since this version 2.1.0 qtcreator executes (or at least displays..) the "make clean" output twice, both Windows and Linux, independent of the qt version itself, tried with 4.7.1 and 4.7.2. The previous qtcreator 2.0.1 perfectly works on both OS's, with any qt version. On Windows(7) the "make clean" is hanging afterwards, and it takes quite a while to indicate the build is finished, nothing alike under Linux. The described effect is also independently of using -j8 (in my case..) for "make" or "jom.exe" to execute multiple "make" jobs concurrently. It is also independently of whether using "Clean All", or just "Clean Project x". But on a "Rebuild" of any kind all works fine, just 1 single execution of the "make clean" step.