Why SOS Debugging Extension can NOT debug Nullable type?

Question

static void Main( string [] args) { Nullable int > nullINT = 100; } 1).load sos.dll 2)!clrstack -l Cannot trace out the variable info. But for this following code static void Main( string [] args) { SimpleClass sc1 = new SimpleClass (); } 1).load sos.dll 2)!clrstack -l Can trace out the variable info right now. Looks like this LOCALS: 0x0012f420 = 0x0130652c 0x0012f41c = 0x00000000 0x0012f40c = 0x00000000 Why SOS Debugging Extension can NOT debug Nullable type?

Vulpes · Answer

There does seem to be something odd about debugging System.Nullable which is the only generic struct I can think of in the .NET Framework. Check this blog ( http://naveensrinivasan.com/category/windbg/sos-windbg/ ) and the section headed 'Debugging Generic System.Nullable within Windbg' which may throw some light on the matter.