not a valid display filter

In 1.8.5, One of my protocol "wimax-btsbts" is not getting registered. If I try to apply filter 'wimax-btsbts', wireshark pop-ups a notification saying Wiax-btsbts is not a valid display filter. I have removed the below last lines :

#ifndef ENABLE_STATIC

G_MODULE_EXPORT void

plugin_register(void)

{

/*register the new protocol, protocol fields, and subtrees */
if (proto_btsBts == -1) { /* execute protocol initialization only once */
    proto_register_BTS_BTS();
}

}

G_MODULE_EXPORT void

plugin_reg_handoff(void){
    proto_reg_handoff_bts_bts();

}

#endif

If I include above compile-time error fatal error LNK1169: one or more multiply defined symbols found occurs. It seems that proto_register never get hit during compilation.Where could be the probable issue?