I can make a pull-request for this since I already have this setup in my local branch.

Thanks! ov-l. Assigned the issue to you :)

Side note: you might have to be careful as of what is imported in case of cross-compilation (e.g., to WebAssembly), though I'm not used to configuring CMake installs so it might work out of the box.

For my use case I've had to manually deal with it so that slangc executable is setup for the native system while slang library is setup for the target system: FetchSlang.cmake

I added slang as the only target because I just needed that for my use case. If you intend to link with slang, that should work out of the box. slangc on the other hand would be a different target which I have not included in the export target list, and the executable is already installed by default by the existing cmake script (if you build the executable).
With modern CMake, if you just link with slang::slang, it should be all good on all platforms normally, unless something is wrong in the original CMake script with target setup. I personally tested on linux and windows, both work fine.

I am having a hard time figuring out what is requested initially.
It says "import of precompiled binaries", and I am not sure where it is supposed to be imported to.
And what is the use case for this.

@eliemichel , can you clarify my questions so that we can provide a proper support?

@eliemichel , can you clarify my questions so that we can provide a proper support?

Sure, I meant "import" as in CMake's vocable of "imported targets" that can be manually created with e.g., add_library(foo STATIC IMPORTED). The typical way to equip a binary release of a library (be it static or shared) so that it can be properly imported by CMake's find_package mechanism (in so-called "Config" mode) is to provide a SlangConfig.cmake file (in lib/cmake IIRC).

In our case, that would mean if download and unzip a binary release to /path/to/slang, then configure a project with cmake -DSlang_DIR=/path/to/slang (or add this path to CMAKE_PREFIX_PATH): after that simply calling find_package(Slang REQUIRED) in my CMakeLists.txt would make available the Slang targets (static, shared, executable targets -- whether the release provides).

Aside from manual download, this is also very compatible with FetchContent-based approaches to fetch the precompiled binaries and internally (i.e., inside some FetchSlang.cmake's dynamics) automatically set Slang_DIR to the place where it did download the release.

I believe the approach proposed in #5674 is sound, although I wouldn't consider myself an expert in CMake's import/export mechanism. But let me know if there is actually another recommended way of doing all this!