Two modules that include LDAP.H can be compiled with different
    pointer sizes and linked together. While each module may use the
    LDAP API on its own, it may not be possible for both modules to
    share LDAP-related data.

    None of the public LDAP data structures is directly compatible
    between 32- and 64-bit modules. For example, a BerValue that
    has been allocated by a 32-bit module does not have the same
    layout as a BerValue which a 64-bit module expects to see, and
    consequently cannot be exchanged between two such modules without
    some sort of data conversion taking place.

    Opaque data structures (such as LDAP *) have only a single
    structure definition inside the library, and so pointers to such
    structures may be exchanged between 32- and 64-bit callers. Note
    that these structures are allocated only by the library itself,
    and, in the case of a 64-bit caller, these structures may be
    allocated in 64-bit space. So while the LDAP handle returned to
    a 32-bit caller of ldap_init() could safely be used by a 64-bit
    module, the reverse may not be true.