Zero initializing also hides bugs. Say you have some code that should not be reading the initial state and is buggy if it does. Without zero-init, valgrind and

Zero initializing also hides bugs. Say you have some code that should not be reading the initial state and is buggy if it does. Without zero-init, valgrind and msan will give you an immediate and false positive message that your code is wrong-- or forget dynamic analysis: the compiler can often statically tell you that the code will use an uninitialized variable. Zero initialize it and you lose that signal.