If you ever see a "C compiler cannot create executables" error on Slackware - chances are you are missing a library. Find out the package's library dependencies or for the true slackers, mount your Slackware CD 1, cd to /slackware/l directory and type "installpkg *".

This will install every library which may or may not be desirable depending on the intended use of the machine (i.e. probably not good on a production server :)