1. A method, implemented at least in part by a computing device comprising a processing unit and memory, of representing type information for a typed intermediate language via objects of classes in a class hierarchy, wherein the class hierarchy comprises at least one class and a plurality of sub-classes for representing different type classifications, the method comprising: with the computing device: instantiating one or more objects of one or more of the sub-classes of the hierarchy, wherein the one or more sub-classes represent classifications of types for the typed intermediate language; and storing information in the one or more objects; wherein the typed intermediate language is capable of representing a plurality of different programming languages, and wherein the one or more objects represent type information for instructions in the typed intermediate language; wherein the classifications of types comprises a primitive type associated with a primitive type size, and wherein the primitive type size is settable to represent a constant size, the primitive type size is settable to represent a symbolic size, and the primitive type size is settable to represent an unknown size; and wherein one of the sub-classes representing a primitive type represents an unknown type, wherein the unknown type can represent any type, wherein the unknown type represents a lack of all type information, wherein a compiler drops type information by changing a known type to the unknown type during a stage of lowering, wherein the unknown type is set independently of the primitive type size, and wherein the classifications of types support an unknown type with an unknown primitive type size.