diff --git a/Makefile b/Makefile
index 67ee007..9d449b0 100644
--- a/Makefile
+++ b/Makefile
@@ -47,7 +47,7 @@ LFLAGS += -mfloat-abi=soft --disable-newlib-supplied-syscalls -nostartfiles
 LFLAGS += -Tstartup/stm32f030.ld -Wl,-Map=$(mapfile).map -Wl,--gc-sections -Wl,--print-memory-usage -g
 
 CFLAGS = -c -fmessage-length=0 -mlittle-endian -mthumb -mcpu=cortex-m0
-CFLAGS += -mfloat-abi=soft -nostartfiles -Wall -g3 -O0
+CFLAGS += -mfloat-abi=soft -nostartfiles -Wall -Wextra -g3 -O0
 
 ####################################################################################
 
diff --git a/main.c b/main.c
index 1fda20c..7b62b33 100644
--- a/main.c
+++ b/main.c
@@ -107,7 +107,7 @@ static void set_angle(uint32_t led_count, uint32_t pos, uint32_t width, const st
 	}
 
 	/* Set the rest ring to rest color */
-	for (idx = upper_end + 1; idx < (upper_end + 1 + (led_count - width)); idx++) {
+	for (idx = upper_end + 1; idx < (upper_end + 1 + (int32_t)(led_count - width)); idx++) {
 		mapped_idx = map_index_to_range(idx, led_count);
 		dmx_universe_set_rgbw(mapped_idx, rest);
 	}
@@ -234,7 +234,7 @@ static bool mode_is_continuous(enum color_mode mode)
 
 int main(void)
 {
-	int i;
+	unsigned int i;
 	uint8_t port;
 	uint8_t button_pressed;
 	enum color_mode mode = MODE_DMX_SHUTDOWN;