatting. Let's try again:

{{{
<jwb> dgilmore, rel-eng ticket 1375 looks weird
<jwb> mbonnet, ^
<mbonnet> jwb: url?
<jwb> https://fedorahosted.org/rel-eng/ticket/1375
<jwb> mbonnet, builds failed with 'file truncated'?
<mbonnet> jwb: looks like a make -j problem
<jwb> mbonnet, possibly, yeah
<mbonnet> jwb: I bet they haven't setup their Makefile dependencies correctly, so it's calling the linker before compilation is done
}}}

Thanks; I'll look into testing this in mock w/ a higher -j option to see if I can replicate the problem locally.

My local builds are running w/ make -j4 and I can't reproduce the error (at least, not like I can on koji). Some builds that fail are -j8, but this one was -j4 as well:

http://koji.fedoraproject.org/koji/getfile?taskID=1247396&name=build.log

Sorry to ping again on this, but I can't reproduce this locally (w/ -j4, -j8, or -j12) and the devs for gpsd don't have an idea about what might be going on here. I've tried building gpsd on F-9 through F-11 and all have the same problem.

This was, in fact, a makefile parallel dependency problem identified later on the gpsd-dev list. Thanks for your time.