Added shader-slang-llvm which sets withLLVM = true; so this gets catched by nixpkgs-review and built by hydra in the future. However, I came to realize that the final binaries and libraries do not seem to link to LLVM anymore when withLLVM = true;. I'm pretty sure this used to be different when I originally created this package, so we should try to figure out what's going on here before merging (to make LLVM support actually work).

In the shader-slang repository, only slang-test seems to explicitly link against slang-llvm. How is LLVM mode supposed to work? As libslang-llvm.so also does not seem to be loaded at runtime by libslang or slangc, only by slang-test.

@niklaskorz yeah actually, as far as I'm aware, Slang pretty much only uses LLVM for FileCheck in testing. I'm not aware of any uses of LLVM in Slang other than testing (although I could be wrong).

In that case do you think we should maybe just remove LLVM from Slang in Nixpkgs?

OK never mind, I was incorrect; I asked Yong and he said:

Slang-llvm also provides the clang-llvm backend to generate code from c++ source without going through a system c++ compiler.

So it seems like slang-llvm is indeed not meant to be used by libslang or slangc, but the intention is that others can link against lib/libslang-llvm.so if they want.

@niklaskorz I don't see lib/libslang-llvm.so in the shader-slang-llvm package when I build it though; do you know why?

So it seems like slang-llvm is indeed not meant to be used by libslang or slangc, but the intention is that others can link against lib/libslang-llvm.so if they want.

@niklaskorz I don't see lib/libslang-llvm.so in the shader-slang-llvm package when I build it though; do you know why?

I see, in that case it might be best to always build it and move it to a separate output llvm (so instead of having a package shader-slang-llvm, it would be accessed as shader-slang.llvm).

As for why the library is missing from the output, that is because the target is missing the INSTALL property. We could patch it in manually if not installing the library is intended by upstream.

Superseded by #437524.