D/Objective-C 64bit

[Michel Fortin]

On 2014-03-12 09:26:56 +0000, Iain Buclaw <ibuclaw at gdcproject.org> said:

> On 12 March 2014 07:10, Jacob Carlborg <doob at me.com> wrote:
>> Yeah, since Objective-C uses the C calling convention it's mostly about
>> outputting symbols and data to the object files.
> 
> In what ABI may I ask?  Your choices are:
> - Traditional (32bit) ABI without properties and Obj-C 2.0 additions
> - Traditional (32bit) ABI with properties and Obj-C 2.0 additions
> - Modern (64bit) ABI

I made the 32-bit legacy runtime support, Jacob added the 64-bit modern 
runtime support.

There's no support at this time for properties declarations in the ABI, 
but it doesn't really have much impact. As far as I'm aware, 
Objective-C 2.0 additions only include property declarations and 
attributes in the ABI.


> That can be mixed in with either:
> - GNU Runtime ABI
> - NeXT Runtime ABI

It's been tested with the Apple (NeXT) runtime only. In all honesty, I, 
and probably most people out there, don't care about the GNU runtime. 
Although probably the GCC guys do. Do you think it'd make it more 
difficult to merge GCC in the GCC project if it had support for Apple's 
runtime and not for the GNU one?

Also, is there a list of differences between the two runtimes somewhere?


> Each combination being incompatible with each other subtly different ways...

Which is why we have a test suite.


-- 
Michel Fortin
michel.fortin at michelf.ca
http://michelf.ca