Developing Drivers with the Windows® Driver Foundation

How to Write and Debug Annotations

Many annotations are straightforward and obvious to write, but some can take a little effort to get right. PREfast attempts to diagnose any errors it sees in annotations, but it cannot check and report every conceivable error. It is always a good idea to write a small test case to confirm that annotations behave as you expect.

A good test case should report any expected errors and should not report instances of correct usage. Simple annotations such as __in do not benefit from test cases, but annotations that involve sizes—in particular, annotations that use the __part modifier—often benefit from test cases because writing the test cases often forces you to think about corner cases.

Examples of Annotation Test ...