Protobuf version conflicts with Qt

问题:

I'm trying to use protobufs v 3.3.2 with Qt 5.9.1. This works with some Qt applications, but only if they are command line programs. Once I create a GUI application with Qt and protobufs, I get this error:

[libprotobuf FATAL /home/mkraus/Documents/dev/star385/build/linux-desktop-debug-libs/protobuf/src/src/google/protobuf/stubs/common.cc:78] This program was compiled against version 2.6.1 of the Protocol Buffer runtime library, which is not compatible with the installed version (3.3.2). Contact the program author for an update. If you compiled the program yourself, make sure that your headers are from the same version of Protocol Buffers as your link-time library. (Version verification failed in "/build/mir-ui6vjS/mir-0.26.3+16.04.20170605/obj-x86_64-linux-gnu/src/protobuf/mir_protobuf.pb.cc".)

I should clarify that my part of the code is certainly using version 3.3.2 (I'm downloading and compiling protobufs from the git sources and statically linking). Look at the stack trace below to see that something that Qt is referencing is causing a protobuf version mismatch.

I'm developing on Ubuntu 16.04 and using the default desktop environment (Unity).

Work-Arounds

My troubleshooting has revealed these symptoms and work-arounds:

• Use KDE / KUbuntu. Changing the desktop environment when logging in completely avoids the version mismatch issue.

• Run the Qt application with -platform eglfs. This runs the application in full-screen mode using OpenGL. The program runs, but the window size is incorrect. When using the -platform eglfs option, it works even in Unity, but without this option, it gives me the above error.

• Any Qt application that is a command-line only application (using QCoreApplication instead of QGuiApplication) can use protobufs 3.3.2. Changing the same app to use a GUI causes the version mismatch issue.

Questions

How can I use protobufs 3.3.2 with Qt GUI applications, and also not be dependent on what desktop environment is in use? Is it Qt that is using the version 2.6.1 of protobufs, and if so, is it feasible to compile Qt to use protobufs 3.3.2?

Debug Info

Here is a stack trace (the program crashes almost immediately upon starting):

