When I configure Qt 5.6, it shows that xcb failed! Why?



  • When I configured Qt 5.6 source code using Ubuntu 12.04 lts, I came across this problem:
    "xcb auto-detection... ()
    arm-linux-g++ -lts -c -pipe -O2 -Wall -W -fPIC -I. -I../../../mkspecs/linux-arm-gnueabi-g++ -o xcb.o xcb.cpp
    xcb.cpp:34: fatal error: xcb/xcb.h: No such file or directory
    compilation terminated.
    make: *** [xcb.o] Error 1
    xcb disabled.
    The test for linking against libxcb failed!
    You might need to install dependency packages for libxcb.
    See src/plugins/platforms/xcb/README.
    "
    However, the packages are all installed. Could anyone help me? Thanks in advance!


  • Lifetime Qt Champion

    Hi,

    Are they installed for your target ?



  • @SGaist Yes, I cross compile qt5.6 source code for my arm board.


  • Moderators

    @small_bird Are you really sure xcb is installed for your target (not for Ubuntu host machine)?
    This error tells you that xcb header file could not be found, so at least the xcb-dev package is not installed:

    xcb.cpp:34: fatal error: xcb/xcb.h: No such file or directory
    


  • @jsulm Yes the xcb is installed for my target.
    root@ubuntu:/opt/qt-everywhere-opensource-src-5.6.0# dpkg -l|grep xcb
    ii libx11-xcb-dev 2:1.6.3-1ubuntu2 Xlib/XCB interface library (development headers)
    ii libx11-xcb1 2:1.6.3-1ubuntu2 Xlib/XCB interface library
    ii libx11-xcb1-dbg 2:1.6.3-1ubuntu2 Xlib/XCB interface library (debug package)
    ii libxcb-composite0 1.11.1-1ubuntu1 X C Binding, composite extension
    ii libxcb-composite0-dbg 1.11.1-1ubuntu1 X C Binding, composite extension, debugging symbols
    ii libxcb-composite0-dev 1.11.1-1ubuntu1 X C Binding, composite extension, development files
    ii libxcb-cursor-dev 0.1.1-3ubuntu1 utility libraries for X C Binding -- cursor, development files
    ii libxcb-cursor0 0.1.1-3ubuntu1 utility libraries for X C Binding -- cursor
    ii libxcb-damage0 1.11.1-1ubuntu1 X C Binding, damage extension
    ii libxcb-damage0-dbg 1.11.1-1ubuntu1 X C Binding, damage extension, debugging symbols
    ii libxcb-damage0-dev 1.11.1-1ubuntu1 X C Binding, damage extension, development files
    ii libxcb-doc 1.11.1-1ubuntu1 X C Binding, development documentation
    ii libxcb-dpms0 1.11.1-1ubuntu1 X C Binding, dpms extension
    ii libxcb-dpms0-dbg 1.11.1-1ubuntu1 X C Binding, dpms extension, debugging symbols
    ii libxcb-dpms0-dev 1.11.1-1ubuntu1 X C Binding, dpms extension, development files
    ii libxcb-dri2-0 1.11.1-1ubuntu1 X C Binding, dri2 extension
    ii libxcb-dri2-0-dbg 1.11.1-1ubuntu1 X C Binding, dri2 extension, debugging symbols
    ii libxcb-dri2-0-dev 1.11.1-1ubuntu1 X C Binding, dri2 extension, development files
    ii libxcb-dri3-0 1.11.1-1ubuntu1 X C Binding, dri3 extension
    ii libxcb-dri3-0-dbg 1.11.1-1ubuntu1 X C Binding, dri3 extension, debugging symbols
    ii libxcb-dri3-dev 1.11.1-1ubuntu1 X C Binding, dri3 extension, development files
    ii libxcb-ewmh-dev 0.4.1-1ubuntu1 utility libraries for X C Binding -- ewmh, development files
    ii libxcb-ewmh1 0.3.8-1build1 utility libraries for X C Binding -- ewmh
