Calling Valgrind a "memory leak detector" totally underplays its usefulness. But for some reason I've never worked out, a lot of people think this is all it doe

Calling Valgrind a "memory leak detector" totally underplays its usefulness. But for some reason I've never worked out, a lot of people think this is all it does. The main things that Memcheck, the default Valgrind tool, do are: 1. Detect accesses to inaccessible memory. 2. Detect dangerous uses of undefined values. 3. Detect memory leaks. Memory leaks are arguably the least interesting of these three things. ASAN can do 1 and 3, but cannot do 2. That's why Mozilla runs both Valgrind and ASAN on Firefox test automation. There's a tool related to ASAN called MSAN that attempts to do 2, but 2 is really hard to do with static instrumentation so MSAN doesn't get much real-world use.