QT 6.8.1 QPA plugin version mismatch

[Rukshan Perera]

I am trying to run a qt application I built. I am getting warning about missing qpa plugins. Then I installed qt6-qpa-plugins via apt get. Then used

export QT_QPA_PLATFORM_PLUGIN_PATH=/usr/lib/x86_64-linux-gnu/qt6/plugins

But I am seeing

qt.core.plugin.factoryloader: Ignoring QPA plugin due to mismatching Qt versions 395264 393728

When I tried to build qt6.8.1 locally I also get an error

src/plugins/hardwareintegration/compositor/hardwarelayer/vsp2/main.cpp:12:1: error: Parse error at "IID"
make: *** [Makefile:26592: main.moc] Error 1

I also added the same question to stackoverflow. Any idea how to approach this problem?
I am using.

Distributor ID:	Ubuntu
Description:	Ubuntu 22.04.5 LTS
Release:	22.04
Codename:	jammy

[ChrisW67]

You are mixing Qt versions, probably the default Qt 5.15.x installed system-wide in Ubuntu 22.04 and a Qt version installed locally using the online installer (6.x, but we can only guess).

[hskoglund]

You can see the 2 versions in the error message "...due to mismatching Qt versions 395264 393728"
Converted to hexadecimal they decode as 6.8.x and 6.2.x

[Rukshan Perera]

Okay thanks. I think I have installed 6.2.x via sudo apt install qt6-qpa-plugins. I guess I need to find 6.8.x version

[jsulm]

@Rukshan-Perera said in QT 6.8.1 QPA plugin version mismatch:

When I tried to build qt6.8.1 locally

How did you install it?