Can sizeof return 0 (zero)

Question

Is it possible for the sizeof operator to ever return 0 (zero) in C or C++? If it is possible, is it correct from a standards point of view?

Answer 1

If you have this :

struct Foo {}; 
struct Bar { Foo v[]; }

g++ -ansi returns sizeof(Bar) == 0. As does the clang & intel compiler.

However, this does not compile with gcc. I deduce it's a C++ extension.