I agree that it will compile just fine. Note that nvidia supplies a file called Module-nvkernel in their srpm and tgz files. This is their binary kernel module, and is not recompilable by the end user. Like thunderbird said, the opensource part of the driver is the 'glue', not the guts.
To see the error I'm getting, compile your kernel with gcc3.2, install it, and try to load the binary nvidia module. You'll get the same error message I posted above. Or, you could install the latest redhat beta called (null) and have an identical install base to what I'm using. (null) will probably be released as Redhat 8.0 in the coming month or two.
All of my work is being done with a freshly installed system and newly downloaded files. There isn't a chance of a tainted build here from leftover files.