TAGDIFFER

Message        <Context> the tag "<name>" differs from the tag
               "<name>" used in an earlier declaration of this
               function.

Description    This function declaration contains a parameter that
               is a pointer to a struct or union type whose tag
               differs from the tag of the struct or union type
               referenced by a pointer type in an earlier
               declaration of this function.  In most modes of the
               compiler, this will cause the function declarations
               to be incompatible.

User Action    Multiple declarations of a function should use
               exactly the same parameter types.