. "pointers of value NULL" . "Null pointer" . "Null pointers" . "Null_pointer#Null_dereferencing" . . . "null" . "Null pointer#Dereferencing" . "nil" . "null dereferences" . . . . . "NULL" . . "Null pointer#History" . "billion-dollar mistake" . "NullPointerException" . "Nulls" . "null pointer" . "Null pointer" . . "Dereferencing" . "null value" . "Nil" . "Null_pointer" . "Null pointer dereferencing" . . "null reference" . "Null reference" . "pointer" . . "Null values" . "Null" . . . "''null'' or ''void''" . "Null pointer#Null dereferencing" . "0" . "accidental dereferencing" . "null pointer dereferencing" .