Cross Compilation Qt6.3.1 for Raspberry Pi 4

UnderCSkele

Hi, I'm trying to cross compile Qt6.3.1 for Raspberry Pi 4. I am following this guide https://wiki.qt.io/Cross-Compile_Qt_6_for_Raspberry_Pi.

I have got this working previously with a Raspberry Pi OS Bullseye install but now it is not working and I haven't changed anything particularly.

I have gotten several different issues that I've pushed past through. I will list some of them for context and if anyone has answers towards:

Toolchain.cmake does not work with Linaro aarch64 compilers, but it works with the gcc arm compilers installed through apt repository.
I tried to compile with target ARM Ubuntu 20.04 Server version as well but that was also unsuccessful.
When it was working previously, I could only use LinuxFB. For some reason EGLFS was not working.
This is my current blocking issue. Using TARGET: Raspberry Pi Bullseye Sysroot and HOST: Ubuntu 20.04 x86.
After successfully configuring, but then it fails during building.

sudo ../../qt6source/configure -release -opengl es2 -nomake examples -nomake tests -qt-host-path $HOME/hostQt/install -prefix /usr/local/qt6 -extprefix $HOME/rpi/install -device-option CROSS_COMPILE=aarch64-linux-gnu- -- -DCMAKE_TOOLCHAIN_FILE=$HOME/rpi/tools/toolchain.cmake -DQT_FEATURE_xcb=ON -DFEATURE_xcb_xlib=ON -DQT_FEATURE_xlib=ON -DTEST_egl_brcm=ON
+ mkdir -p qtbase
+ cd qtbase
+ exec /home/shady/qt6source/qtbase/configure -top-level -release -opengl es2 -nomake examples -nomake tests -qt-host-path /home/shady/hostQt/install -prefix /usr/local/qt6 -extprefix /home/shady/rpi/install -device-option CROSS_COMPILE=aarch64-linux-gnu- -- -DCMAKE_TOOLCHAIN_FILE=/home/shady/rpi/tools/toolchain.cmake -DQT_FEATURE_xcb=ON -DFEATURE_xcb_xlib=ON -DQT_FEATURE_xlib=ON -DTEST_egl_brcm=ON
'/usr/bin/cmake' '-DQT_HOST_PATH=/home/shady/hostQt/install' '-DCMAKE_TOOLCHAIN_FILE=/home/shady/rpi/tools/toolchain.cmake' '-DQT_FEATURE_xcb=ON' '-DFEATURE_xcb_xlib=ON' '-DQT_FEATURE_xlib=ON' '-DTEST_egl_brcm=ON' '-DCMAKE_INSTALL_PREFIX=/usr/local/qt6' '-DCMAKE_STAGING_PREFIX=/home/shady/rpi/install' '-DQT_BUILD_EXAMPLES=FALSE' '-DQT_BUILD_TESTS=FALSE' '-DCMAKE_BUILD_TYPE=Release' '-DQT_QMAKE_DEVICE_OPTIONS=CROSS_COMPILE=aarch64-linux-gnu-' '-DINPUT_opengl=es2' '-G' 'Ninja' '/home/shady/qt6source'
-- The CXX compiler identification is GNU 9.4.0
-- The C compiler identification is GNU 9.4.0
-- The ASM compiler identification is GNU
-- Found assembler: /usr/bin/aarch64-linux-gnu-gcc-9
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /usr/bin/aarch64-linux-gnu-g++-9 - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: /usr/bin/aarch64-linux-gnu-gcc-9 - skipped
-- Detecting C compile features
-- Detecting C compile features - done
Checking dependencies of submodule 'qtbase'
Checking dependencies of submodule 'qtimageformats'
Checking dependencies of submodule 'qtlanguageserver'
Checking dependencies of submodule 'qtshadertools'
Checking dependencies of submodule 'qtsvg'
Checking dependencies of submodule 'qtdeclarative'
Skipping optional dependency 'qtimageformats' of 'qtdeclarative', because qtimageformats's CMakeLists.txt couldn't be found.
Skipping optional dependency 'qtlanguageserver' of 'qtdeclarative', because qtlanguageserver's CMakeLists.txt couldn't be found.
Skipping optional dependency 'qtsvg' of 'qtdeclarative', because qtsvg's CMakeLists.txt couldn't be found.
Checking dependencies of submodule 'qt5compat'
Configuring submodule 'qtbase'
-- Could NOT find double-conversion (missing: double-conversion_DIR)
-- Could NOT find md4c (missing: md4c_DIR)
CMake Warning (dev) at qtbase/cmake/3rdparty/extra-cmake-modules/find-modules/FindXCB.cmake:180 (message):
  XINPUT from XCB was requested: this is EXPERIMENTAL and is likely to
  unavailable on many systems!
Call Stack (most recent call first):
  qtbase/cmake/QtFindPackageHelpers.cmake:130 (find_package)
  qtbase/src/gui/configure.cmake:123 (qt_find_package)
  qtbase/cmake/QtFeature.cmake:573 (include)
  qtbase/src/CMakeLists.txt:12 (qt_feature_evaluate_features)
This warning is for project developers.  Use -Wno-dev to suppress it.

