You can build (partially) with LLVM toolchain using the useLLVM flag.
This works like so:
nix-build -A hello --arg crossSystem '{ system =
"aarch64-unknown-linux-musl"; useLLVM = true }'
also don’t separate debug info in lldClang
It doesn’t work currently with that setup hook. Missing build-id?
* llvm: build w/polly in-tree, optionally
Don't enable by default yet, defer rebuilds.
* top-level: llvm-polly, clang-polly
* bit hacky re:overrides
* need to explicitly set cmake flags for clang to link in polly