Compile error

I’ve suddenly started getting an error at compile time - “ld: framework not found libsystem.dylib”
I can run in the simulator. I’ve deleted the caches folder.
I’ve checked I have a provisioning profile selected.

Any ideas on where to begin trouble shooting next?

Do you have any declares into “libsystem”? If so make sure the S is capitalized in system.

That was it Jason. Thank you

I’m running El Capitan, and after capitalizing the ‘S’, I also had to pass the full path /usr/lib/libSystem.dylib
It seems the new "System Integrity Protection"in Mac OS X 10.11 prevented linking when the full path was not used.