I need a tool which helps me to find memory leaks in a c program in a similar way valgrind does. It should figures out when a program overwrites memory it should not (e.g. by miscalculating an array index). I learned that there is the leaks utility along with the graphical instruments app.
However I think it can just find memory allocated with new (or malloc) which was not released and is not accessible anymore. Also I learned that valgrind is supposed to work on older releases (10.5 and 10.6), but I use lion (10.7).