WSL: QT application fails to start

Question

I have compiled a simple QT Quick application (using Ruby-Qml, but I don't think this matters) on Ubuntu (18.04) via WSL on Windows 10 v1903 and get the following error when launching with Xming.

QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-xxxx'
failed to get the current screen resources
WARNING: Application calling GLX 1.3 function "glXCreatePbuffer" when GLX 1.3 is not supported!  This is an application bug!
QGLXContext: Failed to create dummy context

Any ideas how to resolve this?

What version of Windows 10 are you using? Please provide your exact build as an edit to your question. — Ramhound, Nov 16 '19 at 22:07
In order to run QT Quick you will have to upgrade to 1909 and use use a WSL 2 instance — Ramhound, Nov 16 '19 at 22:26
Thanks! I will wait another two weeks if 1909 is ready for the masses and then take the jump. I read some pointers about `vcxsrv` being a potential solution. What is your take on that? — Christopher Oezbek, Nov 16 '19 at 22:29
Why struggle trying to do something the original version of WSL wasn't designed to support? — Ramhound, Nov 16 '19 at 22:36

score 7 · Answer 1 · answered Nov 16 '19 at 22:55

7

For those still on Windows 10 v1903:

Change from xming to vcxsrv
If on a HighDPI screen change compatibility settings to let the application handle DPI scaling.
Start vcxsrv without support for OpenGL indirection (-nowgl) and ensure that LIBGL_ALWAYS_INDIRECT is unset (export LIBGL_ALWAYS_INDIRECT=)

answered Nov 16 '19 at 22:55

Christopher Oezbek

257
1
3
15

> and ensure that `LIBGL_ALWAYS_INDIRECT` is unset (`export LIBGL_ALWAYS_INDIRECT=`) This is what I was missing, and what worked for me, thanks! – Youw Jul 27 '21 at 14:41

score 1 · Answer 2 · answered Nov 16 '19 at 22:39

I have compiled a simple QT Quick application (using Ruby-Qml, but I don't think this matters) on Ubuntu (18.04) via WSL on Windows 10 v1903 and get the following error when launching with Xming.

Any ideas on how to resolve this?

The original version of WSL was not designed to run applications with a graphical UI. There are ways around this by remoting into the instance with say Xming, but those solutions, don't always work as you have found.

The simplest solution is to migrate to a WSL 2 instance, Windows 10 version 1909 is the first version that supports WSL 2, which run an actual Linux kernel.

The simplest solution would be to upgrade to Windows 10 version 1909 since it's considered a cumulative update to Windows 10 version 1903, it should be just as stable as Windows 10 version 1903.

Yes; While Windows 10 version 1909 is a feature update, it is running the same build (except incremented by 1) as Windows 10 version 1903.

WSL: QT application fails to start

2 Answers2