Pointers values in DLL couldn't be copied from host to device cudaMemcpy() couldn't copy hos

Accelerated Computing CUDA CUDA Programming and Performance
1

I have created DLL which is CUDA application and it is linked with C++ exe app. When __declspec function is called, cudaMemcpy() function in DLL doesn’t copy values from host memory to device. They are double type pointers, and no error is reported, neither for cudaMemcpy function nor for cudaMalloc.
Also, local variables for DLL couldn’t be watched.