Qt building from sources - xcb dependencies

MasterQ

@SGaist said in Qt building from sources - xcb dependencies:

Which distribution are you using ?

I am using Opensuse Tumbleweed

@JoeCFD said in Qt building from sources - xcb dependencies:

@MasterQ It is likely that some libs are missing for plugins.
export QT_DEBUG_PLUGINS=1
to find out which plugins can not be loaded. Install their dependencies.

I know the missing plugins. But I cannot find them in my package manager. They are not listet. Maybe they are named differently, I don't know.

I got no suitable answer so far from the Opensuse community. I am still trying.

BTW.:

the env variable gets no hint about the missing xcb. Since I am building Qt from source, the xcb components are not found already at build time. Even if the configure summary states xcb ... yes, some components are missing and xcb seems not to be included in the build. It is not listet as available:

This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: eglfs, wayland-egl, linuxfb, vnc, offscreen, minimal, vkkhrdisplay, wayland, minimalegl.

jsulm

@MasterQ said in Qt building from sources - xcb dependencies:

I know the missing plugins.

It's not about missing plug-ins, it's about missing dependencies for plug-ins. You should really follow the advice using QT_DEBUG_PLUGINS to see what is missing...

"This application failed to start because no Qt platform plugin could be initialized" - please follow QT_DEBUG_PLUGINS advice so we can see what is missing to be able to load this plug-in.

MasterQ

starting my program with QT_DEBUG_PLUGINS=1 gives the following output.

qt-debug-plugins.txt

Since the post is marked as spam when I insert the output, I have to go via google drive and to provide a download link instead.

Attachements are not available here?

jsulm

@MasterQ I can't open this file. Please take a closer look at its content, especially where the platform plug-in is loaded. You should find more details about what is missing.

MasterQ

@jsulm said in Qt building from sources - xcb dependencies:

@MasterQ I can't open this file.

I see. If you click on the link a browser should open and show the file as an image. I tried again to insert here as text, but it is marked as spam again, whyever.

please click on the link, do not try to save the target or similar. By clicking on the link your browser is opening a frame. From there you can download.

Here another attemp via my own nextcloud

qt_debug_plugins.txt

I had a closer look already. In the file there are no hints about any missing items. xcb is not even mentioned.

SGaist

That is the thing: it was not built due to missing development packages of the dependencies listed as missing that you posted earlier.

MasterQ

I know, that's what I already said.

I followed that list

Qt for X11 Requirements

and made a checkmark on every listet item. Nevertheless, configure is claiming about missing xcb components and a built program is not starting.

I also got no helpful reply from Opensuses community.

I am now working on switching to Wayland and to skip X11. With Wayland there are no issues so far.

jsulm

@MasterQ said in Qt building from sources - xcb dependencies:

Nevertheless, configure is claiming about missing xcb components and a built program is not starting.

@Christian-Ehrlicher Already wrote that libs are missing - did you address that?
Here:

-- [QtBase] Could NOT find XCB_EWMH (missing: XCB_EWMH_LIBRARY XCB_EWMH_INCLUDE_DIR) (found version "")
-- [QtBase] Could NOT find XCB_ICCCM (missing: XCB_ICCCM_LIBRARY XCB_ICCCM_INCLUDE_DIR) (found version "")
-- [QtBase] Could NOT find XCB_KEYSYMS (missing: XCB_KEYSYMS_LIBRARY XCB_KEYSYMS_INCLUDE_DIR) (found version "")
-- [QtBase] Could NOT find XCB_XEVIE (missing: XCB_XEVIE_LIBRARY) (found version "")
-- [QtBase] Could NOT find XCB_XPRINT (missing: XCB_XPRINT_LIBRARY) (found version "")

MasterQ

@Christian-Ehrlicher Already wrote that libs are missing - did you address that?

Yes. After post #2 of this thread I checked everything again and installed devel packages as long as they were available.

I now have reinstalled/changed whole OS. After already spending too much time on that issue, a complete new install yesterday was much faster and easier. The journey is still not at its end but for now it is looking promissing.

Maybe today or tomorrow I will see if Qt configures and compiles.

jsulm

@MasterQ said in Qt building from sources - xcb dependencies:

Yes. After post #2 of this thread I checked everything again and installed devel packages as long as they were available

But did you also build and install the XCB plug-in afterwards?

MasterQ

Yes, of course. .. I tried at least and failed.

I am now running a fresh OS and it seems the xcb issues are gone. But others arise. Configure says

joachim:~/Qt$ grep "NOT find" configure.log
-- [QtBase] Could NOT find Slog2 (missing: Slog2_INCLUDE_DIR Slog2_LIBRARY) 
-- [QtBase] Could NOT find GSSAPI (missing: GSSAPI_LIBRARIES GSSAPI_INCLUDE_DIRS) 
-- [QtBase] Could NOT find EGL (missing: HAVE_EGL) (found version "1.5")
joachim:~/Qt$

All dependencies could be solved except of the mentioned above. At the moment I can not identify corresponding libs.

for pattern slog2 I get no hit
for pattern gssapi I get several hits, like
libglobus-gssapi-assist-devel
libglobus-gssapi-error-devel
...

for pattern egl I get
gegl
glgrib-egl

Any idea how the missing libs are called?

The System now is an Ubuntu 2410.

jsulm

Well, if everything you need is enabled you can ignore these missing parts.

MasterQ

ignoring the missing dependencies is difficult since configure stopps.

-- [QtBase] Could NOT find EGL (missing: HAVE_EGL) (found version "1.5")
-- Configuring incomplete, errors occurred!

GSSAPI could now be identified with libkrb5-dev (1.21.3-3)

FindEGL.cmake is looking for EGL/egl.h which can be found in libegl-dev and in package emscripten. Even if libegl-devel is installed, it is not found.

FindSlog2.cmake is looking for /sys/slog2.h which is not found in any package.

To which Qt parts do EGL and Slog2 refere to? I then can decide if I can ignore or skip that modules.

jsulm

@MasterQ said in Qt building from sources - xcb dependencies:

To which Qt parts do EGL

QtBase, you can see that in the configure output ([QtBase]).
Not sure about slog.

After installing missing dependencies you should start from scratch:

Delete build folder
Create new build folder
Run cmake

MasterQ

Hi,

last update!

After a break due to broken hardware I have started from scratch and now all is running fine.

It seems that I previoulsy had used (by accident) an outdated compiler, gcc-7 instead of gcc-14.