nixpkgs/pkgs/development/compilers/llvm/12/libunwind/default.nix

{ lib, stdenv, llvm_meta, version, fetch, libcxx, llvm, cmake
, enableShared ? !stdenv.hostPlatform.isStatic
}:

stdenv.mkDerivation rec {
  pname = "libunwind";
  inherit version;

  src = fetch pname "1x8wpmsrsgnwj2v5ih52ylni7r6n8gzkcj6hx65zbxski2rablly";

  postUnpack = ''
    unpackFile ${libcxx.src}
    mv libcxx-* libcxx
    unpackFile ${llvm.src}
    mv llvm-* llvm
  '';

  nativeBuildInputs = [ cmake ];

  cmakeFlags = lib.optional (!enableShared) "-DLIBUNWIND_ENABLE_SHARED=OFF";

  meta = llvm_meta // {
    # Details: https://github.com/llvm/llvm-project/blob/main/libunwind/docs/index.rst
    homepage = "https://clang.llvm.org/docs/Toolchain.html#unwind-library";
    description = "LLVM's unwinder library";
    longDescription = ''
      The unwind library provides a family of _Unwind_* functions implementing
      the language-neutral stack unwinding portion of the Itanium C++ ABI (Level
      I). It is a dependency of the C++ ABI library, and sometimes is a
      dependency of other runtimes.
    '';
  };
}