This tutorial describes setting up Coverage Validator to include or exclude different source files from coverage processing when you dynamically link your application with MFC and/or the C Runtime.
When you dynamically link to MFC and the CRT, the code for MFC and the CRT is held in separate DLLs to your application. This allows you to specify not to process MFC or CRT code by simply indicating which DLLs not to process – you don’t need to know where the source code for those DLLs is.
You have learned how to customize the C runtime, MFC, STL and Win32 DLLs that will be considered for code coverage.
The default is to not process any of these DLLs, but if you wish to override that default you know how to do it.