What about using gpc under RH7.0 . As I've read gpc is working with gcc 2.95, but under RH7.0 I have gcc 2.96. Now what to do ? I've tried to compile gcc 2.95+gpc but it failed so I don't know what to do.
You didn't say where it failed. Building gpc is actually a by-product of building gcc. You need gcc-2.95.2 *source*. Your present c compiler is used only to get things started. As soon as the build has made a new working c compiler it takes over and finishes the job.
RH 7.0 also packages another gcc compiler, used to build the kernel packages. (2.95.x or so), and it is renamed as kgcc.
I removed in my copy the 2.96 gcc, installed the kernel compiler, and symlinked ls -s kgcc gcc in /usr/bin