ehlo,
INT64_C(n) will expand to something appropriate for any n in (at least) a
64-bit range (see §7.18 in general, and particularly §7.18.4.1).
http://www.open-std.org/JTC1/SC22/WG14/www/docs/n1256.pdf
You can see a warnings only on 32 bit architecture.
So the simplest reproducer is to rebuild sssd in 32 bit chroot in mock
mock --root epel-6-i386 --resultdir . --rebuild ./sssd-1.13.90-0.fc23.src.rpm
LS