diff -ur xen-4.4.0.orig/Config.mk xen-4.4.0/Config.mk
--- xen-4.4.0.orig/Config.mk	2014-03-10 18:47:38.000000000 +0800
+++ xen-4.4.0/Config.mk	2014-03-23 21:54:07.327717400 +0800
@@ -13,8 +13,6 @@
 # fallback for older make
 realpath = $(wildcard $(foreach file,$(1),$(shell cd -P $(dir $(file)) && echo "$$PWD/$(notdir $(file))")))
 
--include $(XEN_ROOT)/.config
-
 # A debug build of Xen and tools?
 debug ?= n
 debug_symbols ?= $(debug)
@@ -36,7 +34,7 @@
 
 # Tools to run on system hosting the build
 HOSTCC      = gcc
-HOSTCFLAGS  = -Wall -Werror -Wstrict-prototypes -O2 -fomit-frame-pointer
+HOSTCFLAGS  = -Wstrict-prototypes -O2 -fomit-frame-pointer
 HOSTCFLAGS += -fno-strict-aliasing
 
 DISTDIR     ?= $(XEN_ROOT)/dist
@@ -187,7 +185,7 @@
 
 CFLAGS += -std=gnu99
 
-CFLAGS += -Wall -Wstrict-prototypes
+CFLAGS += -Wstrict-prototypes
 
 # Clang complains about macros that expand to 'if ( ( foo == bar ) ) ...'
 # and is over-zealous with the printf format lint
diff -ur xen-4.4.0.orig/extras/mini-os/minios.mk xen-4.4.0/extras/mini-os/minios.mk
--- xen-4.4.0.orig/extras/mini-os/minios.mk	2014-03-10 18:43:57.000000000 +0800
+++ xen-4.4.0/extras/mini-os/minios.mk	2014-03-23 21:48:41.110722054 +0800
@@ -6,7 +6,7 @@
 
 # Define some default flags.
 # NB. '-Wcast-qual' is nasty, so I omitted it.
-DEF_CFLAGS += -fno-builtin -Wall -Werror -Wredundant-decls -Wno-format -Wno-redundant-decls
+DEF_CFLAGS += -fno-builtin -Wall -Wredundant-decls -Wno-format -Wno-redundant-decls
 DEF_CFLAGS += $(call cc-option,$(CC),-fno-stack-protector,)
 DEF_CFLAGS += $(call cc-option,$(CC),-fgnu89-inline)
 DEF_CFLAGS += -Wstrict-prototypes -Wnested-externs -Wpointer-arith -Winline
diff -ur xen-4.4.0.orig/tools/blktap2/drivers/Makefile xen-4.4.0/tools/blktap2/drivers/Makefile
--- xen-4.4.0.orig/tools/blktap2/drivers/Makefile	2014-03-10 18:43:57.000000000 +0800
+++ xen-4.4.0/tools/blktap2/drivers/Makefile	2014-03-23 21:55:52.215715903 +0800
@@ -9,7 +9,7 @@
 LOCK_UTIL  = lock-util
 INST_DIR   = $(SBINDIR)
 
-CFLAGS    += -Werror -g
+CFLAGS    += -g
 CFLAGS    += -Wno-unused
 CFLAGS    += -fno-strict-aliasing
 CFLAGS    += -I$(BLKTAP_ROOT)/include -I$(BLKTAP_ROOT)/drivers
diff -ur xen-4.4.0.orig/tools/debugger/gdbsx/Rules.mk xen-4.4.0/tools/debugger/gdbsx/Rules.mk
--- xen-4.4.0.orig/tools/debugger/gdbsx/Rules.mk	2014-03-10 18:43:57.000000000 +0800
+++ xen-4.4.0/tools/debugger/gdbsx/Rules.mk	2014-03-23 21:56:21.399715487 +0800
@@ -1,4 +1,4 @@
 include $(XEN_ROOT)/tools/Rules.mk
 
-CFLAGS   += -Werror -Wmissing-prototypes 
+CFLAGS   += -Wmissing-prototypes 
 # (gcc 4.3x and later)   -Wconversion -Wno-sign-conversion
diff -ur xen-4.4.0.orig/tools/firmware/Rules.mk xen-4.4.0/tools/firmware/Rules.mk
--- xen-4.4.0.orig/tools/firmware/Rules.mk	2014-03-10 18:43:57.000000000 +0800
+++ xen-4.4.0/tools/firmware/Rules.mk	2014-03-23 22:30:36.056686174 +0800
@@ -11,7 +11,7 @@
 CFLAGS += -DNDEBUG
 endif
 
-CFLAGS += -Werror
+CFLAGS +=
 
 $(call cc-options-add,CFLAGS,CC,$(EMBEDDED_EXTRA_CFLAGS))
 
diff -ur xen-4.4.0.orig/tools/libfsimage/Rules.mk xen-4.4.0/tools/libfsimage/Rules.mk
--- xen-4.4.0.orig/tools/libfsimage/Rules.mk	2014-03-10 18:43:57.000000000 +0800
+++ xen-4.4.0/tools/libfsimage/Rules.mk	2014-03-23 21:57:21.767714626 +0800
@@ -1,7 +1,7 @@
 include $(XEN_ROOT)/tools/Rules.mk
 
 CFLAGS += -Wno-unknown-pragmas -I$(XEN_ROOT)/tools/libfsimage/common/ -DFSIMAGE_FSDIR=\"$(FSDIR)\"
-CFLAGS += -Werror -D_GNU_SOURCE
+CFLAGS += -D_GNU_SOURCE
 LDFLAGS += -L../common/
 
