Installing libclc on Ubuntu 14.04 LTS

libclc is needed for using Clang with OpenCL. See here for more details. Unfortunately it requires LLVM to be 3.7 or higher, while Ubuntu 14.04 only has up to 3.6.

Make sure you don't have LLVM installed before proceeding.To get around this you first have to get LLVM 3.7 by adding this line:

deb http://llvm.org/apt/precise/ llvm-toolchain-precise-3.7 main

 to this file:

/etc/apt/sources.list.d/llvm.list

I used nano. The original instructions using output redirection didn't work for me. You can find the address for other versions of Ubuntu or LLVM here. Now install llvm-3.7 and clang-3.7

sudo apt-get install llvm-3.7 clang-3.7

It will complain that it can't verify the source, but we added the source so go ahead and ignore it. Next get libclc if you don't already have it:

git clone http://llvm.org/git/libclc.git

Go through the readme and use llvm-config-3.7 instead of llvm-config. You may get an error like so:

/usr/bin/ld: cannot find -ledit

In this case just install libedit:

 sudo apt-get install libedit-dev

 However I still got many warnings of the following type:

WARNING: Linking two modules of different data layouts: 'amdgcn--/lib/image/write_image_impl.ll.tahiti.bc' is '' whereas 'llvm-link' is 'e-p:32:32-p1:64:64-p2:64:64-p3:32:32-p4:64:64-p5:32:32-p24:64:64-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128-v192:256-v256:256-v512:512-v1024:1024-v2048:2048-n32:64'

A quick google search returned nothing. Because the data layout of the first module is empty I'm going to proceed with the assumption that I can ignore this.