CUDA_ARCHITECTURES is empty for target “main”.

Today, I got an error below while I was compiling my CUDA program. It was simple mistake.

I forgot to add code below in my CMakeLists.txt. Add below line after “cmake_minimum_required(VERSION 3.10).” The error message above was gone.

if(NOT DEFINED CMAKE_CUDA_ARCHITECTURES)
  set(CMAKE_CUDA_ARCHITECTURES 75)
endif()