[PATCH] __attribute__((bitwise))
Handling of __attribute__((bitwise)) in a way that should be easy to extend
afterwards. Example of use:
typedef __u32 __attribute__((bitwise)) __le32;
That will create a new 32bit type that will be assignment-incompatible with
anything else. The set of allowed operations is restricted to bitwise ones,
the only allowed constant is 0 right now. Forced casts are allowed, so is
cast from type to itself and cast to void. Any other cast will give a warning.
Checks are triggered by -Wbitwise in command line; if it's not there,
attribute will be silently ignored.