How to run qsb from Visual Studio custom build step

[Johan_R]

I'm developing a Qt application. I am using Qt 6.4.2, Visual Studio 2019 and the Qt Visual Studio Tools. I'm not using QMake or CMake. I tried to create a custom build step for baking shaders. Here is what I came up with:

The file BakeShaders.bat just contains the command

%QT_DIR%\bin\qsb  --glsl 100es,120,150  --hlsl 50  --msl 12  -o Shaders\SvgButton.frag.qsb  Shaders\SvgButton.frag

This sometimes works. But often the build fails with the error message

Qt::BuildLock[{CC143C7A-D81C-4243-A5FE-2B5CFBA01776}]: Timeout; wait aborted

How do I set up a custom build step that works?

Thank you
Johan Råde