Support Windows XP

[Steven Schveighoffer]

On 5/3/21 6:43 AM, user1234 wrote:
> On Monday, 3 May 2021 at 09:53:42 UTC, Dukc wrote:
>> On Sunday, 2 May 2021 at 18:15:04 UTC, Imperatorn wrote:
>>> I modified the PE header (set major version and subsystem to 5) and 
>>> it worked 🌞
>>>
>>> No idea how much ub this causes tho.
>>
>> Care to explain this in beginner-friendly way? I think it's likely it 
>> will help other people with same kinds of problems.
>>
>> DMD for Windows should work just as well in XP as in later versions, 
>> as far as I know. I don't think it depends on any functionality 
>> introduced after XP.
> 
> operating system + druntime bindings might be the only issue.
> 
> Support for XP was dropped because it went EOL and that's it.
> The compiler itself just needs to read files, write files, call 
> processes and that's it.

Typically, the reason D stops supporting older OSes is because something 
changes that is fundamental to the language.

My understanding is that something changed in how thread-local-storage 
is supported, so XP is no longer valid for the current compilers. I 
could be wrong, but I'm pretty sure there was a definite reason for 
dropping support, even if it wasn't TLS.

Of course, you can still use an older compiler.

-Steve