This is GNU GCC 2.95.2, compiled to support C, C++, Objective-C, Fortran-77, Java, and Chill. It is supplied as an alternate compiler for Slackware. It's not very well tested at this time for things like compiling the kernel and system software, so if you use it for such things you are on your own. It actually was part of Slackware's D series in slackware-current for a short time, until the Linux 2.2.15 kernel shipped and it was discovered that parts of it won't compile with gcc-2.95.2. For compiling the kernel, egcs-1.1.2 (or even gcc-2.7.2.3) are better choices. To make this your default compiler, just install these packages with 'installpkg'. If you decide later to switch back to egcs, just remove the packages with 'removepkg' and then reinstall egcs with 'installpkg'.