[Proposal] Switch to the Universal CRT on Windows.

[Adam Wilson]

On Wednesday, 1 July 2026 at 01:24:05 UTC, Adam Wilson wrote:
> I have posted a PR 
> [here](https://github.com/dlang/dmd/pull/23345). This PR 
> deprecates (but still allows) the msvcr120 fallback path as 
> well as updating various detection routines to include the 
> latest versions of VS and deprecate anything prior to VS2015. 
> If no WinSDK or VS installation is detected then the compiler 
> throws an error.

It was noted to me by ADR on Discord that we could keep the 
ability to build without the WinSDK/VS if we included the 
appropriate UCRT library files from MinGW and updated 
`lld-link.exe`.

We might want to consider including more than just the UCRT 
library files from MinGW so we can support building projects that 
need more than the UCRT without requiring the WinSDK. Although, I 
would note that this is a bigger shift into a policy of shipping 
our own complete development environment, with the attendant 
overhead of making sure that environment is up-to-date.