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Qt for embedded platforms on LPC3250 - Thumb mode error on make

  • Hi to all,

    in previous posts regarding this problem the question was widely discussed. To see the history you can check to the following links:

    "Installing Qt framework on embedded Linux":
    "Qt on embedded platforms and “QT for embedded linux”":

    Following the precious advices of ZapB I setup correctly the working environment with the gnu-gcc toolchain working fine. To be sure, due to some minor changes like the compiler folder and come compiler names that does not match exactly with the original .../mkspecs/qws/linux-arm-gnueabi-g++ was recreated defining a customized copy with the name ubuntu-linux-arm-gnueabi-g++

    The hardware platform is an arm cpu that has already the linux on board working without problems. The toolchain used for the linux kernel and file system build was configured by myself using the Ltib toolchain and the cpu is LPC3250 from NXP. The hardware manufacturers told me that it works in little-endian mode.

    At this point I have launched the ./configure as follows:

    @./configure -prefix /home/enrico/qt-ea3250 -prefix-install -embedded armv7 -xplatform qws/linux-ubuntu-arm-gnueabi-g++ -qt-gfx-linuxfb -qt-gfx-vnc -no-largefile -no-accessibility -no-qt3support -no-sse2 -qt-libpng -qt-libjpeg -no-cups -no-libtiff -qt-zlib@

    The compilation goes ahead without any error and all seems working fine. Then, I launch make
    Make starts linking all the objects and after some minute I obtain the following dramatic message:

    @{standard input}: Assembler messages:
    {standard input}:2467: Error: selected processor does not support Thumb mode swp r6,r4,[r3]' make[1]: *** [.obj/release-shared-emb-arm/qobject.o] Error 1 make[1]: Leaving directory/home/enrico/qt-everywhere-opensource-src-4.7.3/src/corelib'@

    The strangeness is that the Thumb mode is a normal feature of Arm processors not a special characteristic of this CPU.

    At this point the make process stop and I have not any idea of what should be done.
    It seems that this error is a known unsolved bug of Qt for embedded but I have not found any workaround to manage it. Should I surrender and find another way?

    Any help is appreciated.

  • Hi Alicemirror,

    May be the problem is related to the target.

    See the configure that you use:

    ./configure -prefix /home/enrico/qt-ea3250 -prefix-install -embedded armv7 -xplatform qws/linux-ubuntu-arm-gnueabi-g++ -qt-gfx-linuxfb -qt-gfx-vnc -no-largefile -no-accessibility -no-qt3support -no-sse2 -qt-libpng -qt-libjpeg -no-cups -no-libtiff -qt-zlib

    ARMv7 is the cortex A series. ARMv5 is the ARM9E, ARM11E and XScale series , and LPC3250 is an ARM926-EJ (I get this information on ELDK 5.0 page "here": Try to change to -embedded armv5 or -embedded armv5te and post the results.


  • Many thanks to you!!! It's so much time that I have lost any hopes that someone can help me. As a matter of fact there is also another thread I have opened where Zapb suggested to try with the Qt 4.8 that will solve the problem related to this particular target. It seems a known bug. But I'll try anyway asap your advice.

    Thanks again! Enrico

  • Hi Enrico,

    I'm also trying to use LTIB + Qt to make applications to EA LPC3250 board, then looking for more information on how to start I saw your post. I hope this tip could help you.


  • Sure, it can help very much.

    What platform are you using ? If you want we chan chat about the question for a more complete scenario and exchange of experiences.

  • hi....there....

    I am also this kind of messege....while using sudo make....

    selected processor does not support Thumb mode `swp r4,r3,[r2]'

    I am using it for armv4t.....for my mini2440 tool chain is : arm-linux-gnueabi-

    Any help will be appreciated....!

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