-- Could NOT find double-conversion (missing: double-conversion_DIR)
-- Could NOT find md4c (missing: md4c_DIR)
CMake Warning (dev) at qtbase/cmake/3rdparty/extra-cmake-modules/find-modules/FindXCB.cmake:180 (message):
  XINPUT from XCB was requested: this is EXPERIMENTAL and is likely to
  unavailable on many systems!
Call Stack (most recent call first):
  qtbase/cmake/QtFindPackageHelpers.cmake:130 (find_package)
  qtbase/src/gui/configure.cmake:123 (qt_find_package)
  qtbase/cmake/QtModuleHelpers.cmake:572 (include)
  qtbase/src/gui/CMakeLists.txt:53 (qt_internal_add_module)
This warning is for project developers.  Use -Wno-dev to suppress it.

Configuring submodule 'qtimageformats'
Configuring submodule 'qtlanguageserver'
Configuring submodule 'qtshadertools'
-- Check if compiler accepts -pthread
-- Check if compiler accepts -pthread - yes
Configuring submodule 'qtsvg'
Configuring submodule 'qtdeclarative'
Configuring submodule 'qt5compat'
-- The following packages have been found:

 * QtBuildInternals
 * WrapSystemZLIB (required version >= 1.0.8)
 * DBus1 (required version >= 1.2)
 * WrapDBus1 (required version >= 1.2)
 * Libudev
 * Backtrace
 * OpenSSL
 * JPEG
 * ZLIB
 * PNG
 * OpenGL
 * WrapPCRE2
 * WrapZLIB
 * WrapBacktrace
 * ICU
 * WrapRt
 * WrapSystemPCRE2 (required version >= 10.20)
 * WrapBrotli
 * WrapOpenSSLHeaders
 * WrapOpenSSL
 * GLIB2, Event loop and utility library, <https://wiki.gnome.org/Projects/GLib>
 * WrapHarfbuzz
 * WrapPNG
 * ATSPI2
 * DirectFB
 * WrapSystemFreetype (required version >= 2.2.0)
 * gbm, Mesa gbm library., <http://www.mesa3d.org>
 * WrapSystemJpeg
 * WrapSystemPNG
 * WrapOpenGL
 * Wayland, C library implementation of the Wayland protocol: a protocol for a compositor to talk to its clients, <http://wayland.freedesktop.org>
 * Freetype
 * Fontconfig
 * X11
 * X11_XCB, A compatibility library for code that translates Xlib API calls into XCB calls, <http://xorg.freedesktop.org/>
 * XCB (required version >= 1.12), X protocol C-language Binding, <http://xcb.freedesktop.org>
 * XKB_COMMON_X11 (required version >= 0.5.0)
 * XRender (required version >= 0.6)
 * Libinput, Library to handle input devices in Wayland compositors and to provide a generic X.Org input driver., <http://www.freedesktop.org/wiki/Software/libinput/>
 * Mtdev
 * Libdrm, Userspace interface to kernel DRM services., <https://wiki.freedesktop.org/dri/>
 * SQLite3
 * Interbase, Interbase client library, <https://www.embarcadero.com/products/interbase>
 * PostgreSQL
 * WrapFreetype
 * WrapJpeg
 * Tslib
 * Cups
 * Qt6WidgetsTools (required version >= 6.3.1)
 * Qt6Widgets (required version >= 6.3.1)
 * Qt6OpenGLWidgets (required version >= 6.3.1)
 * Qt6Sql (required version >= 6.3.1)
 * Qt6Concurrent (required version >= 6.3.1)
 * Qt6ShaderToolsTools (required version >= 6.3.1)
 * Qt6ShaderTools (required version >= 6.3.1)
 * Python
 * Qt6Test (required version >= 6.3.1)
 * Qt6BuildInternals (required version >= 6.3.1)
 * WrapAtomic
 * Qt6CoreTools (required version >= 6.3.1)
 * Qt6Core (required version >= 6.3.1)
 * Qt6Network (required version >= 6.3.1)
 * Qt6Xml (required version >= 6.3.1)
 * EGL, A platform-agnostic mechanism for creating rendering surfaces for use with other graphics libraries, such as OpenGL|ES and OpenVG., <https://www.khronos.org/egl/>
 * GLESv2
 * PkgConfig
 * XKB (required version >= 0.5.0), XKB API common to servers and clients., <http://xkbcommon.org>
 * Qt6DBusTools (required version >= 6.3.1)
 * Qt6DBus (required version >= 6.3.1)
 * Qt6Gui (required version >= 6.3.1)
 * Qt6QmlTools (required version >= 6.3.1)
 * Qt6QmlModels (required version >= 6.3.1)
 * Threads
 * Qt6OpenGL (required version >= 6.3.1)
 * Qt6Quick (required version >= 6.3.1)
 * Qt6 (required version >= 6.3.1)
 * Qt6HostInfo
 * WrapIconv

