Avoid default constructing code_ifthenelset

The default constructor is deprecated.

Author: tautschnig

jbmc/src/java_bytecode/java_bytecode_instrument.cpp

@@ -229,14 +229,15 @@ code_ifthenelset java_bytecode_instrumentt::check_class_cast(
   if(null_check_op.type()!=voidptr)
     null_check_op.make_typecast(voidptr);
 
-  codet check_code;
   if(throw_runtime_exceptions)
   {
-    check_code=
+    return code_ifthenelset(
+      notequal_exprt(
+        std::move(null_check_op), null_pointer_exprt(std::move(voidptr))),
       throw_exception(
         not_exprt(class_cast_check),
         original_loc,
-        "java.lang.ClassCastException");
+        "java.lang.ClassCastException"));
   }
   else
   {
@@ -246,12 +247,11 @@ code_ifthenelset java_bytecode_instrumentt::check_class_cast(
 
     codet assert_class = create_fatal_assertion(class_cast_check, check_loc);
 
-    check_code=std::move(assert_class);
+    return code_ifthenelset(
+      notequal_exprt(
+        std::move(null_check_op), null_pointer_exprt(std::move(voidptr))),
+      std::move(assert_class));
   }
-
-  return code_ifthenelset(
-    notequal_exprt(std::move(null_check_op), null_pointer_exprt(voidptr)),
-    std::move(check_code));
 }
 
 /// Checks whether \p expr is null and throws NullPointerException/