Please note: I have not used all of these; one day I was bored and decided to see how many code checking tools I could find packaged for Debian and put them all in a script with the warnings cranked to the max and make that part of my default nightly build and test script. Of course, you can also crank up warnings on your compilers and interpreters as well (-Wall -Wextra, python -tt3 with warnings.simplefilter("always"), perl -tTW with use strict and use warnings, etc)
http://checkstyle.sourceforge.net/
http://cppcheck.sourceforge.net/
http://google-styleguide.googlecode.com/svn/trunk/cpplint/cp...
http://www.dwheeler.com/flawfinder/
http://www.dsm.fordham.edu/~ftnchek/
http://community.haskell.org/~ndm/hlint/
http://jlint.sourceforge.net/
http://search.cpan.org/dist/Perl-Critic/bin/perlcritic
http://deployingradius.com/pscan/
http://pychecker.sourceforge.net/
http://pypi.python.org/pypi/pyflakes
http://www.logilab.org/857
http://packages.debian.org/squeeze/rats
http://www.splint.org/
http://www.incava.org/projects/303902593
http://packages.debian.org/stable/devel/icheck
Please note: I have not used all of these; one day I was bored and decided to see how many code checking tools I could find packaged for Debian and put them all in a script with the warnings cranked to the max and make that part of my default nightly build and test script. Of course, you can also crank up warnings on your compilers and interpreters as well (-Wall -Wextra, python -tt3 with warnings.simplefilter("always"), perl -tTW with use strict and use warnings, etc)