-- The following OPTIONAL packages have not been found:

 * zstd
 * WrapZSTD (required version >= 1.3), ZSTD compression library, <https://github.com/facebook/zstd>
 * PCRE2
 * unofficial-brotli
 * double-conversion
 * WrapDoubleConversion
 * Libsystemd
 * Libb2
 * Slog2
 * Libproxy
 * GSSAPI, Generic Security Services Application Program Interface
 * harfbuzz (required version >= 2.6.0)
 * WrapSystemHarfbuzz (required version >= 2.6.0)
 * md4c
 * WrapSystemMd4c
 * Vulkan
 * WrapVulkanHeaders
 * GTK3 (required version >= 3.6)
 * DB2, IBM DB2 client library, <https://www.ibm.com>
 * MySQL, MySQL client library, <https://www.mysql.com>
 * Oracle, Oracle client library, <https://www.oracle.com>
 * ODBC
 * Qt6LanguageServerPrivate (required version >= 6.3.1)
 * Qt6LinguistTools (required version >= 6.3.1)
 * LTTngUST
 * Qt6QmlCompilerPlusPrivate


-- Configuration summary has been written to /home/shady/rpi/build/config.summary
-- Configure with --log-level=STATUS or higher to increase the output verbosity.
 
-- Configure summary:

Building for: linux-g++ (arm64, CPU features: cx16 neon)
Compiler: gcc 9.4.0
Build options:
  Mode ................................... release
  Optimize release build for size ........ no
  Fully optimize release builds (-O3) .... no
  Building shared libraries .............. yes
  Using C standard ....................... C11
  Using C++ standard ..................... C++17
  Using ccache ........................... no
  Using new DTAGS ........................ yes
  Relocatable ............................ yes
  Using precompiled headers .............. yes
  Using LTCG ............................. no
  Target compiler supports:
    Intrinsics without compiler architecture option  yes
    Extensions ........................... NEON
  Sanitizers:
    Addresses ............................ no
    Threads .............................. no
    Memory ............................... no
    Fuzzer (instrumentation only) ........ no
    Undefined ............................ no
  Build parts ............................ libs
Qt modules and options:
  Qt Concurrent .......................... yes
  Qt D-Bus ............................... yes
  Qt D-Bus directly linked to libdbus .... yes
  Qt Gui ................................. yes
  Qt Network ............................. yes
  Qt PrintSupport ........................ yes
  Qt Sql ................................. yes
  Qt Testlib ............................. yes
  Qt Widgets ............................. yes
  Qt Xml ................................. yes
Support enabled for:
  Using pkg-config ....................... yes
  udev ................................... yes
  Using system zlib ...................... yes
  Zstandard support ...................... no
  Thread support ......................... yes
Common build options:
  Linker can resolve circular dependencies  yes
Qt Core:
  backtrace .............................. yes
  DoubleConversion ....................... yes
    Using system DoubleConversion ........ no
  GLib ................................... yes
  ICU .................................... yes
  Using system libb2 ..................... no
  Built-in copy of the MIME database ..... yes
  cpp/winrt base ......................... no
  Tracing backend ........................ <none>
  Logging backends:
    journald ............................. no
    syslog ............................... no
    slog2 ................................ no
  PCRE2 .................................. yes
    Using system PCRE2 ................... yes
  CLONE_PIDFD support in forkfd .......... yes
Qt Sql:
  SQL item models ........................ yes
Qt Network:
  getifaddrs() ........................... yes
  IPv6 ifname ............................ yes
  libproxy ............................... no
  Linux AF_NETLINK ....................... yes
  OpenSSL ................................ yes
    Qt directly linked to OpenSSL ........ no
  OpenSSL 1.1 ............................ yes
  DTLS ................................... yes
  OCSP-stapling .......................... yes
  SCTP ................................... no
  Use system proxies ..................... yes
  GSSAPI ................................. no
  Brotli Decompression Support ........... yes
Core tools:
  Android deployment tool ................ no
  macOS deployment tool .................. no
  Windows deployment tool ................ no
  qmake .................................. yes
Qt Gui:
  Accessibility .......................... yes
  FreeType ............................... yes
    Using system FreeType ................ yes
  HarfBuzz ............................... yes
    Using system HarfBuzz ................ no
  Fontconfig ............................. yes
  Image formats:
    GIF .................................. yes
    ICO .................................. yes
    JPEG ................................. yes
      Using system libjpeg ............... yes
    PNG .................................. yes
      Using system libpng ................ yes
  Text formats:
    HtmlParser ........................... yes
    CssParser ............................ yes
    OdfWriter ............................ yes
    MarkdownReader ....................... yes
      Using system libmd4c ............... no
    MarkdownWriter ....................... yes
  EGL .................................... yes
  OpenVG ................................. no
  OpenGL:
    Desktop OpenGL ....................... no
    OpenGL ES 2.0 ........................ yes
    OpenGL ES 3.0 ........................ yes
    OpenGL ES 3.1 ........................ yes
    OpenGL ES 3.2 ........................ yes
  Vulkan ................................. no
  Session Management ..................... yes
Features used by QPA backends:
  evdev .................................. yes
  libinput ............................... yes
  HiRes wheel support in libinput ........ no
  INTEGRITY HID .......................... no
  mtdev .................................. yes
  tslib .................................. yes
  xkbcommon .............................. yes
  X11 specific:
    xlib ................................. yes
    XCB Xlib ............................. yes
    EGL on X11 ........................... yes
    xkbcommon-x11 ........................ yes
    xcb-sm ............................... yes
QPA backends:
  DirectFB ............................... no
  EGLFS .................................. yes
  EGLFS details:
    EGLFS OpenWFD ........................ no
    EGLFS i.Mx6 .......................... no
    EGLFS i.Mx6 Wayland .................. no
    EGLFS RCAR ........................... no
    EGLFS EGLDevice ...................... yes
    EGLFS GBM ............................ yes
    EGLFS VSP2 ........................... no
    EGLFS Mali ........................... no
    EGLFS Raspberry Pi ................... yes
    EGLFS X11 ............................ yes
  LinuxFB ................................ yes
  VNC .................................... yes
  VK_KHR_display ......................... no
  QNX:
    lgmon ................................ no
    IMF .................................. no
  XCB:
    Using system-provided xcb-xinput ..... no
    GL integrations:
      GLX Plugin ......................... no
        XCB GLX .......................... no
      EGL-X11 Plugin ..................... yes
  Windows:
    Direct 2D ............................ no
    Direct 2D 1.1 ........................ no
    DirectWrite .......................... no
    DirectWrite 3 ........................ no
Qt Widgets:
  GTK+ ................................... no
  Styles ................................. Fusion Windows
Qt Testlib:
  Tester for item models ................. yes
Qt PrintSupport:
  CUPS ................................... yes
Qt Sql Drivers:
  DB2 (IBM) .............................. no
  InterBase .............................. yes
  MySql .................................. no
  OCI (Oracle) ........................... no
  ODBC ................................... no
  PostgreSQL ............................. yes
  SQLite ................................. yes
    Using system provided SQLite ......... no
Qt QML:
  QML network support .................... yes
  QML debugging and profiling support .... yes
  QML just-in-time compiler .............. yes
  QML sequence object .................... yes
  QML XML http request ................... yes
  QML Locale ............................. yes
Qt QML Models:
  QML list model ......................... yes
  QML delegate model ..................... yes
Qt Quick:
  AnimatedImage item ..................... yes
  Canvas item ............................ yes
  Support for Qt Quick Designer .......... yes
  Flipable item .......................... yes
  GridView item .......................... yes
  ListView item .......................... yes
  TableView item ......................... yes
  TreeView item .......................... yes
  Path support ........................... yes
  PathView item .......................... yes
  Positioner items ....................... yes
  Repeater item .......................... yes
  ShaderEffect item ...................... yes
  Sprite item ............................ yes
Qt Quick Templates 2:
  Hover support .......................... yes
  Multi-touch support .................... yes
  Calendar support ....................... yes
Qt Quick Controls 2:
  Styles ................................. Basic Fusion Imagine Material Universal macOS Windows
Qt 5 Compatibility Libraries:
  iconv .................................. no
 