    ii libxcb-ewmh2 0.4.1-1ubuntu1 utility libraries for X C Binding -- ewmh
    ii libxcb-glx0 1.11.1-1ubuntu1 X C Binding, glx extension
    ii libxcb-glx0-dbg 1.11.1-1ubuntu1 X C Binding, glx extension, debugging symbols
    ii libxcb-glx0-dev 1.11.1-1ubuntu1 X C Binding, glx extension, development files
    ii libxcb-icccm4 0.4.1-1ubuntu1 utility libraries for X C Binding -- icccm
    ii libxcb-icccm4-dev 0.4.1-1ubuntu1 utility libraries for X C Binding -- icccm, development files
    ii libxcb-image0 0.4.0-1build1 utility libraries for X C Binding -- image
    ii libxcb-image0-dev 0.4.0-1build1 utility libraries for X C Binding -- image, development files
    ii libxcb-keysyms1 0.4.0-1 utility libraries for X C Binding -- keysyms
    ii libxcb-keysyms1-dev 0.4.0-1 utility libraries for X C Binding -- keysyms, development files
    ii libxcb-present-dev 1.11.1-1ubuntu1 X C Binding, present extension, development files
    ii libxcb-present0 1.11.1-1ubuntu1 X C Binding, present extension
    ii libxcb-present0-dbg 1.11.1-1ubuntu1 X C Binding, present extension, debugging symbols
    ii libxcb-randr0 1.11.1-1ubuntu1 X C Binding, randr extension
    ii libxcb-randr0-dbg 1.11.1-1ubuntu1 X C Binding, randr extension, debugging symbols
    ii libxcb-randr0-dev 1.11.1-1ubuntu1 X C Binding, randr extension, development files
    ii libxcb-record0 1.11.1-1ubuntu1 X C Binding, record extension
    ii libxcb-record0-dbg 1.11.1-1ubuntu1 X C Binding, record extension, debugging symbols
    ii libxcb-record0-dev 1.11.1-1ubuntu1 X C Binding, record extension, development files
    ii libxcb-render-util0 0.3.9-1 utility libraries for X C Binding -- render-util
    ii libxcb-render-util0-dev 0.3.9-1 utility libraries for X C Binding -- render-util
    ii libxcb-render0 1.11.1-1ubuntu1 X C Binding, render extension
    ii libxcb-render0-dbg 1.11.1-1ubuntu1 X C Binding, render extension, debugging symbols
    ii libxcb-render0-dev 1.11.1-1ubuntu1 X C Binding, render extension, development files
    ii libxcb-res0 1.11.1-1ubuntu1 X C Binding, res extension
    ii libxcb-res0-dbg 1.11.1-1ubuntu1 X C Binding, res extension, debugging symbols
    ii libxcb-res0-dev 1.11.1-1ubuntu1 X C Binding, res extension, development files
    ii libxcb-screensaver0 1.11.1-1ubuntu1 X C Binding, screensaver extension
    ii libxcb-screensaver0-dbg 1.11.1-1ubuntu1 X C Binding, screensaver extension, debugging symbols
    ii libxcb-screensaver0-dev 1.11.1-1ubuntu1 X C Binding, screensaver extension, development files
    ii libxcb-shape0 1.11.1-1ubuntu1 X C Binding, shape extension
    ii libxcb-shape0-dbg 1.11.1-1ubuntu1 X C Binding, shape extension, debugging symbols
    ii libxcb-shape0-dev 1.11.1-1ubuntu1 X C Binding, shape extension, development files
    ii libxcb-shm0 1.11.1-1ubuntu1 X C Binding, shm extension
    ii libxcb-shm0-dbg 1.11.1-1ubuntu1 X C Binding, shm extension, debugging symbols
    ii libxcb-shm0-dev 1.11.1-1ubuntu1 X C Binding, shm extension, development files
    ii libxcb-sync-dev 1.11.1-1ubuntu1 X C Binding, sync extension, development files
    ii libxcb-sync0 1.8.1-1ubuntu0.2 X C Binding, sync extension
