Compilation fails with "Makefile:174: recipe for target 'sub-tools-make_first-ordered' failed" error
Created attachment 402952 [details] emerge --info '=dev-qt/qt-creator-9999::qt' output
Created attachment 402954 [details] build log
I see you are also using qt-5.9999... could be that you're using a too new version of qt and qt-creator hasn't been updated to build with it yet. In any case this is all very bleeding edge and to be expected from live ebuilds. IOW, given the lack of manpower, I'm not going to spend time on this unless it's still reproducible with qt-creator-3.5.0_beta (when it is released), and with a released version of qt (e.g. 5.4.x) Or you can find the cause yourself and provide a patch.