fix the debug flag for nvcc

cmake/cuda.cmake

@@ -167,12 +167,8 @@ select_nvcc_arch_flags(NVCC_FLAGS_EXTRA)
 list(APPEND CUDA_NVCC_FLAGS ${NVCC_FLAGS_EXTRA})
 message(STATUS "Added CUDA NVCC flags for: ${NVCC_FLAGS_EXTRA_readable}")
 
-if (WIN32)
-  set(CUDA_PROPAGATE_HOST_FLAGS ON)
-else (WIN32)
-  # Set C++11 support
-  set(CUDA_PROPAGATE_HOST_FLAGS OFF)
-endif (WIN32)
+# Set C++11 support
+set(CUDA_PROPAGATE_HOST_FLAGS OFF)
 
 # Release/Debug flags set by cmake. Such as -O3 -g -DNDEBUG etc.
 # So, don't set these flags here.
@@ -203,10 +199,12 @@ elseif(CMAKE_BUILD_TYPE  STREQUAL "MinSizeRel")
     list(APPEND CUDA_NVCC_FLAGS  ${CMAKE_CXX_FLAGS_RELEASE})
 endif()
 else(NOT WIN32)
-if(CMAKE_BUILD_TYPE STREQUAL "Release")
+if(CMAKE_BUILD_TYPE  STREQUAL "Debug")
+    list(APPEND CUDA_NVCC_FLAGS  "-g -lineinfo -G")
+elseif(CMAKE_BUILD_TYPE STREQUAL "Release")
   list(APPEND CUDA_NVCC_FLAGS "-O3 -DNDEBUG")
 else()
-  message(FATAL "Windows only support Release build now. Please set visual studio build type to Release, x64 build.")
+  message(FATAL "Windows only support Release or Debug build now. Please set visual studio build type to Release/Debug, x64 build.")
 endif()
 endif(NOT WIN32)