GNU GCC

Use GNU gcc version 2.95.2 and configure it with:
configure -with-gxx-include-dir=/usr/local/include/g++
then build it with:
make bootstrap
and do the final installation with:
make install
Have a look at the libraries, for Objectivity you need libstdc++-libc6.1-2.so.3 and libstdc++-libc6.1-2.a.3 in /usr/local/lib and a symbolic link to this files from /usr/lib; also make sure you have a non-zero length library libstdc++-2-libc6.1-1-2.9.0.so pointed to from libstdc++-libc6.1-1.so.2 and the corresponding .a. file (needed for man pages, netscape etc.) in /usr/lib.