If pkg_config() fails, try to find the ffi header in /usr/local/include or /opt/local/include
If pkg_config() fails, try to find the ffi header in /usr/local/include or /opt/local/include

MikaelSmith/ffi,yghannam/ffi,MikaelSmith/ffi,sparkchaser/ffi,majioa/ffi,mvz/ffi,MikaelSmith/ffi,sparkchaser/ffi,tduehr/ffi,ferventcoder/ffi,yghannam/ffi,MikaelSmith/ffi,ferventcoder/ffi,yghannam/ffi,ffi/ffi,sparkchaser/ffi,majioa/ffi,majioa/ffi,mvz/ffi,ferventcoder/ffi,majioa/ffi,yghannam/ffi,ffi/ffi,tduehr/ffi,tduehr/ffi,sparkchaser/ffi,yghannam/ffi,mvz/ffi,tduehr/ffi,ferventcoder/ffi,mvz/ffi,ffi/ffi