From 512de79ffc470445de8a6216e895ff28f9266123 Mon Sep 17 00:00:00 2001
From: Peter Heywood <peethwd@gmail.com>
Date: Tue, 10 Aug 2021 16:27:24 +0100
Subject: [PATCH] Add support for clang as the host complier

Add clang to the CI build matrix
Add clang-specific warning suppressions
---
 .github/workflows/Ubuntu.yml | 14 ++++++++++++++
 cmake/warnings.cmake         |  9 +++++++--
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/Ubuntu.yml b/.github/workflows/Ubuntu.yml
index 9e70d44d3..60d6ed71f 100644
--- a/.github/workflows/Ubuntu.yml
+++ b/.github/workflows/Ubuntu.yml
@@ -37,6 +37,10 @@ jobs:
             cuda_arch: "35"
             hostcxx: gcc-11
             os: ubuntu-22.04
+          - cuda: "11.8"
+            cuda_arch: "35"
+            hostcxx: clang-14
+            os: ubuntu-22.04
           - cuda: "11.0"
             cuda_arch: "35"
             hostcxx: gcc-8
@@ -113,6 +117,16 @@ jobs:
         echo "CXX=/usr/bin/g++-${gcc_version}" >> $GITHUB_ENV
         echo "CUDAHOSTCXX=/usr/bin/g++-${gcc_version}" >> $GITHUB_ENV
 
+    - name: Install/Select clang and clang++
+      if: ${{ startsWith(env.HOSTCXX, 'clang')}}
+      run: |
+        clang=${{ env.HOSTCXX }}
+        clang_version=${clang/clang-/}
+        sudo apt-get install -y clang-${clang_version} clang-tools-${clang_version}
+        echo "CC=/usr/bin/clang-${clang_version}" >> $GITHUB_ENV
+        echo "CXX=/usr/bin/clang++-${clang_version}" >> $GITHUB_ENV
+        echo "CUDAHOSTCXX=/usr/bin/clang++-${clang_version}" >> $GITHUB_ENV
+
     - name: Select Python
       if: ${{ env.PYTHON != '' && env.FLAMEGPU_BUILD_PYTHON == 'ON' }} 
       uses: actions/setup-python@v4
diff --git a/cmake/warnings.cmake b/cmake/warnings.cmake
index cddae999f..d76401f21 100644
--- a/cmake/warnings.cmake
+++ b/cmake/warnings.cmake
@@ -115,8 +115,13 @@ if(NOT COMMAND flamegpu_suppress_some_compiler_warnings)
             if(CMAKE_CUDA_COMPILER_VERSION VERSION_GREATER_EQUAL 11.6.0)
                 target_compile_definitions(${SSCW_TARGET} PRIVATE "__CDPRT_SUPPRESS_SYNC_DEPRECATION_WARNING")
             endif()
-        else()
-            # Linux specific warning suppressions
+        elseif(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
+            # Suppress unused-private-field warnings on Clang, which are falsely emitted in some cases where a private member is used in device code (i.e. ArrayMessage)
+            target_compile_options(${SSCW_TARGET} PRIVATE "$<$<COMPILE_LANGUAGE:CUDA>:SHELL:-Xcompiler -Wno-unused-private-field>")
+            target_compile_options(${SSCW_TARGET} PRIVATE "$<$<COMPILE_LANGUAGE:C,CXX>:-Wno-unused-private-field>")
+            # Suppress unused-but-set-variable which triggers on some device code.
+            target_compile_options(${SSCW_TARGET} PRIVATE "$<$<COMPILE_LANGUAGE:CUDA>:SHELL:-Xcompiler -Wno-unused-but-set-variable>")
+            target_compile_options(${SSCW_TARGET} PRIVATE "$<$<COMPILE_LANGUAGE:C,CXX>:-Wno-unused-but-set-variable>")
         endif()
         # Generic OS/host compiler warning suppressions
         # Ensure NVCC outputs warning numbers