What is a Good Open Source Code Analysis Tool?

carlmenezes asks: "I volunteer when I can to help a poor educational institution in India with their computing needs. As you can imagine, most computers are from donations and very little money (if any) can be spent on software licensing. Therefore, the installed software is all Open Source and I do all of the software installation by myself. I have already installed Linux on 16 PCs, with Firefox. The default desktop is KDE and the kdeedu package (klettres in particular) has several loyal fans. Incidentally, the kids don't find it hard to use at all and the lack of 3D doesn't bother them in the least :) I would like to ask the community about a good source code analysis tool. I have already installed Source Navigator. Is there any other comparable open source tool?" "The analysis tools would be for those students that show more interest than the others in programming. There is a lot of source code in there for them to look at it if they want to. I'm looking more at C/C++ than anything else. There are some very bright students and I would like them to be able to move beyond ordinary school programming if they feel like it. No, there is no Internet connection. I bring in the software on CDs and install it."