Inherent code performance advantages of D over C?

[Max Samukha]

On Thursday, 12 December 2013 at 17:56:12 UTC, Walter Bright 
wrote:

> 11. inline assembler being a part of the language rather than 
> an extension that is in a markedly different format for every 
> compiler

Ahem. If we admit that x86 is not the only ISA in exsistence, 
then what is (under)specified here http://dlang.org/iasm.html is 
a platform-specific extension.