Can we kill the D calling convention already?

[Don Clugston]

On 25/04/12 17:05, Paulo Pinto wrote:
> On Wednesday, 25 April 2012 at 14:32:13 UTC, Alex Rønne Petersen wrote:
>> On 25-04-2012 15:06, Kagamin wrote:
>>> On Tuesday, 24 April 2012 at 10:29:52 UTC, Alex Rønne Petersen wrote:
>>>> The point is just that: Right now I can write assembly that will work
>>>> on GDC, LDC, and DMD on non-Windows. It will not work for DMD on
>>>> Windows. Something has to change here.
>>>
>>> If it doesn't work on Windows, it should be versioned out. What we have:
>>> http://dlang.org/version.html#PredefinedVersions - versions for LDC,
>>> GDC, DMD and Windows - all what you want.
>>
>> Yes, I added them. :)
>>
>> You're missing the point. D is providing (or trying to provide) a
>> standard inline assembler, but calling conventions are not
>> standardized enough for it to be useful across compilers. If you're
>> writing inline assembly because you *have* to, you don't just "version
>> it out", you have to write different logic for different compilers,
>> which is a maintenance nightmare.
>
> This is exactly what C++ gets blamed for, yet most people fail to
> realize that the situation is common to all languages that generate
> native code.

No, it's totally the fault of C++. C++ failed to specify it, so everyone 
did something different. Then you get this very unfortunate mindset 
where everyone is so used to it, they don't find it unacceptable any more.

> The only reason it works out for C, is that the C ABI is actually the OS
> ABI, as such all C compilers tend to have a common ABI.

Not true. The ABI for Win32 is __stdcall, not C. Pascal and Fortran 
calling conventions were always well standardized, too.

> It would be nice if I could use D libraries without having to worry
> which compiler was used to generate them.

Yes. This is mandatory.

It'd be fantastic if we had a calling convention that depended ONLY on 
the CPU, not on the OS. But I don't know if it is feasible. The 
Windows64 calling convention is standardized, and it's different to the 
Linux64 one.

I don't know if it's even possible to use a different calling convention 
on Win64, there are interactions with system exception handling.