Support clang build on windows.

[gengjiawen]

We have run into multi issues using msvc compiler. Is it possible we add clang support for windows too.
Some benefits:

• v8 use clang on windows too, v8 build will be less problematic.
• clang is small compared to visual studio
• ninja support

cc @nodejs/v8 @nodejs/build

[targos]

It's possible if someone does the work to enable it.

[ryzokuken]

@gengjiawen it sounds like a major win. As @targos said, I hope someone finds the time and energy to make this happen.

[richardlau]

This is probably one for @nodejs/platform-windows (in particular @joaocgreis and @bzoz). As long as Node.js supports building with MSVC we'll need to continue building on it so adding an additional toolchain (clang) doesn't avoid us having to fix the build with MSVC.

[gengjiawen]

an additional toolchain (clang) doesn't avoid us having to fix the build with MSVC.

Actually v8 doesn't use msvc bring too much trouble when we building Node.js.If this is doable, we can move msvc support to second layer ?

The biggest problem with msvc is that, it's very hard to debug with all those mistery.
It often take many days to debug a msvc-only problem like in this repo and bnoordhuis/v8-cmake#10.

[mmarchini]

It would be amazing if we could do so, and it had been suggested before by V8. One thing to consider is that such a change would be semver-major, and the biggest challenge is ensuring native modules still work (and I'm not sure if native modules would need a different toolchain with clang instead of msvc, @nodejs/platform-windows might know it). As soon as we had this working it would be feasible for us to use clang to test this repo, since V8 updates are semver-major by default.

[targos]

I started experimenting with ClangCL here: https://github.com/targos/node/commits/clang-cl
Currently blocked on ICU: nodejs/node#34201

[targos]

Work is happening on nodejs/node#35433