Would somebody be willing to explain how to use pkgsLLVM to me? My goal is to cross compile using clang, and I know that pkgsLLVM is key, but can't really see how to use it. Additionally, to select the CPU and FPU, do I pass config = { mcpu = "<cpu>"; mfpu = "<fpu>"; }; respectively? Sorry if this is a noob question!

Moreover, is there a way to set sysroot to a different root (i.e. copied off of the target's filesystem)?

In reply to @tpool:matrix.org

Would somebody be willing to explain how to use pkgsLLVM to me? My goal is to cross compile using clang, and I know that pkgsLLVM is key, but can't really see how to use it. Additionally, to select the CPU and FPU, do I pass config = { mcpu = "<cpu>"; mfpu = "<fpu>"; }; respectively? Sorry if this is a noob question!

Moreover, is there a way to set sysroot to a different root (i.e. copied off of the target's filesystem)?

Import nixpkgs with

crossSystem = {
  config = "something";
  useLLVM = true;
  gcc = {
    cpu = "<cpu>"
    fpu = "<fpu>";
  };
};

In reply to @tpool:matrix.org

Would somebody be willing to explain how to use pkgsLLVM to me? My goal is to cross compile using clang, and I know that pkgsLLVM is key, but can't really see how to use it. Additionally, to select the CPU and FPU, do I pass config = { mcpu = "<cpu>"; mfpu = "<fpu>"; }; respectively? Sorry if this is a noob question!

Moreover, is there a way to set sysroot to a different root (i.e. copied off of the target's filesystem)?

Import nixpkgs with

crossSystem = {
  config = "something";
  useLLVM = true;
  gcc = {
    cpu = "<cpu>";
    fpu = "<fpu>";
  };
};

So this expression is really slow, because it tries to build all of the dependencies:

nix-build '<nixpkgs>' --arg crossSystem '(import <nixpkgs/lib>).systems.examples.raspberryPi'  -A hello &| nom