I have Knoppix 7.30 installed on a USB with a persistent file. It comes with GCC 4.7.2. I would like to install GCC 4.9.x or 4.8.x. Being that Knopppix is based on Debian I would normally do something like apt-get upgrade But as far as I understand it's not recommended to do this with Knoppix.

Warning: apt-get upgrade is a BAD IDEA. It will, quite probably, render your KNOPPIX remaster unbootable, or broken in some way. A far safer method is to only upgrade packages as necessary.

I can say from experience that that is the cse.

So how should I go about installing GCC 4.9? Another option would be to "remaster" knoppix to use GCC 4.9 by default rather than install it with a persistent file. I would be happy with either solution.