[CUDA] added support for Clang (#3886)

.ci/setup.sh

@@ -35,6 +35,7 @@ else  # Linux
             apt-utils \
             build-essential \
             ca-certificates \
+            cmake \
             curl \
             git \
             iputils-ping \
@@ -48,16 +49,16 @@ else  # Linux
             unzip \
             wget \
             zip
+        if [[ $COMPILER == "clang" ]]; then
+            sudo apt-get install --no-install-recommends -y \
+                clang \
+                libomp-dev
+        fi
 
         export LANG="en_US.UTF-8"
         export LC_ALL="${LANG}"
         sudo locale-gen ${LANG}
         sudo update-locale
-
-        sudo apt-get install -y --no-install-recommends \
-            cmake \
-            clang \
-            libomp-dev
     fi
     if [[ $TASK == "mpi" ]]; then
         sudo apt-get update
@@ -84,6 +85,11 @@ else  # Linux
             lsb-release \
             software-properties-common \
             wget
+        if [[ $COMPILER == "clang" ]]; then
+            apt-get install --no-install-recommends -y \
+                clang \
+                libomp-dev
+        fi
         curl -sL https://apt.kitware.com/keys/kitware-archive-latest.asc | apt-key add -
         apt-add-repository "deb https://apt.kitware.com/ubuntu/ $(lsb_release -cs) main" -y
         apt-get update

.github/workflows/cuda.yml

@@ -11,7 +11,6 @@ on:
 env:
   github_actions: 'true'
   os_name: linux
-  compiler: gcc
   task: cuda
   conda_env: test-env
 
@@ -25,12 +24,15 @@ jobs:
       matrix:
         include:
           - method: source
+            compiler: gcc
             python_version: 3.7
             cuda_version: "11.2.0"
           - method: pip
+            compiler: clang
             python_version: 3.8
             cuda_version: "10.0"
           - method: wheel
+            compiler: gcc
             python_version: 3.9
             cuda_version: "9.0"
     steps:
@@ -69,7 +71,7 @@ jobs:
             cat > docker.env <<EOF
             GITHUB_ACTIONS=${{ env.github_actions }}
             OS_NAME=${{ env.os_name }}
-            COMPILER=${{ env.compiler }}
+            COMPILER=${{ matrix.compiler }}
             TASK=${{ env.task }}
             METHOD=${{ matrix.method }}
             CONDA_ENV=${{ env.conda_env }}

CMakeLists.txt

@@ -24,11 +24,7 @@ else()
   cmake_minimum_required(VERSION 3.0)
 endif()
 
-if(USE_CUDA)
-  PROJECT(lightgbm LANGUAGES C CXX CUDA)
-else()
-  PROJECT(lightgbm LANGUAGES C CXX)
-endif()
+PROJECT(lightgbm LANGUAGES C CXX)
 
 if(__INTEGRATE_OPENCL)
   set(__INTEGRATE_OPENCL ON CACHE BOOL "" FORCE)
@@ -117,6 +113,8 @@ else()
 endif(USE_MPI)
 
 if(USE_CUDA)
+    SET(CMAKE_CUDA_HOST_COMPILER "${CMAKE_CXX_COMPILER}")
+    enable_language(CUDA)
     SET(USE_OPENMP ON CACHE BOOL "CUDA requires OpenMP" FORCE)
 endif(USE_CUDA)
 

docs/Installation-Guide.rst

@@ -590,11 +590,11 @@ The CUDA-based build is a separate implementation and requires an NVIDIA graphic
 Linux
 ^^^^^
 
-On Linux a CUDA version of LightGBM can be built using **CUDA**, **CMake** and **gcc**.
+On Linux a CUDA version of LightGBM can be built using **CUDA**, **CMake** and **gcc** or **Clang**.
 
 The following dependencies should be installed before compilation:
 
--  **CUDA** 9.0 or later libraries. Please refer to `this detailed guide`_.
+-  **CUDA** 9.0 or later libraries. Please refer to `this detailed guide`_. Pay great attention to the minimum required versions of host compilers listed in the table from that guide and use only recommended versions of compilers.
 
 -  **CMake** 3.16 or later.