-- 

Qt is now configured for building. Just run 'cmake --build . --parallel'

Once everything is built, you must run 'cmake --install .'
Qt will be installed into '/usr/local/qt6'

To configure and build other Qt modules, you can use the following convenience script:
        /home/shady/rpi/install/bin/qt-configure-module

If reconfiguration fails for some reason, try removing 'CMakeCache.txt' from the build directory 

-- Configuring done
-- Generating done
-- Build files have been written to: /home/shady/rpi/build

```ter item .......................... yes
  ShaderEffect item ...................... yes
  Sprite item ............................ yes
Qt Quick Templates 2:
  Hover support .......................... yes
  Multi-touch support .................... yes
  Calendar support ....................... yes
Qt Quick Controls 2:
  Styles ................................. Basic Fusion Imagine Material Universal macOS Windows
Qt 5 Compatibility Libraries:
  iconv .................................. no
 

-- 

Qt is now configured for building. Just run 'cmake --build . --parallel'

Once everything is built, you must run 'cmake --install .'
Qt will be installed into '/usr/local/qt6'

To configure and build other Qt modules, you can use the following convenience script:
        /home/shady/rpi/install/bin/qt-configure-module

If reconfiguration fails for some reason, try removing 'CMakeCache.txt' from the build directory 

-- Configuring done
-- Generating done
-- Build files have been written to: /home/shady/rpi/build

And here is the failure:

FAILED: qtbase/lib/libQt6DBus.so.6.3.1 qtbase/src/dbus/DBus.version /home/shady/rpi/build/qtbase/src/dbus/DBus.version 
cd /home/shady/qt6source/qtbase/src/dbus && /usr/bin/perl /home/shady/qt6source/qtbase/mkspecs/features/data/unix/findclasslist.pl < /home/shady/rpi/build/qtbase/src/dbus/DBus.version.in > /home/shady/rpi/build/qtbase/src/dbus/DBus.version && cd /home/shady/rpi/build && /usr/bin/aarch64-linux-gnu-g++-9 --sysroot=/home/shady/rpi/piOSsysroot -fPIC -I/home/shady/rpi/piOSsysroot/usr/include -pipe -O2  -Wl,-O1 -Wl,--hash-style=gnu -Wl,--as-needed -ldbus-1   -Wl,--version-script,/home/shady/rpi/build/qtbase/src/dbus/DBus.version -Wl,--no-undefined -Wl,--enable-new-dtags -shared -Wl,-soname,libQt6DBus.so.6 -o qtbase/lib/libQt6DBus.so.6.3.1 qtbase/src/dbus/CMakeFiles/DBus.dir/DBus_autogen/mocs_compilation.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbus_symbols.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusabstractadaptor.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusabstractinterface.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusargument.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusconnection.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusconnectioninterface.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbuscontext.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbuserror.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusextratypes.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusintegrator.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusinterface.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusinternalfilters.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusintrospection.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusmessage.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusmetaobject.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusmetatype.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusmisc.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbuspendingcall.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbuspendingreply.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusreply.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusserver.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusservicewatcher.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusunixfiledescriptor.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusutil.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusvirtualobject.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusxmlgenerator.cpp.o qtbase/src/dbus/CMakeFiles/DBus.dir/qdbusxmlparser.cpp.o  -Wl,-rpath,/home/shady/rpi/piOSsysroot:/home/shady/rpi/build/qtbase/lib:  /home/shady/rpi/piOSsysroot/usr/lib/aarch64-linux-gnu/libdbus-1.a  qtbase/lib/libQt6Core.so.6.3.1  -lpthread && :
