Linux: undefined symbol problem when loading hdCycles.so

[sherholz]

Hi,

I am trying to run hdCycles under Ubuntu20.04 with USD20.08 and the current version of cycles (master branch).
Everything compiles without any problems but when I try to activate hdCycles in usdview I get the following error:

'Failed to load plugin 'hdCycles': /home/sherholz/USD20.08-local/plugin/usd/hdCycles.so: undefined symbol: _ZN3ccl9BVHParams15best_bvh_layoutENS_15KernelBVHLayoutEi in '/home/sherholz/USD20.08-local/plugin/usd/hdCycles.so''

As described in the documentation I compiled cycles with the:

-DCMAKE_POSITION_INDEPENDENT_CODE=ON

option turned on.
Plotting the linking command for hdCycles it looks like the corresponding cycles libraries are linked correctly:

[ 72%] Linking CXX shared library hdCycles.so
cd /home/sherholz/Develop/hdcycles/build/plugin/hdCycles && /usr/bin/cmake -E cmake_link_script CMakeFiles/hdCycles.dir/link.txt --verbose=1
/usr/bin/c++ -fPIC -std=c++11 -Wall -Wno-deprecated -Wno-deprecated-declarations -Wno-unused-local-typedefs -O3 -DNDEBUG -shared -Wl,-soname,hdCycles.so -o hdCycles.so CMakeFiles/hdCycles.dir/Mikktspace/mikktspace.c.o CMakeFiles/hdCycles.dir/basisCurves.cpp.o CMakeFiles/hdCycles.dir/camera.cpp.o CMakeFiles/hdCycles.dir/instancer.cpp.o CMakeFiles/hdCycles.dir/light.cpp.o CMakeFiles/hdCycles.dir/material.cpp.o CMakeFiles/hdCycles.dir/mesh.cpp.o CMakeFiles/hdCycles.dir/points.cpp.o CMakeFiles/hdCycles.dir/renderDelegate.cpp.o CMakeFiles/hdCycles.dir/rendererPlugin.cpp.o CMakeFiles/hdCycles.dir/renderPass.cpp.o CMakeFiles/hdCycles.dir/renderParam.cpp.o CMakeFiles/hdCycles.dir/config.cpp.o CMakeFiles/hdCycles.dir/renderBuffer.cpp.o CMakeFiles/hdCycles.dir/utils.cpp.o -Wl,-rpath,/home/sherholz/USD20.08-local/lib::::::::::::::::::...
...
...
/home/sherholz/Develop/cycles/build/lib/libcycles_bvh.a /home/sherholz/Develop/cycles/build/lib/libcycles_device.a /home/sherholz/Develop/cycles/build/lib/libcycles_graph.a /home/sherholz/Develop/cycles/build/lib/libcycles_kernel.a /home/sherholz/Develop/cycles/build/lib/libcycles_render.a /home/sherholz/Develop/cycles/build/lib/libcycles_subd.a /home/sherholz/Develop/cycles/build/lib/libcycles_util.a /home/sherholz/Develop/cycles/build/lib/libextern_clew.a /home/sherholz/Develop/cycles/build/lib/libextern_cuew.a /home/sherholz/Develop/cycles/build/lib/libextern_numaapi.a
...
...

Any ideas or am I missing something essential?

[sherholz]

Hi,
I solved the problem by rearranging the order in which the cycles libraries are linked in.
The cycles_bvh library was linked first but the functions provided by it are used by a later library (i.e., cycles_render).

I filed a pull request with a patch for that problem (#5)