openvaf crash with $limit(V(a,b))

[gjcoram]

If you don't specify a limiting function (either a "string" for a built-in or an analog function identifier), then openvaf will crash when compiling the module.
The problem is this line in openvaf/hir_ty/src/inference.rs:
infere_args = &args[0..2];
and then later:
if let Some(Ty::UserFunction(func)) = self.result.expr_types.get(args[1]).cloned() {