Error: “incorrect inclusion of a cudart header file”

If you receive this error while compiling a CUDA program, it means that you have included a CUDA header file containing CUDA specific qualifiers (such as __device__)  in a *.cpp file.

CUDA header files with such qualifiers should ONLY be included in *.cu files.

This happened to me when I had #inlcude <common_functions.h> in my *.cpp file. Note that having this in a header file that will be linked to a *.cpp file will also result in the same error.