jperkin, 
So unfortunately #LLVM 17 has hit #pkgsrc, which means I need to turn off support for the full LLVM suite in #clang on #illumos
We offered to provide build hosts and maintain support, but upstream weren't interested, and removed all of the code.
Given it was working absolutely fine, this is a real shame. Especially as I spent a significant chunk of time getting it working.
It'll now have to go back to depending on GCC's libstdc++, and I'll work on avoiding dependencies on clang where I can.
