Uninitialized scalar field

The field will contain an arbitrary value left over from earlier computations. A scalar field is not initialized by the constructor
/src/mongo/db/exec/sbe/stages/spool.h:245: UNINIT_CTOR 115718 Class member declaration for "_bufferIt".
/src/mongo/db/exec/sbe/stages/spool.h:150: UNINIT_CTOR 115718 Non-static class member "_bufferIt" is not initialized in this constructor nor in any functions that it calls.