And thus avoiding checking for those variable over and over again.

Also, add "e.g." in the error messages to hint that "menuconfig"
isn't the only way.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
---

Notes:
    v7:
    - Add "e.g." into the error message to hint that menuconfig isn't the
      only way.

 xen/Makefile | 22 ++++++++++++++++++++++
 xen/Rules.mk | 22 ----------------------
 2 files changed, 22 insertions(+), 22 deletions(-)

diff --git a/xen/Makefile b/xen/Makefile
index f35a4d84f7cd..2c56546cd1dc 100644
--- a/xen/Makefile
+++ b/xen/Makefile
@@ -56,6 +56,28 @@ include scripts/Kbuild.include
 ifneq ($(root-make-done),y)
 # section to run before calling Rules.mk, but only once.
 
+ifneq ($(origin crash_debug),undefined)
+$(error "You must use e.g. 'make menuconfig' to enable/disable crash_debug now.")
+endif
+ifeq ($(origin debug),command line)
+$(warning "You must use e.g. 'make menuconfig' to enable/disable debug now.")
+endif
+ifneq ($(origin frame_pointer),undefined)
+$(error "You must use e.g. 'make menuconfig' to enable/disable frame_pointer now.")
+endif
+ifneq ($(origin kexec),undefined)
+$(error "You must use e.g. 'make menuconfig' to enable/disable kexec now.")
+endif
+ifneq ($(origin lock_profile),undefined)
+$(error "You must use e.g. 'make menuconfig' to enable/disable lock_profile now.")
+endif
+ifneq ($(origin perfc),undefined)
+$(error "You must use e.g. 'make menuconfig' to enable/disable perfc now.")
+endif
+ifneq ($(origin verbose),undefined)
+$(error "You must use e.g. 'make menuconfig' to enable/disable verbose now.")
+endif
+
 # Beautify output
 # ---------------------------------------------------------------------------
 #
diff --git a/xen/Rules.mk b/xen/Rules.mk
index 48ae519d0153..c313486ce0f6 100644
--- a/xen/Rules.mk
+++ b/xen/Rules.mk
@@ -9,28 +9,6 @@ include $(XEN_ROOT)/Config.mk
 include $(BASEDIR)/scripts/Kbuild.include
 
 
-ifneq ($(origin crash_debug),undefined)
-$(error "You must use 'make menuconfig' to enable/disable crash_debug now.")
-endif
-ifeq ($(origin debug),command line)
-$(warning "You must use 'make menuconfig' to enable/disable debug now.")
-endif
-ifneq ($(origin frame_pointer),undefined)
-$(error "You must use 'make menuconfig' to enable/disable frame_pointer now.")
-endif
-ifneq ($(origin kexec),undefined)
-$(error "You must use 'make menuconfig' to enable/disable kexec now.")
-endif
-ifneq ($(origin lock_profile),undefined)
-$(error "You must use 'make menuconfig' to enable/disable lock_profile now.")
-endif
-ifneq ($(origin perfc),undefined)
-$(error "You must use 'make menuconfig' to enable/disable perfc now.")
-endif
-ifneq ($(origin verbose),undefined)
-$(error "You must use 'make menuconfig' to enable/disable verbose now.")
-endif
-
 TARGET := $(BASEDIR)/xen
 
 # Note that link order matters!
-- 
Anthony PERARD