If you use MCC/urpmi, the dependencies will be taken care of for you, but I assume you mean if you manually download gcc, and try like that, then you will have to chase the dependencies yourself I guess, which will be neither enjoyable (unless your a masochist ) or recommended, but not impossible. You will just have to find out what the dependencies are, and install them. How? well, you may be able to find a list in the documentation, or you could just get them one by one as they are reported to you, again, not enjoyable, nor recommended, however perhaps not impossible, I have done similar in the past.
Is there a reason you are using the One version, as apposed to the Free DVD, or CD sets ?, they would contain what you want I believe.
Anyway, other more knowledgeable people may have a better idea for you, just wait a little while and see if anyone bites