src/Viewer/studio3d/q3dsdatainput.h is included in various runtime sources, even though it is part of studio3d module, which itself depends on runtime -> so runtime should not depend on anything in there or that could be considered a circular dependency. Why it works at all is that runtime only uses enums from the header. However, the fact that runtime includes q3dsdatainput.h forces q3dsdatainput.h itself have incorrect include:

#include "qstudio3dglobal.h" 

The correct way to include this header in q3dsdatainput.h would be the following, but it doesn't compile on CI currently, because the header is included from runtime:

#include <QtStudio3D/qstudio3dglobal.h>