[Android Q&A, Help & Troubleshooting] antonio8297:
now have this

external/bluetooth/bluedroid/hci/src/bt_hci_bdroid.c: In function 'preload':
external/bluetooth/bluedroid/hci/src/bt_hci_bdroid.c:301:29: warning: unused parameter 'transac' [-Wunused-parameter]
static void preload(TRANSAC transac)
^
external/bluetooth/bluedroid/hci/src/bt_hci_bdroid.c: In function 'postload':
external/bluetooth/bluedroid/hci/src/bt_hci_bdroid.c:309:30: warning: unused parameter 'transac' [-Wunused-parameter]
static void postload(TRANSAC transac)
^
external/bluetooth/bluedroid/hci/src/bt_hci_bdroid.c: In function 'transmit_buf':
external/bluetooth/bluedroid/hci/src/bt_hci_bdroid.c:317:48: warning: unused parameter 'p_buf' [-Wunused-parameter]
static int transmit_buf(TRANSAC transac, char *p_buf, int len)
^
external/bluetooth/bluedroid/hci/src/bt_hci_bdroid.c:317:59: warning: unused parameter 'len' [-Wunused-parameter]
static int transmit_buf(TRANSAC transac, char *p_buf, int len)
^
external/bluetooth/bluedroid/hci/src/bt_hci_bdroid.c: In function 'bt_hc_worker_thread':
external/bluetooth/bluedroid/hci/src/bt_hci_bdroid.c:506:52: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
while (p_next_msg && sending_msg_count <
^
external/bluetooth/bluedroid/hci/src/bt_hci_bdroid.c:424:40: warning: unused parameter 'arg' [-Wunused-parameter]
static void *bt_hc_worker_thread(void *arg)
^
external/bluetooth/bluedroid/hci/src/lpm.c: In function 'lpm_idle_timeout':
external/bluetooth/bluedroid/hci/src/lpm.c:110:43: warning: unused parameter 'arg' [-Wunused-parameter]
static void lpm_idle_timeout(union sigval arg)
^
target thumb C: libbt-hci <= external/bluetooth/bluedroid/hci/src/bt_hw.c
external/bluetooth/bluedroid/hci/src/bt_hw.c: In function 'scocfg_cb':
external/bluetooth/bluedroid/hci/src/bt_hw.c:88:45: warning: unused parameter 'result' [-Wunused-parameter]
static void scocfg_cb(bt_vendor_op_result_t result)
^
external/bluetooth/bluedroid/hci/src/bt_hw.c: In function 'epilog_cb':
external/bluetooth/bluedroid/hci/src/bt_hw.c:179:45: warning: unused parameter 'result' [-Wunused-parameter]
static void epilog_cb(bt_vendor_op_result_t result)
^
target thumb C: libbt-hci <= external/bluetooth/bluedroid/hci/src/btsnoop.c
target thumb C: libbt-hci <= external/bluetooth/bluedroid/hci/src/utils.c
external/bluetooth/bluedroid/hci/src/btsnoop.c: In function 'interruptFn':
external/bluetooth/bluedroid/hci/src/btsnoop.c:543:30: warning: unused parameter 'sig' [-Wunused-parameter]
static void interruptFn (int sig)
^
external/bluetooth/bluedroid/hci/src/btsnoop.c: In function 'ext_parser_thread':
external/bluetooth/bluedroid/hci/src/btsnoop.c:549:37: warning: unused parameter 'param' [-Wunused-parameter]
static void ext_parser_thread(void* param)
^
target thumb C: libbt-hci <= external/bluetooth/bluedroid/hci/src/hci_h4.c
target thumb C: libbt-hci <= external/bluetooth/bluedroid/hci/src/userial.c
external/bluetooth/bluedroid/hci/src/userial.c: In function 'userial_read_thread':
external/bluetooth/bluedroid/hci/src/userial.c:239:40: warning: unused parameter 'arg' [-Wunused-parameter]
