diff --git a/apps/bttester/src/gatt.c b/apps/bttester/src/gatt.c
index d40de262b..2a8545b36 100644
--- a/apps/bttester/src/gatt.c
+++ b/apps/bttester/src/gatt.c
@@ -654,7 +654,7 @@ static void discover_destroy(void)
 	gatt_buf_clear();
 }
 
-static void read_destroy()
+static void read_destroy(void)
 {
 	gatt_buf_clear();
 }
diff --git a/nimble/host/store/config/src/ble_store_nvs.c b/nimble/host/store/config/src/ble_store_nvs.c
index c19c0be89..98a78ff85 100644
--- a/nimble/host/store/config/src/ble_store_nvs.c
+++ b/nimble/host/store/config/src/ble_store_nvs.c
@@ -329,7 +329,7 @@ populate_db_from_nvs(int obj_type, void *dst, int *db_num)
  * the keys in database may get lost.
  */
 static int
-ble_nvs_restore_sec_keys()
+ble_nvs_restore_sec_keys(void)
 {
     esp_err_t err;
 
@@ -362,7 +362,7 @@ ble_nvs_restore_sec_keys()
     return 0;
 }
 
-int ble_store_config_persist_cccds()
+int ble_store_config_persist_cccds(void)
 {
     int nvs_count, nvs_idx;
     union ble_store_value val;
@@ -388,7 +388,7 @@ int ble_store_config_persist_cccds()
     return 0;
 }
 
-int ble_store_config_persist_peer_secs()
+int ble_store_config_persist_peer_secs(void)
 {
     int nvs_count, nvs_idx;
     union ble_store_value val;
@@ -414,7 +414,7 @@ int ble_store_config_persist_peer_secs()
     return 0;
 }
 
-int ble_store_config_persist_our_secs()
+int ble_store_config_persist_our_secs(void)
 {
     int nvs_count, nvs_idx;
     union ble_store_value val;
@@ -440,7 +440,7 @@ int ble_store_config_persist_our_secs()
     return 0;
 }
 
-void ble_store_config_conf_init()
+void ble_store_config_conf_init(void)
 {
     esp_err_t err;