It's too noisy just by itself. First time I tried it, it complained about padding added to structures. When I packed them, it complained about packed structures.
Manually pad them, and it'll complain about unused fields ;)
I've actually had some pieces of code where it was super useful to enable that padding warning as an error. Some complicated C++ types that needed to have identical memory layouts across compilers yet often weren't because of some really nasty shenanigans...
-Weverything is for people who really want to explicitly opt out of every warning they don't like.
it's much better to start from -Weverything and add -Wno-whatever (e.g. -Wno-c++11-compat for instance which complains about C++11 features) than start from -Wall -Wextra etc...
