If you look at many iOS libs they are actually fat binaries, meaning they usually have x86, armv6, and armv7 executable code in them. On iOS cross-compilation

If you look at many iOS libs they are actually fat binaries, meaning they usually have x86, armv6, and armv7 executable code in them. On iOS cross-compilation only occurs when you target an iOS device such as an iPhone which generates armv6 and armv7 code.