googletest 1.8.0-2 (on zesty) breaks existing builds [add_library cannot create target "gmock" ...]

[Michi Henning]

After upgrading to 1.8.0-2 (from 1.7.0-4), our previously-working builds break:

CMake Error at /usr/src/googletest/googletest/cmake/internal_utils.cmake:149 (add_library):
   add_library cannot create target "gmock" because another target with the
   same name already exists. The existing target is a static library created
   in source directory "/usr/src/googletest/googlemock". See documentation
   for policy CMP0002 for more details.
 Call Stack (most recent call first):
   /usr/src/googletest/googletest/cmake/internal_utils.cmake:172 (cxx_library_with_type)
   /usr/src/gmock/CMakeLists.txt:84 (cxx_library)

 CMake Error at /usr/src/googletest/googletest/cmake/internal_utils.cmake:149 (add_library):
   add_library cannot create target "gmock_main" because another target with
   the same name already exists. The existing target is a static library
   created in source directory "/usr/src/googletest/googlemock". See
   documentation for policy CMP0002 for more details.
 Call Stack (most recent call first):
   /usr/src/googletest/googletest/cmake/internal_utils.cmake:172 (cxx_library_with_type)
   /usr/src/gmock/CMakeLists.txt:89 (cxx_library)

 CMake Error at /usr/src/gmock/CMakeLists.txt:106 (install):
   install TARGETS given target "gmock" which does not exist in this
   directory.

The CMakeLists.txt in our project that triggers this error does this:

set(old_cxx_flags ${CMAKE_CXX_FLAGS})
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -g -Wno-old-style-cast -Wno-missing-field-initializers")
find_package(GMock)
set(CMAKE_CXX_FLAGS ${old_cxx_flags})

This used to work fine, but no breaks on zesty.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Daniel van Vugt (vanvugt)]

WORKAROUND:

1. Uninstall 'googletest' and friends.
2. Install the previous version:
https://launchpad.net/ubuntu/+archive/primary/+files/libgtest-dev_1.7.0-4ubuntu1_amd64.deb
https://launchpad.net/ubuntu/+archive/primary/+files/google-mock_1.7.0-18092013-2.1_amd64.deb

[Michi Henning (michihenning)]

Here is a cmake-extras change that deals with the broken googletest:

https://code.launchpad.net/~michihenning/cmake-extras/gtest-fixes/+merge/311565

[Michi Henning (michihenning)]

Fix is in silo 2225.

[Launchpad Janitor (janitor)]

This bug was fixed in the package cmake-extras - 0.7+17.04.20161123.5-0ubuntu1

---------------
cmake-extras (0.7+17.04.20161123.5-0ubuntu1) zesty; urgency=medium

  * Fixes for gtest 1.8.0. (LP: #1644062) (LP: #1644062)

 -- Michi Henning <email address hidden> Wed, 23 Nov 2016 06:25:33 +0000

[Daniel van Vugt (vanvugt)]

Hmm, looks like Mir won't benefit from that fix (doesn't use cmake-extras). Another fix will be required still.

[Michi Henning (michihenning)]

The fix for cmake-extras allows the builds to complete, but it still doesn't work. The problem now is that gtest install a pile of stuff in the install directory and, when it comes to creating the packages, the debian installation fails because of the --fail-missing; there are loads of files in the install dir now that are not picked up by the .install files. Sigh...

[Michi Henning (michihenning)]

If you figure out how to fix this for Mir, I'd like know what you did. The other avenue I tried was ExternalProject_Add, but I didn't get very far with that either because it seems that the gtest cmake files don't honour the INSTALL_DIR variable.

[Daniel van Vugt (vanvugt)]

Also reported upstream:
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=844843

[Mir CI Bot (mir-ci-bot)]

Fix committed into lp:mir at revision None, scheduled for release in mir, milestone 0.26.0

[Daniel van Vugt (vanvugt)]

Probably "Won't Fix" the googletest package itself, since this is its original form from Debian and we can work around it.

[Daniel van Vugt (vanvugt)]

Fix committed to lp:mir/0.25 at revision 3819, scheduled for release in Mir 0.25.1 (or 0.25.0 ... not sure which one yet).

