Uncomfortable difference between machine libraries and SDK libraries

Question

I have this situation:

• I'm working on a device with my yocto (pyro) distribution. The device works properly.
• Sdk generated with

  bitbake -c populate_sdk myimagename-sdk

• Qt Creator kit added like in the instructions: http://doc.qt.io/qtcreator/creator-targets.html

Using Qt Creator (when debugging and running) it warn me about the absence of some libraries.

Unable to find dynamic linker breakpoint function. GDB will be unable to debug shared library initializers and track explicitly loaded dynamic code.Could not load shared library symbols for 22 libraries, e.g. /usr/lib/libQt5Quick.so.5. Use the "info sharedlibrary" command to see the complete listing. Do you need "set solib-search-path" or "set sysroot"?

I temporarily solved the problem by copying the libraries located on the device in /lib and /usr/lib into a folder called sysroot and set the qtcreator debugger by adding : set sysroot /home/user/sdkroot/sysroot.

To avoid my temporary solution it is possible, when compiling sdk, to include all the libraries (including those that go to the device)?

I searched for settings for the local.conf or *.bb includes without finding anything useful.

Thanks in advance and excuse my English

---

EDIT

I tried to "use the "info sharedlibrary" command to see the complete listing" (as suggested by qtcreator), for a very simple program, following these steps:

device side

• gdbserver --multi :1000

pc side

• ./arm-poky-linux-gnueabi-gdb #to start the gdb of my toolchain
• target extended-remote 192.168.77.1:10000
• run /tmp/myapp #previously deployed by qtcreator
• file ~/sdk/example/build-myapp-kit_device-Debug/myapp #load symbol table
• break 44 #breakpoint at line 44
• run
• info sharedlibrary

This is the list I get:

/usr/lib/libQt5Core.so.5; /usr/lib/libstdc++.so.6; /lib/libgcc_s.so.1; /lib/libc.so.6; /lib/libthread.so.0; /lib/libz.so.1; /usr/lib/libicui18n.so.53; /usr/lib/libicuuc.so.53; /lib/librt.so.1; /lib/libm.so.6; /lib/ld-linux-armhf.so.3

These are libraries that are already in the sysroot of my toochain (which I linked in "sysroot" in the qtcreator kit). And by doing a binary comparison, the result is that they are identical to the libraries I picked up from the device and that I added in qtcreator (as mentioned above: set sysroot /home/user/sdkroot/sysroot)

If the libraries my apps are requesting are already in the toolchain's sysroot, why do I still have to add them from the device?

Answer 1

Instead of bitbake -c populate_sdk myimagename-sdk

you should use bitbake meta-toolchain-qt5 This will include all the qt5-dev and qt5-mkspec as well as others path configuration into your toolchain;

You could also copy and paste the stuff in the meta-toolchain-qt5 recipe to your sdk.

recipe is here: https://github.com/meta-qt5/meta-qt5/blob/master/recipes-qt/meta/meta-toolchain-qt5.bb

Answer 2

Building an image based SDK should give you all the libries in the actual image.

In the case of Qt5, your image should incluce:

inherit populate_sdk_qt5

That should ensure that you get Qt5 in your SDK, when you run bitbake -c populate_sdk myimagename. Note, you should be able to use your normal image here.

Also worth noting, that there are a regression currently in Pyro, which causes some libraries header files to be missing from the SDK (this doesn't apply to Qt5, though).

Answer 3

You can find information here on setting up Qtcreator to cross compile for Embedded Linux. Two three things are specific to the concerned company link but otherwise pretty generic.