Fixed division by zero check

phases/constprop.ml

@@ -56,7 +56,7 @@ let eval = function
   | Binop (Mul, Const (FloatVal left, _), Const (FloatVal right, _), ann) ->
     Const (FloatVal (left *. right), ann)
 
-  | Binop (Div, Const (IntVal left, _), Const (IntVal right, _), ann) when right != 0l ->
+  | Binop (Div, Const (IntVal left, _), Const (IntVal right, _), ann) when right <> 0l ->
     Const (IntVal (left / right), ann)
   | Binop (Div, Const (FloatVal left, _), Const (FloatVal right, _), ann) ->
     Const (FloatVal (left /. right), ann)