It is impossible to have clean rpath without explicit use of linkerFlags

I want to build a binary which have exactly one rpath $ORIGIN/../lib.
For that I should write

cpp.rpaths: ["$ORIGIN/../lib"]

However QBS forces two another entries which could not be disabled:
$ORIGIN from share/qbs/modules/cpp/LinuxGCC.qbs and Qt libPath from core.qbs of QtCore module.
To work around this I have to disable cpp.useRPaths and fall back to cpp.linkerFlags.

I think QBS should not implicitly fill this property.