Build fails: undefined reference

[alphapapa]

I'm on Ubuntu 14.04.

$ git clone --recursive https://github.com/QMatrixClient/Quaternion.git
$ git submodule init
$ git submodule update
$ mkdir build_dir && cd build_dir
$ cmake ..
$ cmake --build . --target all
...
lib/libqmatrixclient.a(room.cpp.o): In function `QMatrixClient::operator<<(QDebug, QMatrixClient::Event::Type)':
/home/me/src/misc/Quaternion/lib/events/event.h:75: undefined reference to `QMatrixClient::Event::staticMetaObject'
/home/me/src/misc/Quaternion/lib/events/event.h:75: undefined reference to `QMatrixClient::Event::staticMetaObject'
lib/libqmatrixclient.a(roommessageevent.cpp.o): In function `QMatrixClient::operator<<(QDebug, QMatrixClient::RoomMessageEvent::MsgType)':
/home/me/src/misc/Quaternion/lib/events/roommessageevent.h:68: undefined reference to `QMatrixClient::RoomMessageEvent::staticMetaObject'
/home/me/src/misc/Quaternion/lib/events/roommessageevent.h:68: undefined reference to `QMatrixClient::Event::staticMetaObject'

Thanks.

[KitsuneRal]

Judging by the looks of it, there's something wrong with REGISTER_ENUM macro. I cannot reproduce the issue though. Do you have Qt4 include files around, by any chance? What versions did cmake .. report?

[alphapapa]

Do you have Qt4 include files around, by any chance?

I do have the libqt4-dev package installed. I build KDE/Qt4 apps occasionally.

What versions did cmake .. report?

$ cmake ..
-- The CXX compiler identification is GNU 4.8.4
-- Check for working CXX compiler: /usr/bin/c++
-- Check for working CXX compiler: /usr/bin/c++ -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- 
-- =============================================================================
--                           Quaternion Build Information
-- =============================================================================
-- Build type: Debug
-- Using compiler: GNU 4.8.4
-- Using Qt 5.2.1 at /usr
-- Quaternion install prefix: /usr/local
-- =============================================================================
-- 
-- The C compiler identification is GNU 4.8.4
-- Check for working C compiler: /usr/bin/cc
-- Check for working C compiler: /usr/bin/cc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- 
-- =============================================================================
--                        libqmatrixclient Build Information
-- =============================================================================
-- Build type: Debug
-- Using compiler: GNU 4.8.4
-- Using Qt 5.2.1 at /usr
-- =============================================================================
-- 
CMake Warning (dev) at /usr/lib/x86_64-linux-gnu/cmake/Qt5Core/Qt5CoreMacros.cmake:224 (configure_file):
  configure_file called with unknown argument(s):

   COPY_ONLY

Call Stack (most recent call first):
  CMakeLists.txt:88 (QT5_ADD_RESOURCES)
This warning is for project developers.  Use -Wno-dev to suppress it.

-- Configuring done
-- Generating done
-- Build files have been written to: /home/me/src/misc/Quaternion/build_dir

Thanks.

[alphapapa]

I was able to build https://github.com/mujx/nheko following its instructions to use Qt 5.8, so I tried building Quaternion with Qt 5.8 and it worked.

I would really prefer to build it with the distro Qt, because I had to install 5.8 from a PPA that nheko recommends, but which I don't know anything about. But I don't know if it is feasible for you to fix it with 5.2.1. If not, maybe the minimum version should be increased in the instructions.

Thanks for your help.

[alphapapa]

Well, I say it worked: it appeared to work, but it doesn't run:

$ quaternion
quaternion: /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5: no version information available (required by quaternion)
quaternion: /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5: no version information available (required by quaternion)
quaternion: /usr/lib/x86_64-linux-gnu/libQt5Network.so.5: no version information available (required by quaternion)
quaternion: /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5: no version information available (required by quaternion)
quaternion: /usr/lib/x86_64-linux-gnu/libQt5Core.so.5: no version information available (required by quaternion)
quaternion: /usr/lib/x86_64-linux-gnu/libQt5Core.so.5: no version information available (required by quaternion)
quaternion: /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5: no version information available (required by quaternion)
quaternion: relocation error: quaternion: symbol qt_version_tag, version Qt_5.8 not defined in file libQt5Core.so.5 with link time reference

It looks like it's trying to use the distro Qt instead of the PPA package that installed into /opt/qt58.

I built it like this:

$ cd build_dir
$ cmake -DCMAKE_PREFIX_PATH=/opt/qt58/ ..
$ cmake --build . --target all

[alphapapa]

I remembered something from the PPA description:

Source /opt/qt58/bin/qt58-env.sh to set the correct environment.

Using that (it also works as a wrapper script), it seems to work!

[alphapapa]

Well, I say it seems to work, but no messages are displayed. I see in the readme that it is likely a problem with QtQuick, and I don't see a 5.8 version of that in the PPA I'm using for Qt 5.8, so I guess I'm stuck.

[KitsuneRal]

In fact, libqmatrixclient should build just fine with Qt 5.2.1, and the CI environment ensures that on a daily basis. So there's clearly some trouble with your environment. Just to check, can you remove libqt4-dev for a minute and try building with the stock Trusty Qt again? We'll at least localise the trouble then.

[KitsuneRal]

And yes, no messages mean that Quaternion could not get a hold of Qt Quick (+plugins - as mentioned in README.md). Let's figure what's wrong with the Qt 5.2.1 environment.

[alphapapa]

Ok, I removed libqt4-dev and rebuilt, and the build completed without errors. Then I installed and ran it. It runs, and I can send messages, but still no messages are displayed. I see this in the console:

$ quaternion
Debug:  false 
qrc:///qml/chat.qml:5:1: module "Qt.labs.settings" is not installed 
--- Show time! 
QXcbWindow: Unhandled client message: "_QTCURVE_ACTIVE_WINDOW_" 
libqmatrixclient.jobs: "MediaThumbnailJob" status 104 : "Error downloading https://matrix.org/_matrix/media/v1/thumbnail/?width=16&height=16&method=scale - server replied: Not Found" 
Connected to room "!nnldzrRaEKzhEnLmjB:matrix.org" as "@alphapapa:matrix.org" 
2 user(s) in the room 
libqmatrixclient.jobs: "MediaThumbnailJob" status 104 : "Error downloading https://matrix.org/_matrix/media/v1/thumbnail/?width=30&height=30&method=scale - server replied: Not Found" 
libqmatrixclient.jobs: "MediaThumbnailJob" status 104 : "Error downloading https://matrix.org/_matrix/media/v1/thumbnail/?width=25&height=25&method=scale - server replied: Not Found" 
QXcbWindow: Unhandled client message: "_QTCURVE_ACTIVE_WINDOW_"

Thanks.

[alphapapa]

Ok, fixed that by installing the qtdeclarative5-settings-plugin package. I guess that should be added to the prereqs list. Seems to be working pretty well now!

[KitsuneRal]

Uhm, that is a good catch indeed. Quaternion does use Qt.lab.settings these days but the respective plugin is not mentioned in README.md. Thanks for finding out!

[alphapapa]

You might also want to mention that libqt4-dev and/or other Qt4-related dev packages may cause conflicts in the build process.

[KitsuneRal]

Mentioned that, thank you; and in the end removed Qt.labs.Settings usage entirely.