Dereference before null check

There may be a null pointer dereference, or else the comparison against null is unnecessary. All paths that lead to this null pointer comparison already dereference the pointer earlier
/src/mongo/db/curop.cpp:1088: REVERSE_INULL 116702 Null-checking "client" suggests that it may be null, but it has already been dereferenced on all paths leading to the check.