I'd bet a weeks salary (seriously) that Coverity (yeah yeah it's expensive, whatever) will catch > 90% of these with maybe a 10% false positive, and Code Analysis in VS would hover around the 80% mark with maybe a 15% false positive (both for C++; for ANSI C, move that up to 95% and 90% accordingly).

ccc-analyzer/c++-analyzer for clang/llvm would probably hit the 90-ish mark for ANSI C too.