CMake linker warning: lib<foo>.so.<v1> may conflict with lib<foo>.so.<v2>

edit

I am getting a ton of linker warnings when building a catkin package, and I don't know whether they are dangerous or not. Things seem to be working fine, but want to make sure that I'm not setting myself up for future failure.

Could anyone shed some light on the nature of these errors, or do they seem benign?

CMake Warning (dev) at PID/CMakeLists.txt:73 (add_dependencies):
  Policy CMP0046 is not set: Error on non-existent dependency in
  add_dependencies.  Run "cmake --help-policy CMP0046" for policy details.
  Use the cmake_policy command to set the policy and suppress this warning.

  The dependency target "diagnostic_updater" of target "controller" does not
  exist.
This warning is for project developers.  Use -Wno-dev to suppress it.

CMake Warning (dev) at PID/CMakeLists.txt:73 (add_dependencies):
  Policy CMP0046 is not set: Error on non-existent dependency in
  add_dependencies.  Run "cmake --help-policy CMP0046" for policy details.
  Use the cmake_policy command to set the policy and suppress this warning.

  The dependency target "dynamic_reconfigure" of target "controller" does not
  exist.
This warning is for project developers.  Use -Wno-dev to suppress it.

CMake Warning (dev) at PID/CMakeLists.txt:87 (add_dependencies):
  Policy CMP0046 is not set: Error on non-existent dependency in
  add_dependencies.  Run "cmake --help-policy CMP0046" for policy details.
  Use the cmake_policy command to set the policy and suppress this warning.

  The dependency target "diagnostic_updater" of target "mvp_controller" does
  not exist.
This warning is for project developers.  Use -Wno-dev to suppress it.

CMake Warning (dev) at PID/CMakeLists.txt:87 (add_dependencies):
  Policy CMP0046 is not set: Error on non-existent dependency in
  add_dependencies.  Run "cmake --help-policy CMP0046" for policy details.
  Use the cmake_policy command to set the policy and suppress this warning.

  The dependency target "dynamic_reconfigure" of target "mvp_controller" does
  not exist.
This warning is for project developers.  Use -Wno-dev to suppress it.

CMake Warning (dev) at PID/CMakeLists.txt:74 (add_dependencies):
  Policy CMP0046 is not set: Error on non-existent dependency in
  add_dependencies.  Run "cmake --help-policy CMP0046" for policy details.
  Use the cmake_policy command to set the policy and suppress this warning.

  The dependency target "diagnostic_updater" of target "plant_sim" does not
  exist.
This warning is for project developers.  Use -Wno-dev to suppress it.

CMake Warning (dev) at PID/CMakeLists.txt:74 (add_dependencies):
  Policy CMP0046 is not set: Error on non-existent dependency in
  add_dependencies.  Run "cmake --help-policy CMP0046" for policy details.
  Use the cmake_policy command to set the policy and suppress this warning.

  The dependency target "dynamic_reconfigure" of target "plant_sim" does not
  exist.
This warning is for project developers.  Use -Wno-dev to suppress it.

CMake Warning (dev) at PID/CMakeLists.txt:75 (add_dependencies):
  Policy CMP0046 is not set: Error on non-existent dependency in
  add_dependencies.  Run "cmake --help-policy CMP0046" for policy details.
  Use the cmake_policy command to set the policy and suppress this warning.

  The dependency target "diagnostic_updater" of target "setpoint_node" does
  not exist.
This warning is for project developers.  Use -Wno-dev to suppress it.

CMake Warning (dev) at PID/CMakeLists.txt:75 (add_dependencies):
  Policy CMP0046 is not set: Error on non-existent dependency in ...