How to force Qt Creator to use MinGW instead of Visual Studio

We're trying to compile a project with MinGW on the machine that has both MinGW (with Qt) and Visual Studio installed. Unfortunately, Qt creator prefers MSVS by default, and doesn't see it's very own MinGW (screenshot). Sadly, this results in a lot of obscure errors, because开发者_高级运维 application was written and debugged with MinGW. Is there way to make Qt Creator to use MinGW without killing MSVS?

While installing, choose custom type of installation. Selected libraries for needed compilers in QtSDK->Development Tools->Desktop Qt->Qt-. Screenshot:

Have you made sure your Qt sdk is installed with its MinGW? You can use the Qt maintainance app to make sure its MinGW engine is installed.

Where are those libraries from? Did you compile the SDK yourself? Or did you downloded the libraries?

Try to see what is in the mkspecs directory. There should be a link named 'default'. That links to the specification which is being used. I suppose it is pointing to win32-msvc2008. You can change that but if it is pointing to that specification it means that the Qt libraries have been compiled with that specification (unless it was changed afterwards), which means you cannot use those with MinGW. You should compile the libraries with the correct specification or download the correct package (MinGW version).