Comment 119 for bug 1129409

That is the problem: There should be only one loader but there are two of them. fglrx at least (I ignore what is the case for nvidia) provides its own at /usr/lib/libOpenCL.so.1 and this conflicts with the one by ocl-icd-libopencl1 that goes to /usr/lib/x86_64-linux-gnu/libOpenCL.so.1. Both are the same version and the latter takes precedence, which is not what some software expects.