[OE-core] [meta-clang] clang/LLVM versioning

[Martin Kelly]

Hi,

I'm attempting to build a recipe using the LLVM/clang cross toolchain 
provided in meta-clang. However, I'm hitting issues with the llvm-config 
wrapper in llvm-common. Specifically, it looks like the wrapper was 
copied over from the LLVM recipe in meta-oe, but the versioning logic 
was not updated, so when the wrapper attempts to exec the versioned 
llvm-config-${WANT_LLVM_RELEASE}, it fails. Notably, LLVM_RELEASE is not 
set in meta-clang/recipes-devtools/clang/clang.inc.

I'm looking into fixing the wrapper, but before I go too far down that 
path, I wanted to get clarification as to the intention of how 
versioning is handled in meta-clang. Specifically, the original LLVM 
recipe was clearly built to support multiple side-by-side LLVM versions 
on the same system. Do we have the same goal for meta-clang? IOW, should 
I make sure that the versioning logic works for meta-clang, or should we 
instead just abandon the versioning (and the wrapper) and support a 
single version of clang/LLVM?

Thanks,
Martin