diff --git a/lib/libusbx52/usb_x52_stub.c b/lib/libusbx52/usb_x52_stub.c
index 9209539..4992485 100644
--- a/lib/libusbx52/usb_x52_stub.c
+++ b/lib/libusbx52/usb_x52_stub.c
@@ -16,8 +16,8 @@ int libusb_init(libusb_context **ctx)
 {
     int rc;
     int dev_count;
-    int vid;
-    int pid;
+    unsigned int vid;
+    unsigned int pid;
     int parsed;
     char *dev_list_file;
     FILE *dev_list;
@@ -180,9 +180,8 @@ ssize_t libusb_get_device_list(libusb_context *ctx, libusb_device ***list)
 
 void libusb_free_device_list(libusb_device **list, int unref_devices)
 {
-    libusb_device **dev;
-
     if (unref_devices) {
+        libusb_device **dev;
         for (dev = list; *dev; dev++) {
             /* Decrement the refcount */
             (*dev)->ref_count -= 1;
@@ -277,14 +276,13 @@ int libusb_control_transfer(libusb_device_handle *dev_handle,
                             uint16_t wLength,
                             unsigned int timeout)
 {
-    int i;
-
     /* Always log the control transfer */
     fprintf(dev_handle->packet_data_file,
         "%s: RqType: %02x bRequest: %02x wValue: %04x wIndex: %04x timeout: %d\n",
         __func__, request_type, bRequest, wValue, wIndex, timeout);
     if (data != NULL) {
-        fprintf(dev_handle->packet_data_file, "%s: Data[%d]: ", __func__,
+        int i;
+        fprintf(dev_handle->packet_data_file, "%s: Data[%u]: ", __func__,
                 wLength);
         for (i = 0; i < wLength; i++) {
             fprintf(dev_handle->packet_data_file, "%02x ", data[i]);
diff --git a/lib/libusbx52/util/create_device_list.c b/lib/libusbx52/util/create_device_list.c
index 8ccb9b1..d724146 100644
--- a/lib/libusbx52/util/create_device_list.c
+++ b/lib/libusbx52/util/create_device_list.c
@@ -19,9 +19,8 @@ int main(int argc, char *argv[])
     char *data_file;
     FILE *data;
     char **id_pair;
-    int vid;
-    int pid;
-    int parsed;
+    unsigned int vid;
+    unsigned int pid;
     int i;
 
     data_file = getenv(INPUT_DEVICE_LIST_ENV);
@@ -36,6 +35,7 @@ int main(int argc, char *argv[])
 
     /* Process arguments until there are fewer than 2 remaining */
     for (i = 1; i < argc && (argc - i) >= 2; i += 2) {
+        int parsed;
         parsed = sscanf(argv[i], "%x", &vid);
         if (parsed != 1) break;
 
diff --git a/lib/libusbx52/util/log_actions.c b/lib/libusbx52/util/log_actions.c
index a350d0d..70a0a7d 100644
--- a/lib/libusbx52/util/log_actions.c
+++ b/lib/libusbx52/util/log_actions.c
@@ -32,7 +32,6 @@ static libusb_device_handle *libusbx52_init(void)
     ssize_t count;
     int i;
     libusb_device **list;
-    libusb_device *device;
     libusb_device_handle *hdl = NULL;
     struct libusb_device_descriptor desc;
 
@@ -54,7 +53,7 @@ static libusb_device_handle *libusbx52_init(void)
 
     count = libusb_get_device_list(global_context, &list);
     for (i = 0; i < count; i++) {
-        device = list[i];
+        libusb_device *device = list[i];
         if (!libusb_get_device_descriptor(device, &desc)) {
             if (desc.idVendor == 0x06a3) {
                 if (desc.idProduct == 0x0762) {
@@ -76,9 +75,8 @@ static libusb_device_handle *libusbx52_init(void)
 
 int main(int argc, char *argv[])
 {
-    int index;
-    int value;
-    int parsed;
+    unsigned int index;
+    unsigned int value;
     int i;
     libusb_device_handle *hdl;
     libusb_context *ctx;
@@ -88,6 +86,7 @@ int main(int argc, char *argv[])
 
     /* Process arguments until there are fewer than 2 remaining */
     for (i = 1; i < argc && (argc - i) >= 2; i += 2) {
+        int parsed;
         parsed = sscanf(argv[i], "%x", &index);
         if (parsed != 1) break;