The whole point of SDL is that it can compile and run on many different platforms. But you have to use SDL for all the platform stuff. If you didn't use SDL for the window, input, rendering, file I/O, and threading, then you will most likely have to refactor your code to use SDL for everything. But like ApochPiQ said, without seeing the code it's really hard to tell.
I do know you can compile an SDL program from the command line on a Mac because I've done it. There were a few difference, like OpenGL headers being in a different place, but those kinds of things are solved by adding some #ifdef calls to some header files.