The default order of compile multiple sub-projects

[Three-Body]

I have multiple sub-projects in one of my QT projects. If I don't set CONFIG += ordered in the pro file, and I don't use SUBDIRS to set compilation dependencies, what rules does Qt use by default to determine the compilation order of subprojects?

[jsulm]

@Three-Body You posted in English in Chinese forum. Please use correct forum.

I think if you do not define dependencies between the projects the order will be undefined and on multi-core and/or multi-cpu machines they will be built in unspecified and probably non-reproducible order.