Qt6 packages seem to be missing pkg-config files

[Peter Rockett]

The qt6-base-dev package is missing the pkg-config .pc files (that do exist in the corresponding Debian packages and also existed in the Qt5 version of this package). The result is that building gnuplot 6 breaks, for example.

(Thought I had filed this already bu can find no mention.)

P.

[Rik Mills (rikmills)]

What version of Qt6 in Ubuntu is missing the .pc files? And in what Ubuntu release? Also what version in of qt6-base-dev in Debian are you saying has them?

[Peter Rockett (p-rockett-2)]

qt6-base-dev 6.2.4+dfsg-2ubuntu1 (amd64 binary) in ubuntu jammy

Debian version: see https://packages.debian.org/bookworm/amd64/qt6-base-dev/filelist

I still have the qt5-base-dev files left on my machine and I can see a whole collection of files: Qt5Concurrent.pc, Qt5Network.pc, Qt5Sql.pc Qt5Xml.pc, Qt5Core.pc, Qt5OpenGLExtensions.pc, Qt5Svg.pc, Qt5DBus.pc, Qt5OpenGL.pc, Qt5Test.pc, Qt5Gui.pc, Qt5PrintSupport.pc and Qt5Widgets.pc in /usr/lib/x86_64-linux-gnu/pkgconfig. There are no corresponding files for Qt6 which causes, for example, the build of gnuplot 6 to break. (I have confirmed with the gnuplot maintainer that the problem is the missing .pc files.)

[Sebastien Bacher (seb128)]

We also got a request from libcamera to fix that issue in 22.O4, for context
https://lists.libcamera.org/pipermail/libcamera-devel/2024-April/041498.html

> Oh, I know what's wrong: there are no pkgconfig files for Qt 6 in Ubuntu 22.04.

> This was fixed in 6.2.5, but it hasn't been backported to Ubuntu's
> package: https://codereview.qt-project.org/gitweb?p=qt/
qtbase.git;a=commit;h=205ec2bb36b0a52d0dfa6729876eb18bcdbef512

So I think the request is to SRU that fix or update to 6.2.5

[Rik Mills (rikmills)]

Updating qtbase to 6.2.5 is not feasible as that involves an ABI bump even for point releases. The entire Qt stack would need updating to 6.2.5, plus rebuilds of reverse dependencies of the old ABI.

So we are looking at applying/backporting this patch from the aforementioned upstream MP.

https://code.qt.io/cgit/qt/qtbase.git/commit/?h=6.2&id=205ec2bb36b0a52d0dfa6729876eb18bcdbef512

[Rik Mills (rikmills)]

Fixing this issue in qt6-base is likely to be of only very limited benefit if .pc file are missing from the development packages of the other source in the Qt6 stack.

A quick list of possible affect sources that might need patching or rebuild is:

qt6-3d
qt6-5compat
qt6-charts
qt6-connectivity
qt6-datavis3d
qt6-declarative
qt6-imageformats
qt6-lottie
qt6-multimedia
qt6-networkauth
qt6-positioning
qt6-quick3d
qt6-quicktimeline
qt6-remoteobjects
qt6-scxml
qt6-sensors
qt6-serialbus
qt6-serialport
qt6-shadertools
qt6-svg
qt6-tools
qt6-translations
qt6-virtualkeyboard
qt6-wayland
qt6-webchannel
qt6-webengine
qt6-websockets
qt6-webview