Unused value

An assigned value that is never used may represent unnecessary computation, an incorrect algorithm, or possibly the need for cleanup or refactoring. A value assigned to a variable is never used.
/src/mongo/db/storage/key_string.cpp:2439: UNUSED_VALUE 114418 Overwriting previous write to "ctype" with value from "mongo::KeyString::<unnamed>::readType(&reader, false)".
/src/mongo/db/storage/key_string.cpp:2438: UNUSED_VALUE 114418 Assigning value from "~ctype" to "ctype" here, but that stored value is overwritten before it can be used.