PCL ROS and system install clashing?

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Compiling object_recognition_tabletop from source on Hydro throws lots of warning like this one:

CMake Warning at object_recognition_tabletop/src/db/CMakeLists.txt:2 (add_library):
  Cannot generate a safe runtime search path for target tabletop_db because files in some directories may conflict with libraries in implicit directories:

runtime library [libpcl_common.so.1.7] in /usr/lib may be hidden by files in:
  /opt/ros/hydro/lib
runtime library [libpcl_kdtree.so.1.7] in /usr/lib may be hidden by files in:
  /opt/ros/hydro/lib
runtime library [libpcl_octree.so.1.7] in /usr/lib may be hidden by files in:
  /opt/ros/hydro/lib
runtime library [libpcl_search.so.1.7] in /usr/lib may be hidden by files in:
  /opt/ros/hydro/lib
runtime library [libpcl_io.so.1.7] in /usr/lib may be hidden by files in:
  /opt/ros/hydro/lib
runtime library [libpcl_sample_consensus.so.1.7] in /usr/lib may be hidden by files in:
  /opt/ros/hydro/lib
runtime library [libpcl_filters.so.1.7] in /usr/lib may be hidden by files in:
  /opt/ros/hydro/lib
runtime library [libpcl_visualization.so.1.7] in /usr/lib may be hidden by files in:
  /opt/ros/hydro/lib
runtime library [libpcl_outofcore.so.1.7] in /usr/lib may be hidden by files in:
  /opt/ros/hydro/lib
runtime library [libpcl_features.so.1.7] in /usr/lib may be hidden by files in:
  /opt/ros/hydro/lib
runtime library [libpcl_segmentation.so.1.7] in /usr/lib may be hidden by files in:
  /opt/ros/hydro/lib
runtime library [libpcl_people.so.1.7] in /usr/lib may be hidden by files in:
  /opt/ros/hydro/lib
runtime library [libpcl_registration.so.1.7] in /usr/lib may be hidden by files in:
  /opt/ros/hydro/lib
runtime library [libpcl_recognition.so.1.7] in /usr/lib may be hidden by files in:
  /opt/ros/hydro/lib
runtime library [libpcl_keypoints.so.1.7] in /usr/lib may be hidden by files in:
  /opt/ros/hydro/lib
runtime library [libpcl_surface.so.1.7] in /usr/lib may be hidden by files in:
  /opt/ros/hydro/lib
runtime library [libpcl_tracking.so.1.7] in /usr/lib may be hidden by files in:
  /opt/ros/hydro/lib

Some of these libraries may not be found correctly.

What do I need to do to fix this?