static void *userial_read_thread(void *arg)
^
external/bluetooth/bluedroid/hci/src/userial.c: In function 'userial_read':
external/bluetooth/bluedroid/hci/src/userial.c:428:33: warning: unused parameter 'msg_id' [-Wunused-parameter]
uint16_t userial_read(uint16_t msg_id, uint8_t *p_buffer, uint16_t len)
^
external/bluetooth/bluedroid/hci/src/userial.c: In function 'userial_write':
external/bluetooth/bluedroid/hci/src/userial.c:482:33: warning: unused parameter 'msg_id' [-Wunused-parameter]
uint16_t userial_write(uint16_t msg_id, uint8_t *p_data, uint16_t len)
^
external/bluetooth/bluedroid/hci/src/userial.c: In function 'userial_ioctl':
external/bluetooth/bluedroid/hci/src/userial.c:545:49: warning: unused parameter 'p_data' [-Wunused-parameter]
void userial_ioctl(userial_ioctl_op_t op, void *p_data)
^
target thumb C: libbt-utils <= external/bluetooth/bluedroid/utils/./src/bt_utils.c
target thumb C: libbt-brcm_gki <= external/bluetooth/bluedroid/gki/./ulinux/gki_ulinux.c
target thumb C: libbt-brcm_gki <= external/bluetooth/bluedroid/gki/./common/gki_debug.c
target thumb C: libbt-brcm_gki <= external/bluetooth/bluedroid/gki/./common/gki_time.c
target thumb C: libbt-brcm_gki <= external/bluetooth/bluedroid/gki/./common/gki_buffer.c
external/bluetooth/bluedroid/gki/./ulinux/gki_ulinux.c: In function 'GKI_create_task':
external/bluetooth/bluedroid/gki/./ulinux/gki_ulinux.c:243:83: error: unused parameter 'stack' [-Werror=unused-parameter]
UINT8 GKI_create_task (TASKPTR task_entry, UINT8 task_id, INT8 *taskname, UINT16 *stack, UINT16 stacksize)
^
external/bluetooth/bluedroid/gki/./ulinux/gki_ulinux.c:243:97: error: unused parameter 'stacksize' [-Werror=unused-parameter]
UINT8 GKI_create_task (TASKPTR task_entry, UINT8 task_id, INT8 *taskname, UINT16 *stack, UINT16 stacksize)
^
external/bluetooth/bluedroid/gki/./ulinux/gki_ulinux.c: In function 'timer_thread':
external/bluetooth/bluedroid/gki/./ulinux/gki_ulinux.c:607:26: error: unused parameter 'arg' [-Werror=unused-parameter]
void* timer_thread(void *arg)
^
external/bluetooth/bluedroid/gki/./ulinux/gki_ulinux.c: In function 'GKI_run':
external/bluetooth/bluedroid/gki/./ulinux/gki_ulinux.c:784:21: error: unused parameter 'p_task_id' [-Werror=unused-parameter]
void GKI_run (void *p_task_id)
^
external/bluetooth/bluedroid/gki/./ulinux/gki_ulinux.c: In function 'GKI_suspend_task':
external/bluetooth/bluedroid/gki/./ulinux/gki_ulinux.c:1403:31: error: unused parameter 'task_id' [-Werror=unused-parameter]
UINT8 GKI_suspend_task (UINT8 task_id)
^
external/bluetooth/bluedroid/gki/./ulinux/gki_ulinux.c: In function 'GKI_resume_task':
external/bluetooth/bluedroid/gki/./ulinux/gki_ulinux.c:1429:30: error: unused parameter 'task_id' [-Werror=unused-parameter]
UINT8 GKI_resume_task (UINT8 task_id)
^
cc1: all warnings being treated as errors
make: *** [out/target/product/maguro/obj/STATIC_LIBRARIES/libbt-brcm_gki_intermediates/./ulinux/gki_ulinux.o] Errore 1
make: *** Attesa per i processi non terminati....

edit:Fixed!