It appears that, in VB, you will be unable to create the requisite Attribute unless you have "no root namespace".
Now that's annoying. All my projects have root namespaces.
If I understand things correctly the difference between C# and VB in this respect is....
...In C# this value is copied into each source file as each is created.
...In VB.Net this value is used at compile-time (and background compile-time) and every class in the system is wrapped in said namespace.
This means that a large VB.Net program is very sensitive to any changes to this particular value.
If I keep my default namespaces, then I cannot create this attribute in this namespace. I had thought I could declare the Attribute using "Namespace Global.System.Runtime.CompilerServices" but the keyword cannot be used in this way.
It looks like I will have to create a brand new project, to create a brand new dll, just so that I can put a single attribute in it.
It seems that this is another Compiler/Language deficiency for which the only answer is to create another assembly.
Perhaps I will call my new dll "System.Core.Dll" :D