Unused druntime code: Barrier, ReadWriteMutex, Condition

[Denis Feklushkin]

On Monday, 15 June 2026 at 21:06:16 UTC, Walter Bright wrote:
> Thank you for your work supporting FreeRTOS!
>
> I recommend checking github on the history of those functions. 
> The PR's for them may give a rationale for their existence.

In dmd repository first commit containing mentioned above classes 
is literally the first commit that makes any sense:
```
commit 6837c0cd426f7e828aec1a2bdc941ac9b722dd14 (HEAD)
Author: Sean Kelly <sean at invisibleduck.org>
Date:   Fri Sep 19 02:35:12 2008 +0000

     First commit of the D Runtime Project.  This includes a fully 
functional runtime for DMD/D1.  Support for DMD/D2 is next on the 
agenda.
```
And I see that this classes simply exist and are not used 
anywhere.

I used commands like:
```
git log -G " Barrier"
```
to find anything. I also searched in Phobos repository and didn't 
find anything. Github reports one unsuccessful attempt to make PR 
with ReadWriteMutex, but it was declined.

Maybe I'm looking in the wrong place, I'm not a big expert on git 
kung fu.