Edit: /usr/lib64/pkgconfig/libffi.pc (226B)
prefix=/usr
exec_prefix=/usr
libdir=/usr/lib64
includedir=${libdir}/libffi-3.0.5/include
Name: libffi
Description: Library supporting Foreign Function Interfaces
Version: 3.0.5
Libs: -L${libdir} -lffi
Cflags: -I${includedir}