Three Cool Things about D

[David Nadlinger via Digitalmars-d-announce]

On Wednesday, 23 December 2015 at 01:07:57 UTC, Walter Bright 
wrote:
> On 12/22/2015 10:29 AM, David Nadlinger wrote:
>> Not sure about how it arrives at the crazily unrolled loop, 
>> but no recursion in
>> sight anymore.
>
> It's doing tail recursion optimization, which turns the 
> recursion into a loop.

The recursive call is not quite a tail call by itself, which is 
what Andrei pointed out using that example. But yes, that's what 
happens.

> Then the loop is unrolled 8 times.

Sure thing. I was rather surprised to see that happen given that 
I only compiled with -O1, though, as it seems to be quite an 
aggressive optimization.

  — David