The current development version of Splint is available through SourceForge CVS. Be warned that the development version may not be fully tested and may contain work in progress.
For directions on obtaining it visit: http://sourceforge.net/cvs/?group_id=34302
To build splint from the CVS code, you need to have autoconf and automake installed on your system. You may obtain them from: http://ftp.gnu.org/gnu/autoconf/ and http://ftp.gnu.org/gnu/automake/.
See the source code installation instructions for information on compiling and installing Splint.