Porting windows to Mac

Hi everyone. I’ve developed an SDL-based game in C++ in Dev Bloodshed C++. I know SDL is cross platform, so I figure I ought to be able to build the game from source for Mac OSX as well. But I’m also sure it’ll require some modification (DLLs aren’t relevant, makefile probably needs alteration) and was wondering if anyone had any good pointers on what typically needs to be done or what the process should be. I’ll be using XCode unless recommended otherwise, and I’ve got a PPC Mac but would like to have it run on Intel too. Thanks in advance!