Code block is unreachable because of the syntactic structure of the code

Defect 100005 (STATIC_C)
Checker UNREACHABLE (subcategory none)
File: /src/mongoc/mongoc-handshake.c
Function _get_os_type
/src/mongoc/mongoc-handshake.c, line: 121
This code cannot be reached: "return bson_strndup("unknow...".

       return bson_strndup ("unknown", HANDSHAKE_OS_TYPE_MAX);