Forbid dynamic arrays in boolean evaluation contexts

[deadalnix]

On Tuesday, 26 March 2013 at 23:57:32 UTC, bearophile wrote:
> Timon Gehr:
>
>> IOW, what is the point of "null" if you can just use [].
>
> I usually prefer to use [], because null is a literal for 
> pointers and class references, while [] is a literal specific 
> for arrays (and strings), so its meaning is more clear (in D 
> I'd even like a [:] literal that represents an empty 
> associative array).
>
> On the other hand if you compile a program that uses null 
> instead of [] you see some differences. In the current dmd 
> compiler returning null is more efficient. I have seen code 
> where this difference in performance matters:
>
>
> int[] foo() {
>     return [];
> }
> int[] bar() {
>     return null;
> }
> void main() {}
>
>
>
> _D4temp3fooFZAi:
> L0:     push    EAX
>         mov EAX,offset FLAT:_D11TypeInfo_Ai6__initZ
>         push    0
>         push    EAX
>         call    near ptr __d_arrayliteralTX
>         mov EDX,EAX
>         add ESP,8
>         pop ECX
>         xor EAX,EAX
>         ret
>
> _D4temp3barFZAi:
>         xor EAX,EAX
>         xor EDX,EDX
>         ret
>
> Bye,
> bearophile

That is a compiler bug isn't it ?