Including references from x86 or "Any CPU" to other assemblies in Visual Studio 2008

Question

It seems that if I have a .NET assembly that is going to be loaded by some unmanaged "x86" code, running on a 64bit O/S (e.g. Vista), then I need to compile that .NET assembly with the .x86 Solution Platform.

What about other .NET assemblies that my original assembly references? Are they allowed to be "Any CPU" assemblies? Or must they also be compiled with x86?

As I write this I am guessing the answer to the last question must be "No", because otherwise all the Microsoft assemblies (for example) would need to be provided in "x86" and "Any CPU" and "x64" flavours, and somehow that seems very "Bad Form, Peter" (as Captain Hook would say).

Short of trying it out (which is difficult because I don't have a 64 bit PC near at hand), can anyone put me out of my misery?

Answer 1

I've finally managed to test it, and my guess that I put forward in the question was correct.

(By the way, I should have used the word "Build" instead of "Compile", as the assemblies only get compiled when they're run).