title: Do I have to build clang-11 from source on Ubuntu 18.04 to have OpenMP GPU target offload?
body: <p>I installed <code>clang-11</code> from <a href="https://apt.llvm.org/" rel="nofollow noreferrer">https://apt.llvm.org/</a> on Ubuntu 18.04 and I have OpenMP host device functionality working in my C++ test project, but <code>omp_get_num_devices()</code> returns <code>0</code>, even though I have Nvidia GPU and working CUDA 11 toolkit. Do I have to build a special version of Clang from source in order to get OpenMP GPU offload working, as described here: <a href="https://hpc-wiki.info/hpc/Building_LLVM/Clang_with_OpenMP_Offloading_to_NVIDIA_GPUs" rel="nofollow noreferrer">https://hpc-wiki.info/hpc/Building_LLVM/Clang_with_OpenMP_Offloading_to_NVIDIA_GPUs</a> ?</p>