public void AddVirtualReferences(Collection<AssemblyNameReference> references)
{
var corlib = GetCoreLibrary (references);
corlib_version = corlib.Version;
corlib.Version = version;
if (virtual_references == null) {
var winrt_references = GetAssemblyReferences (corlib);
Interlocked.CompareExchange (ref virtual_references, winrt_references, null);
}
foreach (var reference in virtual_references)
references.Add (reference);
}