Inherent code performance advantages of D over C?

[Walter Bright]

On 12/8/2013 6:26 AM, qznc wrote:
> On Sunday, 8 December 2013 at 12:35:45 UTC, ponce wrote:
>>> 1. D knows when data is immutable. C has to always make worst case
>>> assumptions, and assume indirectly accessed data mutates.
>>
>> ICC (and other C++ compilers) has plenty of way to disambiguate aliasing:
>> - a pragma to let the optimizer assume no loop dependency
>> - restrict keyword
>> - /Qalias-const: assumes a parameter of type pointer-to-const does not alias
>> with a parameter of type pointer-to-non-const.
>> - GCC-like strict aliasing rule
>
> To be fair, all of these are unsafe optimizations. You only use them after
> carefully identifying the hot spot. D immutability is based on a (probably)
> sound type system and can be used without danger.

To be fairer (!), all of these (except restrict) are non-Standard extensions for 
C. "restrict" is an extension for C++.