In recent work we have proposed a novel approach to define idealized
type systems for object-oriented languages, based on abstract compilation of
programs into Horn formulas which are interpreted w.r.t. the coinductive (that is, the greatest) Herbrand model. In this paper we investigate how this approach can be applied also in
the presence of imperative features.
This is made possible by considering a natural translation of Static Single Assignment intermediate form programs into Horn formulas, where φ functions
correspond to union types.