How to use double in kernel function?

Discussion created by Fuxianjun on Jun 22, 2010
Latest reply on Jun 23, 2010 by Fuxianjun

I read section 9.3 of OpenCL specification,how can I use double in a kernel function? I tried to add "#pragma OPENCL EXTENSION cl_khr_fp64:enable"on the top of kernel function,but my program failed to compile,what can I do ?
By the way, I used "clGetDeviceInfo" to query"CL_DEVICE_PREFERRED_VECTOR_WIDTH_DOUBLE", it returned 0,does it means my GPU support double precision or not ?