title: Got "recompile with -fPIC" error while the option is passed to the linker
body: <p>I am trying to compile <a href="https://github.com/spirit-code/VFRendering/tree/feature-pybind" rel="nofollow noreferrer">this git-repository</a> (branch: feature-pybind) with</p>
  
  <pre><code>option(BUILD_PYTHON_BINDINGS "Whether or not a binary python module should be built" ON)
  </code></pre>
  
  <p><a href="https://pastebin.com/ZUuNKn7a" rel="nofollow noreferrer">This is the output of the compilation</a>, but the interesting part is:</p>
  
  <pre><code>[100%] Linking CXX shared module pyVFRendering.cpython-34m.so
  /usr/bin/cmake -E cmake_link_script CMakeFiles/pyVFRendering.dir/link.txt --verbose=1
  /usr/bin/clang++  -fPIC   -shared  -o pyVFRendering.cpython-34m.so CMakeFiles/pyVFRendering.dir/python/vfrendering_bindings.cpp.o -flto libVFRendering.a qhull-prefix/src/qhull-build/libqhullcpp.a qhull-prefix/src/qhull-build/libqhullstatic_r.a 
  /usr/bin/ld: libVFRendering.a(ArrowRenderer.cxx.o): relocation R_X86_64_32S against `glad_glGenVertexArrays' can not be used when making a shared object; recompile with -fPIC
  libVFRendering.a: error adding symbols: Bad value
  clang-3.8: error: linker command failed with exit code 1 (use -v to see invocation)
  CMakeFiles/pyVFRendering.dir/build.make:97: recipe for target 'pyVFRendering.cpython-34m.so' failed
  make[2]: *** [pyVFRendering.cpython-34m.so] Error 1
  make[2]: Leaving directory '/home/matthias/VFRendering/build'
  CMakeFiles/Makefile2:68: recipe for target 'CMakeFiles/pyVFRendering.dir/all' failed
  make[1]: *** [CMakeFiles/pyVFRendering.dir/all] Error 2
  make[1]: Leaving directory '/home/matthias/VFRendering/build'
  Makefile:127: recipe for target 'all' failed
  make: *** [all] Error 2
  CC=clang: Kommando nicht gefunden    
  </code></pre>
  
  <p>Clearly I am passing the -fPIC flag to clang. I don't really understand the error message. What is ld complaining about? How can I fix this?</p>