message: In the CMake build system, use CMAKE_SHARED_LIBRARY_CXX_FLAGS to
  get the PIC compiler flag instead of the hardcoded '-fPIC' value.
  Suggested by:
diff: @@ -729,8 +729,7 @@ function(mfem_export_mk_files)
  set(MFEM_INCFLAGS "-I\$(MFEM_INC_DIR) \$(MFEM_TPLFLAGS)")
  set(MFEM_PICFLAG "")
  if (BUILD_SHARED_LIBS)
  - # TODO: How do we get the PIC from CMake?
  - set(MFEM_PICFLAG "-fPIC")
  + set(MFEM_PICFLAG "${CMAKE_SHARED_LIBRARY_CXX_FLAGS}")
  endif()
  set(MFEM_FLAGS "\$(MFEM_CPPFLAGS) \$(MFEM_CXXFLAGS) \$(MFEM_INCFLAGS)")
  # TPL link flags: set below
  