[kazinator]

To clarify, it could be that the bottom type is not the base of all types, if the language has a split between some types which participate in that sort of thing and others that don't (e.g. class versus basic types or whatever).

But void is not the base of anything in C and C++.

You could argue that void is in some category of types where it is at the bottom; but no other types are in that category.

There is another problem: a bottom type should be the subtype of all types in that category. That includes being its own subtype. There we have a problem: C and C++ void is not a subtype of void in any sense.