Cross-compiling QT5.7 for linux ARM setting linker path

SimonB

Hello QT community,

This is my first post here, I hope I will get the answers I need !! I have been struggling for a week , trying to compile QT for an ARM device ( based on AM335 ) just like the beaglebone.
I ran across all the qmake.conf files and its includes friends. I am still not ble to find a way to include the proper directory into my build.
The compilation works fine with my toolchain, when it gets to the linker part it can't find : ld-linux.so.3:

"/media/projects/myfolder/toolchain/arm-cortex_a8-linux-gnueabi/bin/../lib/gcc/arm-cortex_a8-linux-gnueabi/4.9.1/../../../../arm-cortex_a8-linux-gnueabi/bin/ld: cannot find /lib/ld-linux.so.3: No such file or directory
collect2: error: ld returned 1 exit status
make: *** [../bin/qmake] Error 1
Error configuring Qt!"

Here is the command used by the linker


arm-cortex_a8-linux-gnueabi-g++ -o "../bin/qmake" project.o option.o property.o main.o ioutils.o proitems.o qmakevfs.o qmakeglobals.o qmakeparser.o qmakeevaluator.o qmakebuiltins.o makefile.o unixmake2.o unixmake.o mingw_make.o winmakefile.o projectgenerator.o meta.o makefiledeps.o metamakefile.o xmloutput.o pbuilder_pbx.o msvc_vcproj.o msvc_vcxproj.o msvc_nmake.o msvc_objectmodel.o msbuild_objectmodel.o cesdkhandler.o qtextcodec.o qutfcodec.o qstring.o qstring_compat.o qstringbuilder.o qtextstream.o qiodevice.o qringbuffer.o qdebug.o qmalloc.o qglobal.o qarraydata.o qbytearray.o qbytearraymatcher.o qdatastream.o qbuffer.o qlist.o qfiledevice.o qfile.o qfilesystementry.o qfilesystemengine.o qfsfileengine.o qfsfileengine_iterator.o qregexp.o qvector.o qbitarray.o qdir.o qdiriterator.o quuid.o qhash.o qfileinfo.o qdatetime.o qstringlist.o qabstractfileengine.o qtemporaryfile.o qmap.o qmetatype.o qsettings.o qsystemerror.o qlibraryinfo.o qvariant.o qvsnprintf.o qlocale.o qlocale_tools.o qlinkedlist.o qnumeric.o qcryptographichash.o qxmlstream.o qxmlutils.o qlogging.o qjson.o qjsondocument.o qjsonparser.o qjsonarray.o qjsonobject.o qjsonvalue.o qfilesystemengine_unix.o qfilesystemiterator_unix.o qfsfileengine_unix.o qlocale_unix.o -Wl,-rpath-link,/media/projects/myfolder/toolchain/arm-cortex_a8-linux-gnueabi/arm-cortex_a8-linux-gnueabi/sysroot/usr/lib/ -Wl,-rpath-link,/media/projects/myfolder/toolchain/arm-cortex_a8-linux-gnueabi/arm-cortex_a8-linux-gnueabi/sysroot/lib/ -Wl,-rpath-link,/media/projects/myfolder/toolchain/arm-cortex_a8-linux-gnueabi/arm-cortex_a8-linux-gnueabi/sysroot/ -Wl,-rpath-link,$[QT_SYSROOT]/usr/lib/ -Wl,-rpath-link,$[QT_SYSROOT]/lib/ -mfloat-abi=hard -mfloat-abi=softfp -Wl,--gc-sections

My qmake.conf :

#
# qmake configuration for the our project
#

include(../common/linux_device_pre.conf)

QT_SYSROOT            =/media/projects/myproject/toolchain/arm-cortex_a8-linux-gnueabi/arm-cortex_a8-linux-gnueabi/sysroot

#Compile and link flags
QMAKE_CFLAGS           = -O3 -march=armv7-a -mtune=cortex-a8 -mfpu=neon -mfloat-abi=softfp
QMAKE_CXXFLAGS         = -O3 -march=armv7-a -mtune=cortex-a8 -mfpu=neon -mfloat-abi=softfp
#QMAKE_LFLAGS           += -v -Wl,-rpath-link,/media/projectsmyproject/toolchain/arm-cortex_a8-linux-gnueabi/arm-cortex_a8-linux-gnueabi/sysroot/lib -Wl,-rpath-link,/media/projects/myproject/toolchain/arm-cortex_a8-linux-gnueabi/arm-cortex_a8-linux-gnueabi/sysroot/usr/lib

QMAKE_LFLAGS           += -Wl,-rpath-link,$${QT_SYSROOT}/usr/lib/$${GCC_MACHINE_DUMP} \
                      -Wl,-rpath-link,$${QT_SYSROOT}/lib/$${GCC_MACHINE_DUMP} \
                      -Wl,-rpath-link,$${QT_SYSROOT}/$${GCC_MACHINE_DUMP}
                      
#Modification to linux_device_pre that came from g++-unix.conf

QMAKE_CC               = arm-cortex_a8-linux-gnueabi-gcc
QMAKE_CXX              = arm-cortex_a8-linux-gnueabi-g++
QMAKE_LINK             = arm-cortex_a8-linux-gnueabi-g++
QMAKE_LINK_SHLIB       = arm-cortex_a8-linux-gnueabi-g++
QMAKE_AR               = arm-cortex_a8-linux-gnueabi-ar cqs
QMAKE_OBJCOPY          = arm-cortex_a8-linux-gnueabi-objcopy
QMAKE_STRIP            = arm-cortex_a8-linux-gnueabi-strip
QMAKE_NM               = arm-cortex_a8-linux-gnueabi-nm -P