    ii libxcb-sync0-dbg 1.8.1-1ubuntu0.2 X C Binding, sync extension, debugging symbols
    ii libxcb-sync1 1.11.1-1ubuntu1 X C Binding, sync extension
    ii libxcb-sync1-dbg 1.11.1-1ubuntu1 X C Binding, sync extension, debugging symbols
    ii libxcb-util-dev 0.4.0-0ubuntu3 utility libraries for X C Binding -- atom, aux and event
    ii libxcb-util0 0.3.8-2 utility libraries for X C Binding -- atom, aux and event
    ii libxcb-util0-dev 0.4.0-0ubuntu3 dummy transitional package for utility libraries for X C Binding -- atom, aux and event
    ii libxcb-util1 0.4.0-0ubuntu3 utility libraries for X C Binding -- atom, aux and event
    ii libxcb-xevie0 1.11.1-1ubuntu1 X C Binding, xevie extension
    ii libxcb-xevie0-dbg 1.11.1-1ubuntu1 X C Binding, xevie extension, debugging symbols
    ii libxcb-xevie0-dev 1.11.1-1ubuntu1 X C Binding, xevie extension, development files
    ii libxcb-xf86dri0 1.11.1-1ubuntu1 X C Binding, xf86dri extension
    ii libxcb-xf86dri0-dbg 1.11.1-1ubuntu1 X C Binding, xf86dri extension, debugging symbols
    ii libxcb-xf86dri0-dev 1.11.1-1ubuntu1 X C Binding, xf86dri extension, development files
    ii libxcb-xfixes0 1.11.1-1ubuntu1 X C Binding, xfixes extension
    ii libxcb-xfixes0-dbg 1.11.1-1ubuntu1 X C Binding, xfixes extension, debugging symbols
    ii libxcb-xfixes0-dev 1.11.1-1ubuntu1 X C Binding, xfixes extension, development files
    ii libxcb-xinerama0 1.11.1-1ubuntu1 X C Binding, xinerama extension
    ii libxcb-xinerama0-dbg 1.11.1-1ubuntu1 X C Binding, xinerama extension, debugging symbols
    ii libxcb-xinerama0-dev 1.11.1-1ubuntu1 X C Binding, xinerama extension, development files
    ii libxcb-xkb-dev 1.11.1-1ubuntu1 X C Binding, XKEYBOARD extension, development files
    ii libxcb-xkb1 1.11.1-1ubuntu1 X C Binding, XKEYBOARD extension
    ii libxcb-xkb1-dbg 1.11.1-1ubuntu1 X C Binding, XKEYBOARD extension, debugging symbols
    ii libxcb-xprint0 1.11.1-1ubuntu1 X C Binding, xprint extension
    ii libxcb-xprint0-dbg 1.11.1-1ubuntu1 X C Binding, xprint extension, debugging symbols
    ii libxcb-xprint0-dev 1.11.1-1ubuntu1 X C Binding, xprint extension, development files
    ii libxcb-xtest0 1.11.1-1ubuntu1 X C Binding, xtest extension
    ii libxcb-xtest0-dbg 1.11.1-1ubuntu1 X C Binding, xtest extension, debugging symbols
    ii libxcb-xtest0-dev 1.11.1-1ubuntu1 X C Binding, xtest extension, development files
    ii libxcb-xv0 1.11.1-1ubuntu1 X C Binding, xv extension
    ii libxcb-xv0-dbg 1.11.1-1ubuntu1 X C Binding, xv extension, debugging symbols
    ii libxcb-xv0-dev 1.11.1-1ubuntu1 X C Binding, xv extension, development files
    ii libxcb-xvmc0 1.11.1-1ubuntu1 X C Binding, xvmc extension
    ii libxcb-xvmc0-dbg 1.11.1-1ubuntu1 X C Binding, xvmc extension, debugging symbols
    ii libxcb-xvmc0-dev 1.11.1-1ubuntu1 X C Binding, xvmc extension, development files
    ii libxcb1 1.11.1-1ubuntu1 X C Binding
    ii libxcb1-dbg 1.11.1-1ubuntu1 X C Binding, debugging symbols
    ii libxcb1-dev 1.11.1-1ubuntu1 X C Binding, development files
    ii xcb 2.4-4.1 Pigeon holes for your cut and paste selections
    You see that? I have installed all packages.


