Don’t overlook the compiler itself. Read the compiler’s documentation and find all the warnings and errors it can provide, and then enable as many as make sense for you.
Also make sure to tell your compiler to treat warnings like errors so you’re forced to fix them right away (-Werror on gcc).
By the way, don’t be fooled -Wall on gcc does not enable all warnings.
You may want to check valgrind (free!) — it “automatically detect[s] many memory management and threading bugs, and profile[s] your programs in detail.” It isn’t a static checker, but it’s a great tool!