xgboost: CMakeLists.txt does not respect CUDA_HOST_COMPILER

{ config, stdenv, lib, fetchFromGitHub, cmake, gtest, doCheck ? true

, cudaSupport ? config.cudaSupport or false, ncclSupport ? false

, rLibrary ? false, cudaPackages, llvmPackages, R, rPackages }:

{ config

, stdenv

, lib

, fetchFromGitHub

, cmake

, gtest

, doCheck ? true

, cudaSupport ? config.cudaSupport or false

, ncclSupport ? false

, rLibrary ? false

, cudaPackages

, llvmPackages

, R

, rPackages

}:

assert ncclSupport -> cudaSupport;

# Disable regular tests when building the R package

  cmakeFlags = lib.optionals doCheck [ "-DGOOGLE_TEST=ON" ]

    ++ lib.optionals cudaSupport [

    "-DUSE_CUDA=ON"

      "-DCUDA_HOST_COMPILER=${cudaPackages.cudatoolkit.cc}/bin/cc"

    ] ++ lib.optionals (cudaSupport

    # Their CMakeLists.txt does not respect CUDA_HOST_COMPILER, instead using the CXX compiler.

    # https://github.com/dmlc/xgboost/blob/ccf43d4ba0a94e2f0a3cc5a526197539ae46f410/CMakeLists.txt#L145

    "-DCMAKE_C_COMPILER=${cudaPackages.cudatoolkit.cc}/bin/gcc"

    "-DCMAKE_CXX_COMPILER=${cudaPackages.cudatoolkit.cc}/bin/g++"

  ] ++ lib.optionals

    (cudaSupport

      && lib.versionAtLeast cudaPackages.cudatoolkit.version "11.4.0")

    [ "-DBUILD_WITH_CUDA_CUB=ON" ]

    ++ lib.optionals ncclSupport [ "-DUSE_NCCL=ON" ]