Hi,

While working on some (more) symbol table bugs, I noticed that 
derivation.exp doesn't test the ptype of the variable g_instance. I 
presume this is because cp_test_ptype_class doesn't support typedefs.

Since it is pretty easy to do, and I will need it for a follow-on patch, 
I'm submitting this omission now, adding the missing tests and support.

Ok?
Keith

testsuite/ChangeLog
2012-10-03  Keith Seitz  <keiths@redhat.com>

	* lib/cp-support.exp (cp_test_ptype_class): Add support
	for class typedefs.
	* gdb.cp/derivation.exp: Add tests for g_instance.