for Base+16>, a = 0, b = 0}
(gdb) info vtbl b
vtable for 'Base' @ 0x400a90 (subobject @ 0x7fffffffe2e0...(gdb) p d
$2 = { = {_vptr.Base = 0x400a50 , a = 0, b = 0}, c = 1}
(gdb) info...vtbl d
vtable for 'Derive' @ 0x400a50 (subobject @ 0x7fffffffe2c0):
[0]: 0x40086e <Derive::function(...(gdb) p *d2
$5 = { = { = {_vptr.Base = 0x4009d0 , a = 0,...b = 0}, c = 0},
= {_vptr.Test = 0x400a00 , vv = 0}, d2 = 0}
(