So I am a new programmer and I just installed XCode on my Macbook to get the GCC. I think Xcode is the only way for getting GCC on OSX. Now when I run my Hello World applica
You can have multiple versions of GCC on your box, to select the one you want to use call it with full path, e.g. instead of g++
use full path /usr/bin/g++
on command line (depends where your gcc lives).
For compiling projects it depends what system do you use, I'm not sure about Xcode (I'm happy with default atm) but when you use Makefiles you can set GXX=/usr/bin/g++ and so on.
EDIT
There's now a xcrun
script that can be queried to select appropriate version of build tools on mac. Apart from man xcrun
I've googled this explanation about xcode and command line tools which pretty much summarizes how to use it.