Description of problem:
I built an SRPM in my copr repository, it failed on two out of six chroots:
https://copr.fedoraproject.org/coprs/vjancik/opencv3-deps/build/108924/

and if you look at the build.logs:
https://copr-be.cloud.fedoraproject.org/results/vjancik/opencv3-deps/fedora-rawhide-x86_64/00108924-fawkes/build.log.gz
https://copr-be.cloud.fedoraproject.org/results/vjancik/opencv3-deps/fedora-23-i386/00108924-fawkes/build.log.gz

they contain some weird characters, indicative of some kind of corruption.

I reran the build, with an upped Release tag, to keep the previous build available for this bug report, and it failed completely:
https://copr.fedoraproject.org/coprs/vjancik/opencv3-deps/build/108940/

So I ran it again:
https://copr.fedoraproject.org/coprs/vjancik/opencv3-deps/build/108942/

and it built on all 6 chroots successfully. That is, the same SRPM, though I had to rebuild it because of the Release bump, I can assure you the previous one was good too because I managed to get the failed chroot to build in Koji:

https://koji.fedoraproject.org/koji/taskinfo?taskID=10703586

Additional info:
I am just notifying you about this in case it might be something you can protect against.
My best guess is that the SRPM got corrupted in the upload process, but that doesn't explain why some builds passed and some failed (in different places).