> Can you clarify what exactly compiler-rt is and how important it is to the > stack as a whole. It seems that llvm-toolchain-3.7 built successfully on > raspbian without building compiler-rt while llvm-toolchain-3.8 built an > armv7 compiler-rt (and hence got blocked from entering the raspbian repos).
Compiler-rt is the equivalent of libgcc, and Clang can use the existing host's libgcc quite happily so it's really not that important unless you're trying to build a GNU-free environment for whatever reason. Cheers. Tim.