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

jsulm

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

small_bird

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

small_bird

@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.

small_bird

@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.

jsulm

@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?

small_bird

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

SGaist

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

small_bird

@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

small_bird

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

small_bird

@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 !

jsulm

@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.

small_bird

@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.

jsulm

@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.

small_bird

@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 ?

jsulm

@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.

small_bird

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

small_bird

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

small_bird

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

SGaist

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.

small_bird

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