Incorrect sizeof expression

This is usually caused by a typo or a misunderstanding of the sizeof operator, which should be applied to the actual type whose size is desired. An incorrect sizeof value is used in further computation. The sizeof operator was applied to an unintended variable or expression, such as a pointer variable instead of its target
/src/mongo/db/index/sort_key_generator.h:102: BAD_SIZEOF 135418 Taking the size of "this" is suspicious.