diff --git a/sys/uart_stdio/Makefile b/sys/uart_stdio/Makefile
index 48422e909a47d7cd428d10fa73825060ccc8d8c2..7f3b72f4a69c5b01dcc912c1764de17ee122ae99 100644
--- a/sys/uart_stdio/Makefile
+++ b/sys/uart_stdio/Makefile
@@ -1 +1,4 @@
+ifeq (gnu, $(TOOLCHAIN))
+  CFLAGS += -Wno-cast-function-type
+endif
 include $(RIOTBASE)/Makefile.base