I am working on blender GPGPU renderer and I found that Intel OpenCL hangs (NVidia works fine with same code).

It isn't even computing yet, Intel OpenCL 1.5 hangs in the call to clBuildProgram.

intelocl.dll C:\\Program Files (x86)\\Intel\\OpenCL SDK\\1.5\\bin\\x64\\intelocl.dll 000007FEF95F0000-000007FEF9694000

xor ecx,ecx/call qword ptr [7FEF963B068h] is a call to Sleep(0)

This is the infinite spin loop:

000007FEF96140B0 BA 01 00 00 00 mov edx,1 000007FEF96140B5 33 C9 xor ecx,ecx 000007FEF96140B7 FF 15 AB 6F 02 00 call qword ptr [7FEF963B068h] (call to kernel32!Sleep) 000007FEF96140BD 33 C0 xor eax,eax 000007FEF96140BF F0 0F B1 BB 8C 00 00 00 lock cmpxchg dword ptr [rbx+8Ch],edi 000007FEF96140C7 83 F8 05 cmp eax,5 000007FEF96140CA 75 E4 jne 000007FEF96140B0

This pegs the core to 100%.

It never finishes, this thread just eats infinite CPU and clBuildProgram never returns.

This is the call stack:

KernelBase.dll!SleepEx()
intelocl.dll!000007fef96140bd()
[Frames below may be incorrect and/or missing, no symbols loaded for intelocl.dll]
intelocl.dll!000007fef960d0d8()
intelocl.dll!000007fef960cf13()
intelocl.dll!000007fef9609673()
intelocl.dll!000007fef95ff1bf()
intelocl.dll!000007fef95f65ed()
OpenCL.dll!000007fef9d71a9f()
>
blender.exe!ccl::OpenCLDevice::build_kernel(const
std::basic_string,std::allocator
> & kernel_path="") Line 398 + 0x32 bytes C++

blender.exe!ccl::OpenCLDevice::compile_kernel(const
std::basic_string,std::allocator
> & kernel_path={...}, const
std::basic_string,std::allocator
> & kernel_md5="pE@") Line 441 + 0xb bytes C++
blender.exe!ccl::OpenCLDevice::load_kernels(bool experimental=true) Line 498 + 0xa bytes C++
blender.exe!ccl::Session::run() Line 421 + 0x13 bytes C++
blender.exe!ccl::thread::run(void * arg=0x0000000000000000) Line 58 C++

Another thread throws an access violation exception:

000007FEE9800E29 80 7A 08 05 cmp byte ptr [rdx+8],5

rdx+8 = 0x0000000145962fb0

Call stack:

> OclCpuBackEnd.dll!000007fee9800e29()
[Frames below may be incorrect and/or missing, no symbols loaded for OclCpuBackEnd.dll]
OclCpuBackEnd.dll!000007fee9800dcb()
OclCpuBackEnd.dll!000007fee97fe7c4()
OclCpuBackEnd.dll!000007fee939a95d()
OclCpuBackEnd.dll!000007fee939a580()
OclCpuBackEnd.dll!000007fee939a270()
OclCpuBackEnd.dll!000007fee97de441()
OclCpuBackEnd.dll!000007fee939b1c0()
OclCpuBackEnd.dll!000007fee939ba90()
OclCpuBackEnd.dll!000007fee9271248()
OclCpuBackEnd.dll!000007fee926f149()
cpu_device.dll!000007fef12c8d52()
task_executor.dll!000007fef98a1fe3()
task_executor.dll!000007fef98a286d()
tbb.dll!0000000017f4a3b5()
tbb.dll!0000000017f48e8f()
tbb.dll!0000000017f47ba4()
tbb.dll!0000000017f45969()
msvcr90.dll!_endthreadex() + 0x47 bytes
msvcr90.dll!_endthreadex() + 0xe8 bytes
kernel32.dll!BaseThreadInitThunk() + 0xd bytes
ntdll.dll!RtlUserThreadStart() + 0x21 bytes

OclCpuBackEnd.dll C:\\Program Files (x86)\\Intel\\OpenCL SDK\\1.5\\bin\\x64\\OclCpuBackEnd.dll 1, 5, 0, 15293 9/14/2011 7:59 AM 000007FEE9260000-000007FEE9B93000

The program is running with pageheap enabled. (Enabled with debugging tools for windows gflags.exe)