请教CUDA启动返回错误码4问题

使用1080 GPU，VS2015
简化源码，如下

#include <stdio.h>
#include <cuda_runtime.h>
#include <helper_cuda.h>

__global__ void TestKernel()
{
    /*************** thread shared para setting *************************/
    for (int j = 0; j < 600; ++j) {
        printf("%d",j);
    }
}

int main()
{
    cudaError_t cudaStatus = cudaSuccess;

    TestKernel << < 20 , 256 >> >();

    /***** Check for any errors launching the kernel*******/
    cudaStatus = cudaGetLastError();
    if (cudaStatus != cudaSuccess) {
        fprintf(stderr, "\n\nTestKernel launch failed: %s\n", cudaGetErrorString(cudaStatus));
        return cudaStatus;
    }

    cudaStatus = cudaDeviceSynchronize();
    if (cudaStatus != cudaSuccess) {
        fprintf(stderr, "\n\ncudaDeviceSynchronize returned error code %d after launching TestKernel!\n", cudaStatus);
         return cudaStatus;
    }

    printf("end\n");
    getchar();
    return cudaStatus;
}



执行后报错返回错误码4，请问是什么问题？