compile with -Wextra

firmware/CMakeLists.txt

 
 target_compile_options(trackball PUBLIC
     -Wall
+    -Wextra
     -Werror
 )
 

firmware/src/console.c

 }
 
 static int32_t cnsl_find_line_end(void) {
-    for (int32_t i = 0; i < cnsl_buff_pos; i++) {
+    for (uint32_t i = 0; i < cnsl_buff_pos; i++) {
         if ((cnsl_line_buff[i] == '\r') || (cnsl_line_buff[i] == '\n')) {
             return i;
         }

firmware/src/debug.c

     } else {
         UINT bw;
         res = f_write(&file, frame, r, &bw);
-        if ((res != FR_OK) || (bw != r)) {
+        if ((res != FR_OK) || ((ssize_t)bw != r)) {
             debug("error: f_write returned %d", res);
         }
     }

firmware/src/log.c

 
     char buff[32];
     int l = snprintf(buff, sizeof(buff), "\r\n\r\nbuffered log output:\r\n");
-    if ((l > 0) && (l <= sizeof(buff))) {
+    if ((l > 0) && (l <= (int)sizeof(buff))) {
         usb_cdc_write(buff, l);
     }
 
     }
 
     l = snprintf(buff, sizeof(buff), "\r\n\r\nlive log:\r\n");
-    if ((l > 0) && (l <= sizeof(buff))) {
+    if ((l > 0) && (l <= (int)sizeof(buff))) {
         usb_cdc_write(buff, l);
     }
 }
     if (l < 0) {
         // encoding error
         l = snprintf(buff, len, "%s: encoding error\r\n", __func__);
-    } else if (l >= len) {
+    } else if (l >= (ssize_t)len) {
         // not enough space for string
         l = snprintf(buff, len, "%s: message too long (%d)\r\n", __func__, l);
     }
     int l = format_debug_log(line_buff, sizeof(line_buff), format, args);
     va_end(args);
 
-    if ((l > 0) && (l <= sizeof(line_buff))) {
+    if ((l > 0) && (l <= (int)sizeof(line_buff))) {
         usb_cdc_write(line_buff, l);
 
         if (log) {