I encounter the similar problem.

I found the reason is the driver struct list is defined in miner.h which is included by many c files.

So, I resolve this problem by two steps:

1. mask the following line in miner.h

   /* Use DRIVER_PARSE_COMMANDS to generate extern device_drv prototypes*/

   //DRIVER_PARSE_COMMANDS(DRIVER_PROTOTYPE)

2. add the masked line in the beginning of cgminer.c, after miner.h is included

   DRIVER_PARSE_COMMANDS(DRIVER_PROTOTYPE)

It's done.