QMAKE_INCDIR           = /opt/tslib/include/
QMAKE_LIBDIR           = /opt/tslib/lib/

QMAKE_RPATHDIR        += /opt/tslib/lib

# Extra stuff (OpenGL, DirectFB, ...)
QMAKE_INCDIR_EGL        =
QMAKE_LIBDIR_EGL        =
QMAKE_INCDIR_OPENGL_ES2 = $${QMAKE_INCDIR_EGL}
QMAKE_LIBDIR_OPENGL_ES2 = $${QMAKE_LIBDIR_EGL}
QMAKE_INCDIR_OPENVG     = $${QMAKE_INCDIR_EGL}
QMAKE_LIBDIR_OPENVG     = $${QMAKE_LIBDIR_EGL}

QMAKE_LIBS_EGL          = -lEGL -lIMGegl -lsrv_um
QMAKE_LIBS_OPENGL_ES2   = -lGLESv2 $${QMAKE_LIBS_EGL}
QMAKE_LIBS_OPENVG       = -lOpenVG $${QMAKE_LIBS_EGL}

# No need for any special EGL device integration.
# Prioritize the default, compiled-in integration over any plugins.
EGLFS_DEVICE_INTEGRATION = none

include(../common/linux_arm_device_post.conf)

load(qt_config)

Even after telling it to look in my toolchain folder, ld seems to look into the /lib/ folder anyway.

Any chance someone ran into this problem before ??? ( p.s. ) my folder /lib/ in the toolchain contain the actual file that I need.

SGaist

Hi and welcome to devnet,

What options are you passing to your configure call ?

Note that if your device is like a BBB, you should use the BBB mkspec as a base for yours and pass the proper information to configure.

SimonB

BASE_DIR=$(pwd)
TOOLCHAIN_DIR=$BASE_DIR/../toolchain/arm-cortex_a8-linux-gnueabi
HOST_TYPE=arm-cortex_a8-linux-gnueabi
SYSROOT_DIR=$BASE_DIR/../toolchain/arm-cortex_a8-linux-gnueabi/arm-cortex_a8-linux-gnueabi/sysroot
TARGET_DIR=$BASE_DIR/../buildroot/board/tornatech/filesystem/opt
PREFIX='qt-embedded'
EXTPREFIX=$TARGET_DIR/$PREFIX


CONFIGURE_CMD="./configure -v -xplatform linux-arm-gnueabi-g++ -device linux-brio-tor019-++ -sysroot $SYSROOT_DIR -extprefix $EXTPREFIX -device-option COSS_COMPILE=$TOOLCHAIN_DIR/bin/$HOST_TYPE- -make libs -confirm-license -release -opensource -force-pkg-config -no-icu -no-dbus -no-xcb -no-gif -no-xkbcommon-evdev -no-evdev -tslib -no-mtdev -qt-libjpeg -qt-zlib -no-harfbuzz -no-libproxy -no-xinput2 -no-xcb-xlib -no-pulseaudio -no-alsa -no-largefile -no-iconv -no-pch -no-sse2 -no-glib -no-cups -rpath "

The "device" stated here exist, that's the name of our folder containing the qmake file. My example for the qconf ( in mkspec ) was the beagleboard, the file is almost identical to the beagleboard one, except for the soft floating point

SimonB

Actually, I have to revise my question.
qmake is able to be built, but at the runtime when I try to launch the QT compilation, it ask for

/lib/ld-linux.so.3: No such file or directory

jsulm

@SimonB What does

ldd qmake

say?

SimonB

This post is deleted!

SimonB

@jsulm
It says :

        not a dynamic executable

I guess I am missing a flag or something at compile time, I tried a lot of combinaison for including my "fakeroot" folder. I tought that it was the point of having --sysroot in the configure script

SGaist

What do you get if your call file qmake ?

SimonB

@SGaist - Thanks for your quick reply

qmake: ERROR: cannot open `qmake' (No such file or directory)

I am still looking for a "missing flag" in the conf file ... is there anywhere else I should look ?

I just had a tought,
I want to cross-compile QT to have the libraries on my embedded platform. Am I doing this wrong by building qmake with the cross-compiler app ?
since qmake is used to build the makefile for QT, I have to run it on my host system right ? So, that being said, do I need to have qmake cross-compiled ? sor sure it won't work on my system

my reference was :
Building Qt for Embedded Linux
but it says that this is obsolete and it's only good for QT4, I bet this is good for QT5 as well ??

( This is my first time compiling QT )

SGaist

Ok... When someone suggest to call ldd on a file, you are supposed to give the full path that file or change your current folder to where that file is otherwise the command won't work. The same for file.

As for your qmake.conf i'd remove the QT_SYSROOT assignment, it should be done for you through the configure script and the parameters you give it.

qmake is a host tool that is not cross-compiled.

SimonB

The file and ldd worked, but the binary was a arm compiled binary, that's why it wasn't working. May I suggest updating the http://wiki.qt.io/Building_Qt_for_Embedded_Linux#The_Host_Build to specify that it's still the actual way to to it, even in qt5

@SGaist said in Cross-compiling QT5.7 for linux ARM setting linker path:

qmake is a host tool that is not cross-compiled.

I figured that out today !! I am still wondering why it is trying to compile qmake with the cross compiler when I make the second configure ( the one with the option -device CROSSC_COMPILE= ....

SGaist

Are you doing your second call to configure in a clean state ?

SGaist

The article you mention is really specific to Qt 4. So no, it should not be modified. There's even a link at the top for Qt 5.