  • Moderators

    @small_bird As I already said you need to install it on your target device/sysroot not your Ubuntu machine!
    You're cross-compiling, right? That means you need libs/headers for your target platform.


  • Moderators

    @small_bird "root@ubuntu:/opt/qt-everywhere-opensource-src-5.6.0# dpkg -l|grep xcb" - so you're on your Ubuntu host machine, right? Why are you logged on as root? You never should work as root! Put Qt source-code somewhere in your home directory instead of /opt then you don't need root to build. /opt is quite unusual location for source code.



  • @jsulm Hi, now I change my home directory to /home/smallbird("smallbird" is my user name), but I get the following result:
    xcb auto-detection... ()
    g++ -c -pipe -O2 -Wall -W -fPIC -I. -I/home/smallbird/tslib1.4/include -I/home/smallbird/GLES2 -I../../../mkspecs/linux-arm-gnueabi-g++ -o xcb.o xcb.cpp
    xcb.cpp: In function ‘int main(int, char**)’:
    xcb.cpp:39:23: warning: unused variable ‘t’ [-Wunused-variable]
    xcb_connection_t *t = xcb_connect("", &primaryScreen);
    ^
    arm-linux-g++ -Wl,-O1 -o xcb xcb.o -L/home/smallbird/openglES2libs-x86 -lGLESv2 -lts -lrt -lpthread -L/home/smallbird/tslib1.4/lib -lxcb
    /home/smallbird/arm-2009q3/bin/../lib/gcc/arm-none-linux-gnueabi/4.4.1/../../../../arm-none-linux-gnueabi/bin/ld: xcb.o: Relocations in generic ELF (EM: 3)
    /home/smallbird/arm-2009q3/bin/../lib/gcc/arm-none-linux-gnueabi/4.4.1/../../../../arm-none-linux-gnueabi/bin/ld: xcb.o: Relocations in generic ELF (EM: 3)
    xcb.o: could not read symbols: File in wrong format
    collect2: ld returned 1 exit status
    Makefile:84: recipe for target 'xcb' failed
    make: *** [xcb] Error 1
    xcb disabled.
    The test for linking against libxcb failed!
    You might need to install dependency packages for libxcb.
    See src/plugins/platforms/xcb/README.

    Could you help me? Thanks in advance!


  • Moderators

    @small_bird Now you're using your host PC g++ compiler instead of the cross-compiler (arm-linux-g++). You used the correct compiler before, why do you use the wrong compiler now?
    Now:

    xcb auto-detection... ()
    g++ -c -pipe -O2 -Wall -W -fPIC -I. -I/home/smallbird/tslib1.4/include -I/home/smallbird/GLES2 -I../../../mkspecs/linux-arm-gnueabi-g++ -o xcb.o xcb.cpp
    

    before

    xcb auto-detection... ()
    arm-linux-g++ -lts -c -pipe -O2 -Wall -W -fPIC -I. -I../../../mkspecs/linux-arm-gnueabi-g++ -o xcb.o xcb.cpp
    


  • @jsulm No ,It is arm-linux-g++.

    As this line shows:
    arm-linux-g++ -Wl,-O1 -o xcb xcb.o -L/home/smallbird/openglES2libs-x86 -lGLESv2 -lts -lrt -lpthread -L/home/smallbird/tslib1.4/lib -lxcb

    Am I right?


  • Moderators

    @small_bird You're using wrong compiler to compile but the cross-compiler to link. I updated my previous post.



  • @jsulm OK, I have saw that. I'd check my parameter.



  • @jsulm It is quite strange, I have the qmake.conf like this:

    modifications to g++.conf

    QMAKE_CC = arm-linux-gcc -lts
    QMAKE_LINK = arm-linux-g++ -lts
    QMAKE_LINK_SHLIB = arm-linux-g++ -lts

    modifications to linux.conf

    QMAKE_AR = arm-linux-ar cqs
    QMAKE_OBJCOPY = arm-linux-objcopy
    QMAKE_NM = arm-linux-nm -P
    QMAKE_STRIP = arm-linux-strip

    You see that? I have already set the paremeter.



  • @jsulm Ok, now I have solved the problem. I added one line to the qmake.conf file, now the file is like this:

    Now:

    modifications to g++.conf

    QMAKE_CC = arm-linux-gcc -lts
    QMAKE_CXX = arm-linux-g++ -lts
    QMAKE_LINK = arm-linux-g++ -lts
    QMAKE_LINK_SHLIB = arm-linux-g++ -lts

    modifications to linux.conf

    QMAKE_AR = arm-linux-ar cqs
    QMAKE_OBJCOPY = arm-linux-objcopy
    QMAKE_NM = arm-linux-nm -P
    QMAKE_STRIP = arm-linux-strip

