Index: libc/Makefile.toolchain
===================================================================
--- libc/Makefile.toolchain	(revision a3d2939a62181127d9643ff191dfc085474b2bfa)
+++ libc/Makefile.toolchain	(revision e0bfcf8c8e31a86e65b0d0d941f449305cd44849)
@@ -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 -O3 -nostdlib -nostdinc -I$(LIBC_PREFIX)/include
 LFLAGS = -M -N $(SOFTINT_PREFIX)/libsoftint.a
 AFLAGS =