DIP 45 - approval discussion

[Walter Bright]

On 11/17/2013 9:25 PM, Daniel Murphy wrote:
> "Walter Bright" <newshound2 at digitalmars.com> wrote in message
> news:l6c7gt$27fc$1 at digitalmars.com...
>>>
>>> Right, I was saying the indirection still exists.
>>>
>>>
>>
>> No, not really, at least not on Windows. Try calling a function in the
>> Windows API and disassemble it. You'll see a direct call.
>
> You sure about that?
>
> src:
>
> import core.sys.windows.windows;
>
> void main()
> {
>      auto x = GetModuleHandleA(null);
> }
>
> obj:
>
> __Dmain PROC NEAR
> ;  COMDEF __Dmain
>          push    0                                       ; 0000 _ 6A, 00
>          call    dword ptr [__imp__GetModuleHandleA at 4]   ; 0002 _ FF. 15,
> 00000000(segrel)
>          xor     eax, eax                                  ; 0008 _ 31. C0
>          ret                                             ; 000A _ C3
> __Dmain ENDP
>
>
> exe:
>
> ?_0072  LABEL NEAR
>          push    0                                       ; 00402010 _ 6A, 00
>          call    dword ptr [?_0067]                      ; 00402012 _ FF. 15,
> 00401794(d)
>          xor     eax, eax                                ; 00402018 _ 31. C0
>          ret                                             ; 0040201A _ C3
>
>

Try this:

extern (Windows) int GetModuleHandleA(char*);

void main()
{
     auto x = GetModuleHandleA(null);
}

and it compiles and links and runs. No indirection (in the object file, the 
indirection is supplied by linker, triggered by an impdef record in 
kernel32.lib). The "export" isn't actually needed.