You can run it on iOS Devices. You can't build it but must cross-compile on Mac OS X.
There are two compilers - GCC and clang/llvm. Apple's Xcode comes with clang/llvm, for the others one uses gcc.
There are three main things you need: the compiler, the runtime and the libraries.
If you're on windows, use Cocotron.
However I've never actually tried doing so.