[Bf-cycles] Cycles does not build with CUDA

[Robert Feld]

Hallo,

I tried to build cycles for Linux following the instructions from 
http://wiki.blender.org/index.php/Dev:2.5/Source/Render/Cycles/Building .

I was successful to build a blender version without CUDA support.

When I followed the instructions to build blender with CUDA support 
(including installation of the CUDA Toolkit), I encountered the 
following problem:

cmake ../cycles/ -DWITH_CYCLES_CUDA=ON -DCYCLES_CUDA=/usr/local/cuda 
-DCYCLES_CUDA_ARCH=sm_11

-- Could NOT find Spacenav (missing:  SPACENAV_LIBRARY SPACENAV_INCLUDE_DIR)
-- Unsupported CFLAG: -Wno-error=unused-but-set-variable
-- CUDA not found
-- Blender Skipping: (bf_collada;extern_openjpeg;extern_redcode)
-- rpmbuild NOT found. RPM generation will not be available
-- Configuring done
-- Generating done
-- Build files have been written to: <MY BUILD PATH>

When I inserted a debug printout in 
intern/cycles/cmake/external_libs.cmake I found that the variables that 
triggered the error have the following values:
-- CUDA includes = /usr/local/cuda/include
-- CUDA library = CUDA_LIBRARIES-NOTFOUND
-- CUDA nvcc = /usr/local/cuda/bin/nvcc

So for some reason CUDA_LIBRARIES seems to not have been set correctly.

My questions:
Do you have any idea, what goes wron here?
When I set the variables by hand, I get a version of blender built, that 
still seems to use only the CPU. So how can I determine once I have 
built blender, whether it actually uses my GPU?

The version I used is the current version from 
https://svn.blender.org/svnroot/bf-blender/branches/cycles

Kind regards,
Robert