Support for kernel driver compilation using clang-cl from VS 2026

[nullbytepl]

This PR adds support for compiling a WDF kernel driver using clang-cl.

We currently use this setup internally to compile our WDF-based us4oem driver written in C with clang-cl as available in VS 2026.

cc @pjarosik

[SergiusTheBest]

Oh, that's interesting! Thanks for the PR.

[seiftnesse]

Hi everyone,
Looks like I'm not the only one using clang for compilation. I've put together a git patch for my own repo (I originally wanted to submit a proper pull request, but given all the workarounds that clang-cl requires here, I decided against it - but as it turns out, there are like-minded people 😁). This provides full support for building with clang-cl (starting from 19.1.7 using llvm-project). If anyone is able to improve my "patch", I'd really appreciate it.

[nullbytepl]

Hi everyone, Looks like I'm not the only one using clang for compilation. I've put together a git patch for my own repo (I originally wanted to submit a proper pull request, but given all the workarounds that clang-cl requires here, I decided against it - but as it turns out, there are like-minded people 😁). This provides full support for building with clang-cl (starting from 19.1.7 using llvm-project). If anyone is able to improve my "patch", I'd really appreciate it.

@seiftnesse Hi! First of all, thank you for your work! It's clear you know more about these topics than I do 😅. It would likely be impossible for us to transition to fully unifed compiler across our monorepo without it! Using your work, it only took me less than a day of "hacking around" to get it to function properly for our VS+clang-cl-based project with a Windows userspace library, WDF-based driver and userspace/kernel, OS agnostic hardware access library. Guess you can now say you've contributed something to the field of ultrasound research 😀

As for your patch, I'll definitely take a deeper look at it and integrate it into our PR whenever I find free time at the office. I'm guessing our changes diverge when it comes to the linker flags because we use the MSVC linker and not lld-link, so I'll try to accommodate for that too.

[nullbytepl]

@seiftnesse your new patch mentions "wdk_smoke_check_no_sse.cmake" but it seems to be missing from the commit, could you add that somewhere?

[seiftnesse]

Hi there,

Guess you can now say you've contributed something to the field of ultrasound research 😀

I'm glad to hear that!

@seiftnesse your new patch mentions "wdk_smoke_check_no_sse.cmake" but it seems to be missing from the commit, could you add that somewhere?

My bad, forgot to include it. wdk_smoke_check_no_sse.cmake is just a small tool that catches SSE/AVX instructions and self-recursive functions. I'll push it right now.