Index: libc/Makefile.toolchain
===================================================================
--- libc/Makefile.toolchain	(revision 8bd0316b545b2aca32be2e65dba40e58845a524e)
+++ libc/Makefile.toolchain	(revision a46da63bc614b7dbb15e300eaea5cfd47fe15b63)
@@ -28,5 +28,5 @@
 
 DEFS = -DARCH=$(ARCH)
-CFLAGS = -fno-builtin -Werror-implicit-function-declaration -Wmissing-prototypes  -O3 -nostdlib -nostdinc -I$(LIBC_PREFIX)/include
+CFLAGS = -fno-builtin -Wall -Werror-implicit-function-declaration -Wmissing-prototypes -Werror -O3 -nostdlib -nostdinc -I$(LIBC_PREFIX)/include
 LFLAGS = -M -N $(SOFTINT_PREFIX)/libsoftint.a
 AFLAGS =