when I have tried to compile at least 3 different Qt5 apps (from my ccr) using clang/llvm on chakra (testing) they all have fail with damn same error :
clang-4.0: error: unknown argument: '-fvar-tracking-assignments'
all my 3 pkgbuild do compile just fine on arch so it shouldn’t be a pkgbuild problem, and they do compile just fine using gcc …even more errors with clang/llvm 3.9 (on stable)
here are all the pkgbuilds : download link
PS. apparently LLVM/clang 5.0 will arrive soon