- Do not have MinGW in your PATH variable.
- Install MinGW 5.3.0 as well as a Qt built for it using Qt's online installer.
- Start Creator with empty settings, e.g. by passing the parameter -settingspath <empty directory>.
- In "Tools" -> "Options..." -> "Build & Run" -> "Qt Versions", add the Qt version you installed in step 2.
Creator will complain that there is no compiler for this Qt version.
- On the compiler tab, add gcc and g++ from the MinGW you installed in step 2.
Their ABIs are detected as x86-windows--pe-, which is totally wrong.
- Click "Apply" and go back to the "Qt Versions" tab.
The warning about missing compilers is gone.
- Add a kit using the now configured compilers and Qt version.
You'll see a warning that the compilers do not match the Qt version. The truth there is that the Qt version does not match the detected ABI whereas the compilers themselves are matching.
- The ABI of MinGW compilers should be detected correctly.
- The warnings about non-matching compilers should be consistent on the "Kits" and "Qt Versions" tabs.