readType reads a type from r at off of name. It adds types to the type cache, appends new typedef types to typedefs, and computes the sizes of types. Callers should pass nil for typedefs; this is used for internal recursion.
(name string, r typeReader, off Offset, typeCache map[Offset]Type, typedefs *[]*TypedefType)
source not stored for this graph (policy: none)