    Before:

    modifications to g++.conf

    QMAKE_CC = arm-linux-gcc -lts
    QMAKE_LINK = arm-linux-g++ -lts
    QMAKE_LINK_SHLIB = arm-linux-g++ -lts

    modifications to linux.conf

    QMAKE_AR = arm-linux-ar cqs
    QMAKE_OBJCOPY = arm-linux-objcopy
    QMAKE_NM = arm-linux-nm -P
    QMAKE_STRIP = arm-linux-strip
    load(qt_config)

    However, I got the following result:

    xcb auto-detection... ()
    arm-linux-g++ -lts -c -pipe -O2 -Wall -W -fPIC -I. -I/home/smallbird/tslib1.4/include -I../../../mkspecs/linux-arm-gnueabi-g++ -o xcb.o xcb.cpp
    xcb.cpp:34: fatal error: xcb/xcb.h: No such file or directory
    compilation terminated.
    Makefile:172: recipe for target 'xcb.o' failed
    make: *** [xcb.o] Error 1
    xcb disabled.
    The test for linking against libxcb failed!
    You might need to install dependency packages for libxcb.
    See src/plugins/platforms/xcb/README.

    Why?The packages are all installed.


  • Moderators

    @small_bird said in When I configure qt5.6, it shows that xcb failed! Why?:

    xcb/xcb.h

    Is xcb/xcb.h there? And if so where exactly is it?



  • @jsulm Yes, it is there.
    It is located in /home/smallbird/qt-everywhere-opensource-src-5.6.0/qtbase/src/3rdparty/xcb/sysinclude.


  • Lifetime Qt Champion

    If you are using Qt's 3rdparty xcb, you should say so in the configure options.



  • @SGaist Yes, I have added -qt-xcb option, my configure is as following:
    #!/bin/sh
    ./configure
    -v
    -prefix /home/smallbird/qt5.6.0
    -release
    -continue
    -confirm-license
    -plugin-sql-sqlite
    -qt-libjpeg
    -qt-libpng
    -qt-zlib
    -no-c++11
    -qt-xcb
    -opensource
    -xplatform linux-arm-gnueabi-g++
    -force-pkg-config
    -make examples
    -no-dbus
    -pkg-config
    -qt-freetype
    -qt-pcre
    -I/home/smallbird/tslib1.4/include
    -L/home/smallbird/tslib1.4/lib

    exit



  • @jsulm
    As I did not designate the sysroot option, the compiler should seek the headers and libraries in the folder /usr/include.
    Now the folder has the xcb/xcb.h. However the result is still the same:

    "xcb auto-detection... ()
    arm-linux-g++ -lts -c -pipe -O2 -Wall -W -fPIC -I. -I../../../mkspecs/linux-arm-gnueabi-g++ -o xcb.o xcb.cpp
    xcb.cpp:34: fatal error: xcb/xcb.h: No such file or directory
    compilation terminated.
    Makefile:172: recipe for target 'xcb.o' failed
    make: *** [xcb.o] Error 1
    xcb disabled.
    The test for linking against libxcb failed!
    You might need to install dependency packages for libxcb.
    See src/plugins/platforms/xcb/README.
    "
    How could it be like that? This is my /usr/include:
    root@ubuntu:/home/smallbird/qt-everywhere-opensource-src-5.6.0# ls /usr/include/
    aio.h expat_external.h lastlog.h netipx rpcsvc termios.h
    aliases.h expat.h libgen.h netiucv sched.h tgmath.h
    alloca.h fcntl.h libintl.h netpacket scsi thread_db.h
    argp.h features.h libio.h netrom search.h time.h
    argz.h fenv.h libpng netrose semaphore.h ttyent.h
    ar.h fmtmsg.h libpng12 nfs setjmp.h uapi
    arpa fnmatch.h limits.h nl_types.h sgtty.h uchar.h
    asm-generic fontconfig link.h nss.h shadow.h ucontext.h
    assert.h freetype2 linux obstack.h signal.h ulimit.h
    autosprintf.h fstab.h locale.h paths.h sound unistd.h
    byteswap.h fts.h malloc.h pngconf.h spawn.h ustat.h
    c++ ftw.h math.h png.h stab.h utime.h
    complex.h _G_config.h mcheck.h poll.h stdc-predef.h utmp.h
    cpio.h gconv.h memory.h printf.h stdint.h utmpx.h
    crypt.h getopt.h misc protocols stdio_ext.h values.h
    ctype.h gettext-po.h mntent.h pthread.h stdio.h video
    dirent.h glob.h monetary.h pty.h stdlib.h wait.h
    dlfcn.h gnumake.h mqueue.h pwd.h string.h wchar.h
    drm gnu-versions.h mtd python3.5m strings.h wctype.h
    elf.h grp.h net rdma stropts.h wordexp.h
    endian.h gshadow.h netash re_comp.h sudo_plugin.h X11
    envz.h i386-linux-gnu netatalk regex.h syscall.h xcb
    err.h iconv.h netax25 regexp.h sysexits.h xen
    errno.h ifaddrs.h netdb.h reglib syslog.h xlocale.h
    error.h inttypes.h neteconet resolv.h tar.h xorg
    execinfo.h langinfo.h netinet rpc termio.h zlib.h

