empty base class optimization

Question

Two quotes from the C++ standard, §1.8:

An object is a region of storage.

Base class subobjects may have zero size.

I don\'t

Answer 1

A philosophical argument over the definition of "region" is unnecessary.

1.8/5 says, "Unless it is a bit-field, a most derived object shall have a non-zero size ... Base class sub-objects may have zero size".

So the standard is quite clear what objects (and hence what "regions of storage") can have zero size. If you disagree with the standard what "region" means in English that's one thing, you can fault the authors' (non-programming-related) literary skills. For that matter you can fault their poetic skills (14.7.3/7) But it's quite clear what the standard says here about the sizes of objects of class types.

The pragmatic way to read standards is that given two plausible interpretations of a word, choose the one which doesn't directly contradict another sentence in the same section of the standard. Don't choose the one which matches more closely your personal preferred use of the word, or even the most common use.