[Launchpad Janitor (janitor)]

This bug was fixed in the package content-hub - 0.2+17.04.20161128-0ubuntu1

---------------
content-hub (0.2+17.04.20161128-0ubuntu1) zesty; urgency=medium

  * Fix build failure on zesty due to googletest 1.8. Also refactored
    tests/acceptance-tests/CMakeLists.txt to make adding tests less
    cumbersome. (LP: #1644062)

 -- Ken VanDine <email address hidden> Mon, 28 Nov 2016 17:39:58 +0000

[Launchpad Janitor (janitor)]

This bug was fixed in the package unity - 7.5.0+17.04.20161130-0ubuntu1

---------------
unity (7.5.0+17.04.20161130-0ubuntu1) zesty; urgency=medium

  [ Kai-Heng Feng ]
  * UnitySettings: If scale-factor is not set, find and set right scale
    for HiDPI displays.

  [ Marco Trevisan (Treviño) ]
  * CMakeLists.txt: add support to compile with GTest 1.8 (LP: #1644062)
  * UnityScreen: toggle gestures recognition on lock (LP: #1645507)

 -- Marco Trevisan (Treviño) <[e-mail]> Wed, 30 Nov 2016 11:06:58 +0000

[Launchpad Janitor (janitor)]

This bug was fixed in the package mir - 0.25.0+17.04.20161203-0ubuntu1

---------------
mir (0.25.0+17.04.20161203-0ubuntu1) zesty; urgency=medium

  * New upstream release 0.25.0 (https://launchpad.net/mir/+milestone/0.25.0)
    - ABI summary:
      . mirclient ABI unchanged at 9
      . mirserver ABI bumped to 42
      . mircommon ABI bumped to 7
      . mirplatform ABI bumped to 14
      . mirprotobuf ABI unchanged at 3
      . mirplatformgraphics ABI bumped to 11
      . mirclientplatform ABI unchanged at 5
      . mirinputplatform ABI bumped to 6
      . mircore ABI added, at version 1
    - Enhancements:
      . Added pointer confinement support
      . Identify Raspberry Pi output types correctly
      . Added dead key and compose key support
      . Added gamma support for KMS hardware
      . Added yakkety and zesty gcc-6 support
      . Added surface passthrough support for fullscreen clients of nested
        servers
      . Introduced a new library `libmircore'
      . Began migrating from Protobuf to Cap'n Proto starting with events
      . Began support for VirtualBox (servers now start instead of crashing
        but full support for GL clients is still missing)
      . Began support for high precision frame timing, implemented for the
        KMS, Android and X11 backends so far
      . Added --display-report support for the X11 backend
      . Improved reliability of `mirvanity' latency test tool
      . Moved to using the CSS cursor naming scheme internally, although
        the old symbolic indentifiers remain unchanged and still work
      . Added refresh rate to MirSurfaceOutputEvent
      . Many improvements to automated test quality and coverage
      . Smoother desktop zoom using mir_proving_server (Super + two fingers)
    - Bugs fixed:
      . FTBFS On Zesty: invalid use of
        'struct native_handle' (LP: #1638774)
      . libmirclient-debug-extension-dev install debug/surface.h
        twice (LP: #1639153)
      . Mir crashes on virtual box drmModeCrtcSetGamma
        Function not implemented (LP: #1638220)
      . Flickering in mir_demo_client_multistream (LP: #1635273)
      . Camera apps (camera & vanity) never exit (LP: #1635010)
      . Clients cannot connect when MIR_SOCKET="" (LP: #1634508)
      . mirtest-dev packaging fails to sepcify boost depends (LP: #1633537)
      . cursor.h is unclear about mir_diagonal_resize_* (LP: #1626924)
      . Inconsistent underscores in cursor names (LP: #1632617)
      . [regression] Accidental libmircommon.so.6 break (LP: #1617865)
      . [regression] mir demo server fails to start with mx4 (LP: #1615703)
      . [regression] Trust prompt now shown when starting camera (LP: #1612256)
      . [regression] make abi-check fails to build (LP: #1626866)
      . Nested servers prevent overlays or fullscreen bypass (LP: #1262116)
      . Failed to get PRIME fd from gbm bo (LP: #1607812)
      . Mir-on-X is difficult to use on 1366x768 laptop (LP: #1590959)
      . Remove useless message 'Surface 0 DPI' in demos (LP: #1559831)
      . Mir fails to cross-build with newer sbuild (LP: #1628507)
      . Infinite loop in AbstractShell::focus_next_session (LP: #1625401)
      . Dest...