From 8aea14bbd20b04b8fffaf35138ebdcbd39e433a3 Mon Sep 17 00:00:00 2001
From: "Yann E. MORIN" <yann.morin.1998@free.fr>
Date: Sat, 29 Oct 2016 16:35:26 +0200
Subject: [PATCH] xen/Rules.mk: fix build with CFLAGS from environment

When CFLAGS are passed from the environment, the first-level make
invocation will append -D__OBJECT_FILE__ to it, then call a second
make invocation, that will have those new CFLAGS in its environment,
but will also append -D__OBJECT_FILE__ to those.

Then, the compiler fails because __OBEJECT_FILE__ is defined twice.

Just undefine it before defining it again, as a *workaround* to this
issue.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
---
 xen/Rules.mk | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/xen/Rules.mk b/xen/Rules.mk
index 3090ea7828..d535bf9e2f 100644
--- a/xen/Rules.mk
+++ b/xen/Rules.mk
@@ -61,7 +61,7 @@ CFLAGS += -Werror -Wredundant-decls -Wno-pointer-arith
 $(call cc-option-add,CFLAGS,CC,-Wvla)
 CFLAGS += -pipe -D__XEN__ -include $(BASEDIR)/include/xen/config.h
 CFLAGS-$(CONFIG_DEBUG_INFO) += -g
-CFLAGS += '-D__OBJECT_FILE__="$@"'
+CFLAGS += -U__OBJECT_FILE__ '-D__OBJECT_FILE__="$@"'
 
 ifneq ($(clang),y)
 # Clang doesn't understand this command line argument, and doesn't appear to
-- 
2.22.0