StructDomain.Sinclude Lattice.Sinclude Lattice.POwiden x y assumes leq x y. Solvers guarantee this by calling widen old (join old new).
val invariant :
value_invariant:
(offset:GoblintCil.Cil.offset ->
lval:GoblintCil.Cil.lval ->
value ->
Invariant.t) ->
offset:GoblintCil.Cil.offset ->
lval:GoblintCil.Cil.lval ->
t ->
Invariant.t