diff --git a/xen-optimize.patch b/xen-optimize.patch
new file mode 100644
index 0000000..ba120b8
--- /dev/null
+++ b/xen-optimize.patch
@@ -0,0 +1,11 @@
+--- xen-4.1.2-testing/tools/blktap2/drivers/Makefile.orig	2012-07-29 13:02:16.275448839 +0200
++++ xen-4.1.2-testing/tools/blktap2/drivers/Makefile	2012-07-29 13:02:37.041208027 +0200
+@@ -9,7 +9,7 @@
+ LOCK_UTIL  = lock-util
+ INST_DIR   = $(SBINDIR)
+ 
+-CFLAGS    += -Werror -g -O0
++#CFLAGS    += -Werror -g -O0
+ CFLAGS    += -Wno-unused
+ CFLAGS    += -fno-strict-aliasing
+ CFLAGS    += -I$(BLKTAP_ROOT)/include -I$(BLKTAP_ROOT)/drivers
diff --git a/xen.changes b/xen.changes
index eb39a6b..13b9de1 100644
--- a/xen.changes
+++ b/xen.changes
@@ -1,3 +1,9 @@
+-------------------------------------------------------------------
+Sun Jul 29 11:19:53 UTC 2012 - aj@suse.de
+
+- Build all files with optimization (fortify source does not work
+  with -O0).
+
 -------------------------------------------------------------------
 Tue Jul 10 10:16:42 UTC 2012 - werner@suse.de
 
diff --git a/xen.spec b/xen.spec
index b87f60c..4f0b018 100644
--- a/xen.spec
+++ b/xen.spec
@@ -570,6 +570,7 @@ Patch1142:      xenpaging.qemu.flush-cache.patch
 # xenalyze
 Patch20000:     xenalyze.gcc46.patch
 # Build patch
+Patch99997:     xen-optimize.patch
 Patch99998:     tmp-initscript-modprobe.patch
 Patch99999:     tmp_build.patch
 Url:            http://www.cl.cam.ac.uk/Research/SRG/netos/xen/
@@ -1313,6 +1314,7 @@ tar xfj %{SOURCE2} -C $RPM_BUILD_DIR/%{xen_build_dir}/tools
 %patch1137 -p1
 %patch1142 -p1
 #
+%patch99997 -p1
 %patch99998 -p1
 %patch99999 -p1