You shouldn't need to download anything. FC2 comes with gcc, it'll be on your installation disc(s). Slap the disc in the drive, run the software installer from the main menu system, enter the root password if prompted, select gcc (it'll be in the development section) then install both gcc and any oother files it suggests are needed. Then, in a console, do
rpm -qa |grep -i gcc , which should return a familiar looking list of package names (i.e. those you just installed.) The $CC variable will be taken care of automagically.