Can someone decipher this moon speak for me? (abi - calling conventions)

[Bernard Helyer]

http://dlang.org/abi.html

"The extern (C) and extern (D) calling convention matches the C 
calling convention used by the supported C compiler on the host 
system. Except that the extern (D) calling convention for Windows 
x86 is described here."

Was this written by someone slamming their face onto the keyboard 
repeatedly? Is the calling convention just C on non-windows 
platforms? What about AMD64? Why should I, as someone writing a D 
implementation, burn cycles on trying to decypher this madness? 
Didn't this section _used_ to make sense?

To summarise:





fucking what?






</rant>