CLSCompliant(true) drags in unused references

Question

Can anyone explain the following behavior?

In summary, if you create multiple CLS compliant libraries in Visual Studio 2008 and have them share a c

Answer 1

I had a look into the official documents for the CLS (http://msdn.microsoft.com/en-us/netframework/aa569283.aspx), but my head exploded before I could find a simple answer.

But I think the basis is that the compiler, in order to verify the CLS compliance of LibraryC, needs to look into possible naming conflicts with LibraryA.

The compiler must verify all "parts of a type that are accessible or visible outside of the defining assembly" (CLS Rule 1).

Since public class Class1InLibraryC inherits Class2InLibraryB, it must verify the CLS compliance against LibraryA as well, in particular because "Ploeh.*" is now "in scope" for CLS Rule 5 "All names introduced in a CLS-compliant scope shall be distinct independent of kind".

Changing either the namespace of Class1InLibraryB or Class1InLibraryC so they become distinct seems to convince the compiler there is no chance for a name conflict anymore.

If you choose option (2), add the reference and compile, you'll see that the reference is not actually marked in the resulting assembly meta-data, so this is a compilation/verification-time dependency only.