conditional compilation and -v1

[Lutger]

I'm having some trouble finding out how it is possible to conditionally
compile code depending on which version of D is set. 

This is from the spec about the version statement: "It is inevitable that
the D language will evolve over time. Therefore, the version identifier
namespace beginning with "D_" is reserved for identifiers indicating D
language specification or new feature conformance."

There doesn't seem to be a v1 version identifier however, is this a bug or
should it be filed as one?