xen/x86: Add -Wnested-externs to CFLAGS

This will catch any new extern declarations that happen actually
inside function bodies.  Unfortunately there's no equivalent
warning for extern declarations at rootl level in .c files.

Signed-off-by: Tim Deegan <Tim.Deegan@citrix.com>

diff --git a/xen/arch/x86/Rules.mk b/xen/arch/x86/Rules.mk
index c15df0281ec830e64441fb52bf79ea571dc553e7..bf77aef8b20d2423509a63d0a1d95e36b91c8b91 100644 (file)
--- a/xen/arch/x86/Rules.mk
+++ b/xen/arch/x86/Rules.mk
@@ -27,6 +27,7 @@ CFLAGS += -I$(BASEDIR)/include/asm-x86/mach-default
 CFLAGS += -msoft-float
 
 $(call cc-options-add,CFLAGS,CC,$(EMBEDDED_EXTRA_CFLAGS))
+$(call cc-option-add,CFLAGS,CC,-Wnested-externs)
 
 ifeq ($(supervisor_mode_kernel),y)
 CFLAGS += -DCONFIG_X86_SUPERVISOR_MODE_KERNEL=1