Precompiled headers with webassembly

[Trigve]

Hi,
when trying to build the webassembly project with qmake with precompiled headers on windows, there is an error like:

shared:ERROR: debug_qt\clientQt.js.pch\c++.pch: Input file has an unknown suffix, don't know what to do with it!

As I found out, the problems is probably with -Xclang -include-pch -Xclang debug_qt\clientQt.js.pch\c++.pch used in em++ command:

em++ -c -Xclang -include-pch -Xclang debug_qt\clientQt.js.pch\c++.pch  ...

If I replace the -X flags with -include-pch debug_qt\clientQt.js.pch\c++.pch then everything looks ok. Could it be that the qmake generate wrong flags for em++?