Thank you for the above query. I'll take a look at the sample code and get back to you shortly.
By the way, the pre-built sample binary ("DeviceEnqueueBFS.exe" inside "\opencl\bin" folder) seems working fine on my AMD laptop.
After reading the spec, it looks like compiler can enforce the pipe access qualifier when a pipe is passed to a child kernel. So, the above error is not unexpected. In fact, our new compiler (clang based LC compiler) also reports a similar error for this sample. The HSAIL compiler tool-chain, which I used earlier to test the sample binary, seems to permit it.
yeh, agree with you that this issue is compiler related. And i will have a look around at "HSAIL compiler tool-chain". Thanks for you time man.