/usr/lib/gcc-cross/aarch64-linux-gnu/9/../../../../aarch64-linux-gnu/bin/ld: /home/shady/rpi/piOSsysroot/usr/lib/aarch64-linux-gnu/libdbus-1.a(libdbus_1_la-dbus-message.o): relocation R_AARCH64_ADR_PREL_PG_HI21 against symbol `dbus_message_unref' which may bind externally can not be used when making a shared object; recompile with -fPIC
/home/shady/rpi/piOSsysroot/usr/lib/aarch64-linux-gnu/libdbus-1.a(libdbus_1_la-dbus-message.o): in function `_dbus_message_loader_unref':
(.text+0x59d8): dangerous relocation: unsupported relocation
/usr/lib/gcc-cross/aarch64-linux-gnu/9/../../../../aarch64-linux-gnu/bin/ld: /home/shady/rpi/piOSsysroot/usr/lib/aarch64-linux-gnu/libdbus-1.a(libdbus_1_la-dbus-timeout.o): relocation R_AARCH64_ADR_PREL_PG_HI21 against symbol `_dbus_timeout_unref' which may bind externally can not be used when making a shared object; recompile with -fPIC
/home/shady/rpi/piOSsysroot/usr/lib/aarch64-linux-gnu/libdbus-1.a(libdbus_1_la-dbus-timeout.o): in function `_dbus_timeout_list_free':
(.text+0x130): dangerous relocation: unsupported relocation
/usr/lib/gcc-cross/aarch64-linux-gnu/9/../../../../aarch64-linux-gnu/bin/ld: /home/shady/rpi/piOSsysroot/usr/lib/aarch64-linux-gnu/libdbus-1.a(libdbus_1_la-dbus-watch.o): relocation R_AARCH64_ADR_PREL_PG_HI21 against symbol `_dbus_watch_unref' which may bind externally can not be used when making a shared object; recompile with -fPIC
/home/shady/rpi/piOSsysroot/usr/lib/aarch64-linux-gnu/libdbus-1.a(libdbus_1_la-dbus-watch.o): in function `_dbus_watch_list_free':
(.text+0x1b0): dangerous relocation: unsupported relocation
/usr/lib/gcc-cross/aarch64-linux-gnu/9/../../../../aarch64-linux-gnu/bin/ld: /home/shady/rpi/piOSsysroot/usr/lib/aarch64-linux-gnu/libdbus-1.a(libdbus_1_la-dbus-sysdeps-unix.o): in function `_dbus_listen_systemd_sockets':
(.text+0x204c): undefined reference to `sd_listen_fds'
/usr/lib/gcc-cross/aarch64-linux-gnu/9/../../../../aarch64-linux-gnu/bin/ld: (.text+0x2090): undefined reference to `sd_is_socket'
/usr/lib/gcc-cross/aarch64-linux-gnu/9/../../../../aarch64-linux-gnu/bin/ld: /home/shady/rpi/piOSsysroot/usr/lib/aarch64-linux-gnu/libdbus-1.a(libdbus_1_la-dbus-userdb.o): relocation R_AARCH64_ADR_PREL_PG_HI21 against symbol `_dbus_group_info_unref' which may bind externally can not be used when making a shared object; recompile with -fPIC
/home/shady/rpi/piOSsysroot/usr/lib/aarch64-linux-gnu/libdbus-1.a(libdbus_1_la-dbus-userdb.o): in function `_dbus_user_database_new':
(.text+0x4e8): dangerous relocation: unsupported relocation
collect2: error: ld returned 1 exit status
[605/4156] Building C object qtbase/sr...r/__/__/__/3rdparty/sqlite/sqlite3.c.o
ninja: build stopped: subcommand failed.

Any insight or help would be appreciated!!! Please let me know if you need more information.

adazem009

From known issues in https://wiki.qt.io/Cross-Compile_Qt_6_for_Raspberry_Pi:

This could happen when the libdbus inside the initial sysroot is not a dynamically shared objects. This is normally fixable by doing a clean reinstall of Raspberry Pi OS (reformat microSD card, then install Raspberry Pi OS again through the Imager). Another recommendation is to try to reinstall libdbus-1-dev package. But if the problem persists and you don't need dbus, you can disable the dbus feature by adding -DFEATURE_dbus=OFF flag in the CMake configuration command.

Another walkaround worth trying is to change

from:

set(QT_LINKER_FLAGS "-Wl,-O1 -Wl,--hash-style=gnu -Wl,--as-needed")

to:

set(QT_LINKER_FLAGS "-Wl,-O1 -Wl,--hash-style=gnu -Wl,--as-needed -ldbus-1")

Additionally make sure that link to rpi-sysroot/usr/lib/aarch64-linux-gnu/libdbus-1.so is valid. It should be linking to libdbus-1.so.3.19.13 in the same directory.

Note: You'll need DBus to have Bluetooth module working.

srini_durand

Broken Link in sysroot/usr/lib/aarch64-linux-gnu/libdbus-1 just fix the symbolic link and away you go.