[Qt-creator] 5.8/4.2.1 iOS Build fails first time

[ekke]

while moving all my projects from 5.7 to 5.8 I noticed a strange behavior.

doing a first build/run on iOS fails:

Code signing is required for product type 'Application' in SDK 'iOS 10.2'

to make it run: open generated XCode project once with XCode

then all following build/run from QtC are working

all required info for signing is inside .pro

don't know if this is expected behavior because of XCode or not

to explain details better I have opened
https://bugreports.qt.io/browse/QTCREATORBUG-17832

thx for any infos

ekke