    This is what xcb folder contains:

    root@ubuntu:/home/smallbird/qt-everywhere-opensource-src-5.6.0# ls /usr/include/xcb/
    bigreq.h glx.h screensaver.h xcb_cursor.h xcb_image.h xevie.h xproto.h
    composite.h present.h shape.h xcb_event.h xcb_keysyms.h xf86dri.h xtest.h
    damage.h randr.h shm.h xcb_ewmh.h xcb_pixel.h xfixes.h xv.h
    dpms.h record.h sync.h xcbext.h xcb_renderutil.h xinerama.h xvmc.h
    dri2.h render.h xcb_atom.h xcb.h xcb_util.h xkb.h
    dri3.h res.h xcb_aux.h xcb_icccm.h xc_misc.h xprint.h

    You might say that I should not use the super user as root, but if not, some folders could not be entered. Could you offer me help? Thanks a lot!



  • @SGaist Someone told me : "You don't have X11 development packages installed for the arm target, then. Stuff in /usr/include/X11 is for the host, not for the target." However, I wonder how to install the packages for the arm target !


  • Moderators

    @small_bird In another thread I told you that you need a sysroot to cross compile. The content of /usr on your host PC is completely unrelated to your target device. What is your device? What Linux distribution is running on it (I assume you're using Linux)? You really should read about cross-compiling.



  • @jsulm My device is arm-cortexA8. The linux distribution is based on linux3.2, not a offical distribution. I know what you mean, then where can I get the headers and libraries for the device.


  • Moderators

    @small_bird So, on your device Ubuntu is running, right?
    In that case start it log on on it (remotely over SSH or directly if you can connect a monitor and keyboard) and use apt-get to install all needed packages.



  • @jsulm I am sorry that I have corrected the answer. According to the offical description, the distribution installed on PC is the same as that on the arm board. So after I use cross-compiler to compile the qt5.6 source code, the libraries it generates should be avaliable for the arm board. Why should I install the packages on the board ?


  • Moderators

    @small_bird Could you please read about cross-compiling?
    I already provided a link in one of your threads.
    What you need is a sysroot containing libraries AND include files for your target architecture.
    Lets say you cross-compile your app which depends on a library. In your code you include header files needed to use that library. Now the question is where are the library and its header files? You cannot use what is installed on your host PC as it is for a different architecture (your PC is most probably x86_64, right?). So, you need a sysroot containing that lib and header files. One way to get that sysroot is to mount the file system from your target device in your PC. If you're using Raspberry Pi (you still didn't say what your device actually is, arm-cortexA8 is not a device it is a CPU architecture) you can just put the SD card into your PC and mount it - then you have a sysroot.



  • @jsulm Thanks a lot for your patient reply ! My device is OK335XD, you might not hear that.



  • @jsulm Now I will follow your advice and have a try. Thanks once more !



  • @jsulm The linux installed on my board does not have apt-get command. It is the edition reduced.


  • Lifetime Qt Champion

    Can you tell what exactly is running on that board ? It could be a yocto based image or something similar which could potentially simplify the situation.

    Also, it seems that we are currently answering in parallel on this thread for exactly the same problem. So I propose to stop the other one and continue here.



  • @SGaist It is the linux edition designed by the FORLINX company based on linux3.2 core, not the distribution like ubuntu, etc.



  • Ok! I've solved the problem. My cross-compiler edition is wrong. Thank all the people above !


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