Just one more thing...

[Sean Kelly]

Brad Roberts wrote:
> Michel Fortin wrote:
>> On 2009-02-27 16:37:13 -0500, Jacob Carlborg <doob at me.com> said:
>>
>>> Nick Sabalausky wrote:
>>>> Ordinarily, I detest the idea of pulling support for anything as
>>>> recent as just a few years old. But Apple themselves has a habit of
>>>> ignoring users of anything except the latest version, so I would
>>>> think that mac users would be accustomed to the old routine of their
>>>> OS becoming a deadend the moment a new version comes out. So, in this
>>>> case, I would think that there may actually be justification in
>>>> sticking with 10.5+, if you were to so choose.
>>> I would not completely agree with you on this. When you install the
>>> developer tools on osx 10.5 it installs SDKs for 10.5 and 10.4 as
>>> default, but you can also choose to install support for older
>>> versions. I'm not sure if it's only for 10.3 or also for 10.2.
>> On Mac OS X 10.5, you can compile for 10.3 using Xcode 3, and 10.2 using
>> Xcode 2.5 (Xcode 2.5 for Leopard is a free download). Of course, 10.2
>> and 10.3 being PowerPC-only, there's no point trying to compile DMD for
>> them.
> 
> You can do that if and only if you don't require newer apis.  If you've
> been reading this thread, you know that the runtime uses the posix
> thread apis and those are supported less and less well as you go back in
> time.  The ability to support the old versions isn't some magic wand
> that conjures up new features into those old releases.

One somewhat weird issue that we may have to face at some point is that 
Posix functions whose behavior was changed have had the symbol for the 
new function changed to _blah$UNIX2003, with the old function left in 
place.  Since D can't declare symbols like this, we may end up having to 
add shims in C or post-process object files if it turns out that the old 
implementation of a function isn't sufficient.  I'd love to hear of a 
better solution here.