Dereference after null check

Either the check against null is unnecessary, or there may be a null pointer dereference. Pointer is checked against null but then dereferenced anyway
/src/mongo/db/catalog/create_collection.cpp:525: FORWARD_NULL 117786 Comparing "db" to null implies that "db" might be null.
/src/mongo/db/catalog/create_collection.cpp:532: FORWARD_NULL 117786 Passing null pointer "db" to "makeUniqueCollectionNamespace", which dereferences it. (The dereference happens because this is a virtual function call.)