The platforms supported by Qt are divided into the following categories:

Actively supported platforms

Trolltech engineers work on those platforms to develop and test the products continuously.

All releases are supposed to work on those platforms out-of-the-box. If a release does not work on such a platform it is a bug which Trolltech will fix for the next maintenance release.

The actively supported platforms are listed on the Supported platforms page.

Community-supported platforms

Trolltech will try to incorporate compilation and bug fixes for these platforms but makes no guarantees for out-of-the box functionality.

Community supported platforms are not tested internally at Trolltech.

LLVM is one such platform.

Unsupported platforms

Trolltech has no access to those platforms, and will not make changes to released code to make products work. However, contributions will be considered on a case-by-case basis.