enable -fwrapv globally

mk/vars.mk

@@ -14,7 +14,7 @@ TARGET_DEBUGGING:=	-g3 -fno-omit-frame-pointer
 else
 TARGET_DEBUGGING:=	-fomit-frame-pointer $(TARGET_OPTIMIZATION) 
 endif
-TARGET_CFLAGS:=		$(TARGET_CFLAGS_ARCH) $(TARGET_DEBUGGING)
+TARGET_CFLAGS:=		$(TARGET_CFLAGS_ARCH) $(TARGET_DEBUGGING) -fwrapv
 ifneq ($(ADK_TARGET_ARCH_OPTIMIZATION),)
 TARGET_CFLAGS+=		-march=$(ADK_TARGET_ARCH_OPTIMIZATION)
 endif