diff -u cwidget-0.5.16/debian/rules cwidget-0.5.16/debian/rules
--- cwidget-0.5.16/debian/rules
+++ cwidget-0.5.16/debian/rules
@@ -1,8 +1,5 @@
 #!/usr/bin/make -f
 
-# Work around build failure on ppc64 with -O3 -Werror.
-export DEB_GCC_NO_O3=1
-
 # We need fno-strict-aliasing because otherwise g++ throws an
 # inscrutable error; I'd rather fix the root cause, but I can't find
 # it.
@@ -13,10 +10,19 @@
   DEB_CXXFLAGS_MAINT_APPEND=-fno-strict-aliasing
 endif
 
+ifneq (,$(findstring nocheck,$(DEB_BUILD_OPTIONS)))
+  NOCHECK = yes
+endif
+
+ifneq ($(DEB_BUILD_GNU_TYPE),$(DEB_HOST_GNU_TYPE))
+  CROSS_CONFIGURE_OPTIONS = --build $(DEB_BUILD_GNU_TYPE) --host $(DEB_HOST_GNU_TYPE)
+  NOCHECK = yes
+endif
+
 configure: configure-stamp
 configure-stamp:
-	dh_autotools-dev_updateconfig
-	./configure --prefix=/usr $(shell dpkg-buildflags --export=configure)
+	dh_autoreconf
+	./configure --prefix=/usr $(shell dpkg-buildflags --export=configure) $(CROSS_CONFIGURE_OPTIONS)
 
 	touch configure-stamp
 
@@ -25,7 +31,9 @@
 	dh_testdir
 
 	$(MAKE)
+ifneq (yes,$(NOCHECK))
 	$(MAKE) check
+endif
 
 	touch build-stamp-arch
 
@@ -48,7 +56,7 @@
 	[ ! -f Makefile ] || $(MAKE) distclean
 
 	-rm -r doc/ikiwiki/.ikiwiki
-	dh_autotools-dev_restoreconfig
+	dh_autoreconf_clean
 	dh_clean
 
 
diff -u cwidget-0.5.16/debian/control cwidget-0.5.16/debian/control
--- cwidget-0.5.16/debian/control
+++ cwidget-0.5.16/debian/control
@@ -4,10 +4,10 @@
 Homepage: http://cwidget.alioth.debian.org
 XS-Debian-Vcs-Git: git://git.debian.org/git/cwidget/debian
 XS-Debian-Vcs-Browser: http://git.debian.org/?p=cwidget/debian/.git;a=summary
-Maintainer: Ubuntu Core Developers <ubuntu-devel-discuss@lists.ubuntu.com>
+Maintainer: Ubuntu Developers <ubuntu-devel-discuss@lists.ubuntu.com>
 XSBC-Original-Maintainer: Daniel Burrows <dburrows@debian.org>
 Build-Depends: debhelper (>= 5.0.0), libsigc++-2.0-dev,
- libncursesw5-dev, gettext, g++ (>= 4:3.2.2-0), libcppunit-dev, autotools-dev
+ libncursesw5-dev, gettext, g++ (>= 4:3.2.2-0), libcppunit-dev, dh-autoreconf
 Build-Depends-Indep: doxygen
 Standards-Version: 3.7.2.2
 
diff -u cwidget-0.5.16/debian/changelog cwidget-0.5.16/debian/changelog
--- cwidget-0.5.16/debian/changelog
+++ cwidget-0.5.16/debian/changelog
@@ -1,3 +1,26 @@
+cwidget (0.5.16-3.5ubuntu1) trusty; urgency=medium
+
+  * Resynchronise with Debian.  Remaining changes:
+    - Drop ikiwiki and libhtml-scrubber-perl build-deps (not in main) and
+      perlmagick build-dep (only used by ikiwiki).
+  * Drop workaround for -O3, no longer needed.
+  * Convert to dh-autoreconf in order to update libtool.m4 for new ports.
+  * Adjust header installation to work around strictness in new automake
+    that forbids the use of pkglib_HEADERS.
+  * Remove duplicates from widgetsinclude_HEADERS in
+    src/cwidget/widgets/Makefile.am.
+
+ -- Colin Watson <cjwatson@ubuntu.com>  Wed, 18 Dec 2013 14:47:38 +0000
+
+cwidget (0.5.16-3.5) unstable; urgency=low
+
+  * Non-maintainer upload.
+  * Support cross-building (thanks, Eleanor Chen; closes: #721357).
+  * Use the autotools-dev dh addon to update config.guess/config.sub for
+    arm64 (closes: #725913).
+
+ -- Colin Watson <cjwatson@debian.org>  Thu, 14 Nov 2013 10:02:05 +0000
+
 cwidget (0.5.16-3.4ubuntu2) saucy; urgency=low
 
   * Use the autotools-dev dh addon to update config.guess/config.sub for
only in patch2:
unchanged:
--- cwidget-0.5.16.orig/Makefile.am
+++ cwidget-0.5.16/Makefile.am
@@ -27,7 +27,8 @@
 
 pkgconfig_DATA = cwidget.pc
 
-pkglib_HEADERS = cwidget-config.h
+mypkglibdir = $(pkglibdir)
+mypkglib_HEADERS = cwidget-config.h
 
 doc ikiwiki doxygen: Doxyfile
 	$(MAKE) -C doc $@
only in patch2:
unchanged:
--- cwidget-0.5.16.orig/src/cwidget/widgets/Makefile.am
+++ cwidget-0.5.16/src/cwidget/widgets/Makefile.am
@@ -31,14 +31,7 @@
 	staticitem.h	\
 	size_box.h	\
 	stacked.h	\
-	radiogroup.h	\
-	statuschoice.h	\
-	scrollbar.h	\
-	passthrough.h	\
-	pager.h		\
-	multiplex.h	\
-	minibuf_win.h	\
-	menubar.h
+	radiogroup.h
 
 libwidgets_la_SOURCES = \
 	button.cc	\