Pointer to local outside scope

Dereferencing the returned or out-of-scope stack pointer will access an invalid location on the stack after its scope or after the function returns. Pointer to a local stack variable returned or used outside scope
/src/mongo/db/query/planner_analysis.cpp:634: RETURN_LOCAL 121548 Assigning: "prefixedIndex" = "&idxEntry" (address of local variable "idxEntry").
/src/mongo/db/query/planner_analysis.cpp:635: RETURN_LOCAL 121548 Variable "idxEntry" goes out of scope.
/src/mongo/db/query/planner_analysis.cpp:643: RETURN_LOCAL 121548 Using "prefixedIndex", which points to an out-of-scope variable "idxEntry".