terminate called after throwing an instance of 'google::protobuf::FatalException'   what():  This program was compiled against version 2.6.1 of the Protocol Buffer runtime library, which is not compatible with the installed version (3.3.2).  Contact the program author for an update.  If you compiled the program yourself, make sure that your headers are from the same version of Protocol Buffers as your link-time library.  (Version verification failed in "/build/mir-ui6vjS/mir-0.26.3+16.04.20170605/obj-x86_64-linux-gnu/src/protobuf/mir_protobuf.pb.cc".)  Thread 1 "scan" received signal SIGABRT, Aborted. 0x00007ffff4dff428 in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:54 54  ../sysdeps/unix/sysv/linux/raise.c: No such file or directory. (gdb) bt #0  0x00007ffff4dff428 in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:54 #1  0x00007ffff4e0102a in __GI_abort () at abort.c:89 #2  0x00007ffff543984d in __gnu_cxx::__verbose_terminate_handler() () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6 #3  0x00007ffff54376b6 in ?? () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6 #4  0x00007ffff5437701 in std::terminate() () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6 #5  0x00007ffff5437919 in __cxa_throw () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6 #6  0x0000000000603e0a in google::protobuf::internal::LogMessage::Finish (this=0x7fffffffc250)     at /home/mkraus/Documents/dev/star385/build/linux-desktop-debug-libs/protobuf/src/src/google/protobuf/stubs/common.cc:268 #7  0x0000000000603e5a in google::protobuf::internal::LogFinisher::operator= (this=0x7fffffffc20f, other=...)     at /home/mkraus/Documents/dev/star385/build/linux-desktop-debug-libs/protobuf/src/src/google/protobuf/stubs/common.cc:276 #8  0x0000000000603171 in google::protobuf::internal::VerifyVersion (headerVersion=2006001, minLibraryVersion=2006000,      filename=0x7fffde80aec0 "/build/mir-ui6vjS/mir-0.26.3+16.04.20170605/obj-x86_64-linux-gnu/src/protobuf/mir_protobuf.pb.cc")     at /home/mkraus/Documents/dev/star385/build/linux-desktop-debug-libs/protobuf/src/src/google/protobuf/stubs/common.cc:86 #9  0x00007fffde7d490b in mir::protobuf::protobuf_AddDesc_mir_5fprotobuf_2eproto() ()    from /usr/lib/x86_64-linux-gnu/libmirprotobuf.so.3 #10 0x00007fffde7d2409 in ?? () from /usr/lib/x86_64-linux-gnu/libmirprotobuf.so.3 #11 0x00007ffff7de76ba in call_init (l=<optimized out>, argc=argc@entry=1, argv=argv@entry=0x7fffffffd5d8,      env=env@entry=0x7fffffffd5e8) at dl-init.c:72 #12 0x00007ffff7de77cb in call_init (env=0x7fffffffd5e8, argv=0x7fffffffd5d8, argc=1, l=<optimized out>) at dl-init.c:30 #13 _dl_init (main_map=main_map@entry=0xa2f450, argc=1, argv=0x7fffffffd5d8, env=0x7fffffffd5e8) at dl-init.c:120 #14 0x00007ffff7dec8e2 in dl_open_worker (a=a@entry=0x7fffffffc6e0) at dl-open.c:575 #15 0x00007ffff7de7564 in _dl_catch_error (objname=objname@entry=0x7fffffffc6d0, errstring=errstring@entry=0x7fffffffc6d8,      mallocedp=mallocedp@entry=0x7fffffffc6cf, operate=operate@entry=0x7ffff7dec4d0 <dl_open_worker>, args=args@entry=0x7fffffffc6e0)     at dl-error.c:187 #16 0x00007ffff7debda9 in _dl_open (file=0xa2f048 "/opt/Qt5.8.0/5.8/gcc_64/plugins/platformthemes/libqgtk3.so", mode=-2147479551,      caller_dlopen=0x7ffff599b7a8, nsid=-2, argc=<optimized out>, argv=<optimized out>, env=0x7fffffffd5e8) at dl-open.c:660 #17 0x00007ffff1806f09 in dlopen_doit (a=a@entry=0x7fffffffc910) at dlopen.c:66 #18 0x00007ffff7de7564 in _dl_catch_error (objname=0xa02b80, errstring=0xa02b88, mallocedp=0xa02b78,      operate=0x7ffff1806eb0 <dlopen_doit>, args=0x7fffffffc910) at dl-error.c:187 #19 0x00007ffff1807571 in _dlerror_run (operate=operate@entry=0x7ffff1806eb0 <dlopen_doit>, args=args@entry=0x7fffffffc910)     at dlerror.c:163 #20 0x00007ffff1806fa1 in __dlopen (file=<optimized out>, mode=<optimized out>) at dlopen.c:87 #21 0x00007ffff599b7a8 in ?? () from /opt/Qt5.8.0/5.8/gcc_64/lib/libQt5Core.so.5 #22 0x00007ffff5994fd5 in ?? () from /opt/Qt5.8.0/5.8/gcc_64/lib/libQt5Core.so.5 #23 0x00007ffff598a647 in QFactoryLoader::instance(int) const () from /opt/Qt5.8.0/5.8/gcc_64/lib/libQt5Core.so.5 #24 0x00007ffff6b392f1 in ?? () from /opt/Qt5.8.0/5.8/gcc_64/lib/libQt5Gui.so.5 #25 0x00007ffff6b43538 in QGuiApplicationPrivate::createPlatformIntegration() () from /opt/Qt5.8.0/5.8/gcc_64/lib/libQt5Gui.so.5 #26 0x00007ffff6b43edd in QGuiApplicationPrivate::createEventDispatcher() () from /opt/Qt5.8.0/5.8/gcc_64/lib/libQt5Gui.so.5 #27 0x00007ffff59a57d6 in QCoreApplicationPrivate::init() () from /opt/Qt5.8.0/5.8/gcc_64/lib/libQt5Core.so.5 #28 0x00007ffff6b456ab in QGuiApplicationPrivate::init() () from /opt/Qt5.8.0/5.8/gcc_64/lib/libQt5Gui.so.5 #29 0x00007ffff6b46364 in QGuiApplication::QGuiApplication(int&, char**, int) () from /opt/Qt5.8.0/5.8/gcc_64/lib/libQt5Gui.so.5 #30 0x00000000005c55bd in main (argc=1, argv=0x7fffffffd5d8) at /home/mkraus/Documents/dev/star385/src/linux/ui/scan/main.cpp:35 

回答1:

You can find here a discussion about the same issue and they talk about an interesting workaround.

It seems that this error is caused by the library libqgtk3.so located in /opt/Qt/5.9/gcc_64/plugins/platformthemes. If you don't need it in your project you can rename/remove it to make the error go away.

If you are using CMake as a build system you also need to comment all the lines in the file /opt/Qt/5.9/gcc_64/lib/cmake/Qt5Gui/Qt5Gui_QGtk3ThemePlugin.cmake to avoid configure issues.

To add on, the real problem comes from the library libmir which depends on the the libprotobuf. You may run on this problem whenever you try to use recent tensorflow with libgtk3.0 because of this hard dependency. As libmir depends on the system libprotobuf which is normally behind the version in use by tensorflow (which downloads its own version from the repository).

The good news, this BUG on libgtk was reported and fixed however, to use the fixed version you have to move to libgtk3.0 3.22 (see BUG report).

回答2:

If you are using Qt from the Ubuntu package repository, you can remove the offending library by uninstalling qt5-gtk-platformtheme. This will remove libqgtk3.so and the corresponding CMake file without having to resort to hacks that might have unintended consequences.

文章来源: Protobuf version conflicts with Qt