In the olden days[tm] there was a project for maintaining a Delphiversions.inc file which created human readable conditional defines from the VERxx conditional defines of the Delphi compilers. Since it seems to have vanished from the face of the Internet[tm], I have just added a new page to the Delphi Wiki which you can just copy to a file and use. It allows you to do things like this:
{$include 'Delphiversions.inc'}
{$IFDEF Delphi6_up}
{$WARN unsafe_type off}
{$WARN unsafe_code off}
{$WARN unsafe_cast off}
{$ENDIF}
(This turns the annoying dotNET warnings off that are just so unnecessary for native code.)
For a more comprehensive version of such a file, see jedi.inc from Project JEDI.