CMake warnings: Policy CMP0028 is not set

[Tim Peeters]

I get a bunch of CMake warnings when I try to compile gallery-app:

tim@ubuntu:~/dev/r/gallery-app$ cmake .
-- Could NOT find Lcov (missing: LCOV_EXECUTABLE GENHTML_EXECUTABLE)
-- Could NOT find gcovr (missing: GCOVR_EXECUTABLE)
-- Autopilot tests enabled.
-- Configuring done
CMake Warning (dev) at src/CMakeLists.txt:51 (add_executable):
  Policy CMP0028 is not set: Double colon in target name means ALIAS or
  IMPORTED target. Run "cmake --help-policy CMP0028" for policy details.
  Use the cmake_policy command to set the policy and suppress this warning.

  Target "gallery-app" links to target "Qt5::Xml" but the target was not
  found. Perhaps a find_package() call is missing for an IMPORTED target, or
  an ALIAS target is missing?
This warning is for project developers. Use -Wno-dev to suppress it.

CMake Warning (dev) at src/medialoader/CMakeLists.txt:27 (add_library):
  Policy CMP0028 is not set: Double colon in target name means ALIAS or
  IMPORTED target. Run "cmake --help-policy CMP0028" for policy details.
  Use the cmake_policy command to set the policy and suppress this warning.

  Target "gallery-medialoader" links to target "Qt5::Widgets" but the target
  was not found. Perhaps a find_package() call is missing for an IMPORTED
  target, or an ALIAS target is missing?
This warning is for project developers. Use -Wno-dev to suppress it.

CMake Warning (dev) at tests/unittests/command-line-parser/CMakeLists.txt:12 (add_executable):
  Policy CMP0028 is not set: Double colon in target name means ALIAS or
  IMPORTED target. Run "cmake --help-policy CMP0028" for policy details.
  Use the cmake_policy command to set the policy and suppress this warning.

  Target "command-line-parser" links to target "Qt5::Widgets" but the target
  was not found. Perhaps a find_package() call is missing for an IMPORTED
  target, or an ALIAS target is missing?
This warning is for project developers. Use -Wno-dev to suppress it.

CMake Warning (dev) at tests/unittests/mediamonitor/CMakeLists.txt:18 (add_executable):
  Policy CMP0028 is not set: Double colon in target name means ALIAS or
  IMPORTED target. Run "cmake --help-policy CMP0028" for policy details.
  Use the cmake_policy command to set the policy and suppress this warning.

  Target "mediamonitor" links to target "Qt5::Widgets" but the target was not
  found. Perhaps a find_package() call is missing for an IMPORTED target, or
  an ALIAS target is missing?
This warning is for project developers. Use -Wno-dev to suppress it.

CMake Warning (dev) at tests/unittests/mediamonitor/CMakeLists.txt:18 (add_executable):
  Policy CMP0028 is not set: Double colon in target name means ALIAS or
  IMPORTED target. Run "cmake --help-policy CMP0028" for policy details.
  Use the cmake_policy command to set the policy and suppress this warning.

  Target "mediamonitor" links to target "Qt5::Widgets" but the target was not
  found. Perhaps a find_package() call is missing for an IMPORTED target, or
  an ALIAS target is missing?
This warning is for project developers. Use -Wno-dev to suppress it.

CMake Warning (dev) at tests/unittests/mediamonitor/CMakeLists.txt:18 (add_executable):
  Policy CMP0028 is not set: Double colon in target name means ALIAS or
  IMPORTED target. Run "cmake --help-policy CMP0028" for policy details.
  Use the cmake_policy command to set the policy and suppress this warning.

  Target "mediamonitor" links to target "Qt5::Widgets" but the target was not
  found. Perhaps a find_package() call is missing for an IMPORTED target, or
  an ALIAS target is missing?
This warning is for project developers. Use -Wno-dev to suppress it.

CMake Warning (dev) at tests/unittests/resource/CMakeLists.txt:12 (add_executable):
  Policy CMP0028 is not set: Double colon in target name means ALIAS or
  IMPORTED target. Run "cmake --help-policy CMP0028" for policy details.
  Use the cmake_policy command to set the policy and suppress this warning.

  Target "resource" links to target "Qt5::Widgets" but the target was not
  found. Perhaps a find_package() call is missing for an IMPORTED target, or
  an ALIAS target is missing?
This warning is for project developers. Use -Wno-dev to suppress it.

CMake Warning (dev) at tests/unittests/video/CMakeLists.txt:28 (add_executable):
  Policy CMP0028 is not set: Double colon in target name means ALIAS or
  IMPORTED target. Run "cmake --help-policy CMP0028" for policy details.
  Use the cmake_policy command to set the policy and suppress this warning.

  Target "video" links to target "Qt5::Xml" but the target was not found.
  Perhaps a find_package() call is missing for an IMPORTED target, or an
  ALIAS target is missing?
This warning is for project developers. Use -Wno-dev to suppress it.

-- Generating done
-- Build files have been written to: /home/tim/dev/r/gallery-app
tim@ubuntu:~/dev/r/gallery-app$

[Tim Peeters (tpeeters)]

I reproduced the bug with UITK staging r1612, and verified that the bug is not present in r1611, so it broke with this MR: https://code.launchpad.net/~zsombi/ubuntu-ui-toolkit/cppActionItem/+merge/268348

[Tim Peeters (tpeeters)]

sorry, I commented on the wrong bug! Ignore the comment above!