[amouat]

Depends what you mean by "proper". Any fool can get a C program to work, but ensuring there are no memory leaks etc is very hard without a tool like Valgrind.

If you don't believe me, just run Valgrind on random sampling of C programs that didn't use such a tool - I reckon it will find issues with most of them.

[dap]

Valgrind (and tools using its methodology) isn't the only way to solve these problems. Libumem finds memory leaks too, and without imposing an immense runtime cost. It also finds many types of memory corruption without the runtime overhead that often changes the program's behavior that you're trying to debug.

[popee]

Agreed. Valgrind can be very helpful, saved me few times. You know huge modular application, one line bug, dead end situation. Too bad output is mess, ups, full of details :-)