Remove deprecated is_null_pointer

This was deprecated over 6 months ago.

Author: tautschnig

src/util/expr.cpp

@@ -80,7 +80,7 @@ bool exprt::is_zero() const
     }
     else if(type_id==ID_pointer)
     {
-      return is_null_pointer(constant);
+      return constant.is_null_pointer();
     }
   }
 

src/util/expr_util.cpp

@@ -340,8 +340,3 @@ exprt make_and(exprt a, exprt b)
   }
   return and_exprt{std::move(a), std::move(b)};
 }
-
-bool is_null_pointer(const constant_exprt &expr)
-{
-  return expr.is_null_pointer();
-}

src/util/expr_util.h

@@ -115,10 +115,4 @@ constant_exprt make_boolean_expr(bool);
 /// return the other expression. If one is `false` returns `false`.
 exprt make_and(exprt a, exprt b);
 
-/// Returns true if \p expr has a pointer type and a value NULL; it also returns
-/// true when \p expr has value zero and NULL_is_zero is true; returns false in
-/// all other cases.
-DEPRECATED(SINCE(2024, 9, 10, "use constant_exprt::is_null_pointer() instead"))
-bool is_null_pointer(const constant_exprt &expr);
-
 #endif // CPROVER_UTIL_EXPR_UTIL_H