 PIC_OBJS := $(patsubst %.c,%.opic,$(LIB_SRCS-y))
diff -ur xen-4.4.0.orig/tools/libxc/Makefile xen-4.4.0/tools/libxc/Makefile
--- xen-4.4.0.orig/tools/libxc/Makefile	2014-03-10 18:43:57.000000000 +0800
+++ xen-4.4.0/tools/libxc/Makefile	2014-03-23 21:49:37.919721243 +0800
@@ -87,7 +87,7 @@
 
 -include $(XEN_TARGET_ARCH)/Makefile
 
-CFLAGS   += -Werror -Wmissing-prototypes
+CFLAGS   += -Wmissing-prototypes
 CFLAGS   += -I. $(CFLAGS_xeninclude)
 
 # Needed for posix_fadvise64() in xc_linux.c
diff -ur xen-4.4.0.orig/tools/libxl/Makefile xen-4.4.0/tools/libxl/Makefile
--- xen-4.4.0.orig/tools/libxl/Makefile	2014-03-10 18:43:57.000000000 +0800
+++ xen-4.4.0/tools/libxl/Makefile	2014-03-23 21:58:09.983713938 +0800
@@ -11,7 +11,7 @@
 XLUMAJOR = 4.3
 XLUMINOR = 0
 
-CFLAGS += -Werror -Wno-format-zero-length -Wmissing-declarations \
+CFLAGS += -Wno-format-zero-length -Wmissing-declarations \
 	-Wno-declaration-after-statement -Wformat-nonliteral
 CFLAGS += -I. -fPIC
 
diff -ur xen-4.4.0.orig/tools/qemu-xen/pc-bios/optionrom/Makefile xen-4.4.0/tools/qemu-xen/pc-bios/optionrom/Makefile
--- xen-4.4.0.orig/tools/qemu-xen/pc-bios/optionrom/Makefile	2014-02-06 00:59:14.000000000 +0800
+++ xen-4.4.0/tools/qemu-xen/pc-bios/optionrom/Makefile	2014-03-23 21:59:13.175713036 +0800
@@ -9,7 +9,7 @@
 
 .PHONY : all clean build-all
 
-CFLAGS := -Wall -Wstrict-prototypes -Werror -fomit-frame-pointer -fno-builtin
+CFLAGS := -Wall -Wstrict-prototypes -fomit-frame-pointer -fno-builtin
 CFLAGS += -I$(SRC_PATH)
 CFLAGS += $(call cc-option, $(CFLAGS), -fno-stack-protector)
 QEMU_CFLAGS = $(CFLAGS)
diff -ur xen-4.4.0.orig/tools/tests/mce-test/tools/Makefile xen-4.4.0/tools/tests/mce-test/tools/Makefile
--- xen-4.4.0.orig/tools/tests/mce-test/tools/Makefile	2014-03-10 18:43:57.000000000 +0800
+++ xen-4.4.0/tools/tests/mce-test/tools/Makefile	2014-03-23 22:28:45.160687756 +0800
@@ -1,7 +1,7 @@
 XEN_ROOT=$(CURDIR)/../../../..
 include $(XEN_ROOT)/tools/Rules.mk
 
-CFLAGS += -Werror
+CFLAGS +=
 CFLAGS += $(CFLAGS_libxenctrl)
 CFLAGS += $(CFLAGS_libxenguest)
 CFLAGS += $(CFLAGS_libxenstore) 
diff -ur xen-4.4.0.orig/tools/tests/mem-sharing/Makefile xen-4.4.0/tools/tests/mem-sharing/Makefile
--- xen-4.4.0.orig/tools/tests/mem-sharing/Makefile	2014-03-10 18:43:57.000000000 +0800
+++ xen-4.4.0/tools/tests/mem-sharing/Makefile	2014-03-23 22:29:15.472687324 +0800
@@ -1,7 +1,7 @@
 XEN_ROOT=$(CURDIR)/../../..
 include $(XEN_ROOT)/tools/Rules.mk
 
-CFLAGS += -Werror
+CFLAGS +=
 
 CFLAGS += $(CFLAGS_libxenctrl)
 CFLAGS += $(CFLAGS_xeninclude)
diff -ur xen-4.4.0.orig/tools/tests/xen-access/Makefile xen-4.4.0/tools/tests/xen-access/Makefile
--- xen-4.4.0.orig/tools/tests/xen-access/Makefile	2014-03-10 18:43:57.000000000 +0800
+++ xen-4.4.0/tools/tests/xen-access/Makefile	2014-03-23 22:30:02.064686659 +0800
@@ -1,8 +1,6 @@
 XEN_ROOT=$(CURDIR)/../../..
 include $(XEN_ROOT)/tools/Rules.mk
 
-CFLAGS += -Werror
-
 CFLAGS += $(CFLAGS_libxenctrl)
 CFLAGS += $(CFLAGS_libxenguest)
 CFLAGS += $(CFLAGS_xeninclude)
diff -ur xen-4.4.0.orig/tools/xenstat/xentop/Makefile xen-4.4.0/tools/xenstat/xentop/Makefile
--- xen-4.4.0.orig/tools/xenstat/xentop/Makefile	2014-03-10 18:43:57.000000000 +0800
+++ xen-4.4.0/tools/xenstat/xentop/Makefile	2014-03-23 22:23:59.944691825 +0800
@@ -18,7 +18,7 @@
 all install xentop:
 else
 
-CFLAGS += -DGCC_PRINTF -Wall -Werror $(CFLAGS_libxenstat)
+CFLAGS += -DGCC_PRINTF -Wall $(CFLAGS_libxenstat)
 LDLIBS += $(LDLIBS_libxenstat) $(CURSES_LIBS) $(SOCKET_LIBS)
 CFLAGS += -DHOST_$(XEN_OS)