diff --git a/Makefile b/Makefile
index ff8408b..897f5cb 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 
 TEST_OBJS = $(addsuffix .o,$(basename $(wildcard tests/*.S)))
 FIRMWARE_OBJS = firmware/start.o firmware/irq.o firmware/print.o firmware/sieve.o firmware/multest.o firmware/stats.o
-GCC_WARNS  = -Wall -Wextra -Wshadow -Wundef -Wpointer-arith -Wcast-qual -Wcast-align -Wwrite-strings
+GCC_WARNS  = -Werror -Wall -Wextra -Wshadow -Wundef -Wpointer-arith -Wcast-qual -Wcast-align -Wwrite-strings
 GCC_WARNS += -Wredundant-decls -Wstrict-prototypes -Wmissing-prototypes -pedantic # -Wconversion
 TOOLCHAIN_PREFIX = riscv64-unknown-elf-