Fix Rocm build issue (#642)

Fix cross-compiling issue. Add `target_compile_options` to make sure the
compile option is correct

Author: Binyang2014

CMakeLists.txt

@@ -91,7 +91,7 @@ elseif(MSCCLPP_USE_CUDA)
         list(APPEND MSCCLPP_GPU_ARCHS 120)
     endif()
 elseif(MSCCLPP_USE_ROCM)
-    set(CMAKE_HIP_ARCHITECTURES gfx90a gfx941 gfx942)
+    set(MSCCLPP_GPU_ARCHS gfx90a gfx941 gfx942)
 endif()
 
 message(STATUS "GPU architectures: ${MSCCLPP_GPU_ARCHS}")
@@ -146,6 +146,9 @@ if(MSCCLPP_USE_CUDA)
     target_compile_definitions(mscclpp_obj PRIVATE MSCCLPP_USE_CUDA)
 elseif(MSCCLPP_USE_ROCM)
     target_compile_definitions(mscclpp_obj PRIVATE MSCCLPP_USE_ROCM)
+    foreach(arch ${MSCCLPP_GPU_ARCHS})
+      target_compile_options(mscclpp_obj PRIVATE --offload-arch=${arch})
+    endforeach()
 endif()
 if(MSCCLPP_ENABLE_TRACE)
     target_compile_definitions(mscclpp_obj PRIVATE MSCCLPP_ENABLE_TRACE)

apps/nccl/CMakeLists.txt

@@ -19,6 +19,9 @@ if(MSCCLPP_USE_CUDA)
     target_compile_definitions(mscclpp_nccl_obj PRIVATE MSCCLPP_USE_CUDA)
 elseif(MSCCLPP_USE_ROCM)
     target_compile_definitions(mscclpp_nccl_obj PRIVATE MSCCLPP_USE_ROCM)
+    foreach(arch ${MSCCLPP_GPU_ARCHS})
+      target_compile_options(mscclpp_nccl_obj PRIVATE --offload-arch=${arch})
+    endforeach()
 endif()
 if(MSCCLPP_NPKIT_FLAGS)
     target_compile_definitions(mscclpp_nccl_obj PRIVATE ${MSCCLPP_NPKIT_FLAGS})