diff -Nru valgrind-3.16.1/debian/changelog valgrind-3.16.1/debian/changelog
--- valgrind-3.16.1/debian/changelog	2020-06-29 02:49:18.000000000 +0900
+++ valgrind-3.16.1/debian/changelog	2020-12-09 09:17:53.000000000 +0900
@@ -1,3 +1,16 @@
+valgrind (1:3.16.1-1.deb8moz1) jessie; urgency=medium
+
+  * Mozilla backport for jessie.
+  * debian/control, debian/compat: Drop debhelper compat back to 9, which
+    requires adding back an explicit dependency on dh-autoreconf.
+  * debian/rules:
+    - Debhelper only defaulted to --parallel in compat >= 10, so add
+      --parallel back.
+    - Add an explicit --libexecdir to match that of debhelper compat level >=
+      12.
+
+ -- Mike Hommey <glandium@mozilla.com>  Wed, 9 Dec 2020 09:17:53 +0900
+
 valgrind (1:3.16.1-1) unstable; urgency=medium
 
   * New upstream release
diff -Nru valgrind-3.16.1/debian/compat valgrind-3.16.1/debian/compat
--- valgrind-3.16.1/debian/compat	1970-01-01 09:00:00.000000000 +0900
+++ valgrind-3.16.1/debian/compat	2020-12-09 09:15:49.000000000 +0900
@@ -0,0 +1 @@
+9
diff -Nru valgrind-3.16.1/debian/control valgrind-3.16.1/debian/control
--- valgrind-3.16.1/debian/control	2020-06-29 02:49:18.000000000 +0900
+++ valgrind-3.16.1/debian/control	2020-12-09 09:17:53.000000000 +0900
@@ -2,7 +2,8 @@
 Section: devel
 Priority: optional
 Maintainer: Alessandro Ghedini <ghedo@debian.org>
-Build-Depends: debhelper-compat (= 13),
+Build-Depends: debhelper (>= 9),
+ dh-autoreconf,
  gdb,
  gcc-multilib [amd64],
  libc6-dev-i386 [amd64],
diff -Nru valgrind-3.16.1/debian/rules valgrind-3.16.1/debian/rules
--- valgrind-3.16.1/debian/rules	2020-06-29 02:49:18.000000000 +0900
+++ valgrind-3.16.1/debian/rules	2020-12-09 09:17:53.000000000 +0900
@@ -11,16 +11,16 @@
 LDFLAGS  = $(shell dpkg-buildflags --get LDFLAGS)
 
 %:
-	dh $@ --with=autoreconf
+	dh $@ --parallel --with=autoreconf
 
 override_dh_auto_configure:
-	dh_auto_configure -- --enable-tls CFLAGS="$(CFLAGS)" LDFLAGS="$(LDFLAGS)"
+	dh_auto_configure -- --libexecdir=/usr/libexec --enable-tls CFLAGS="$(CFLAGS)" LDFLAGS="$(LDFLAGS)"
 
 override_dh_auto_test:
 	: # do nothing for now
 
 override_dh_auto_build:
-	dh_auto_build
+	dh_auto_build --parallel
 	$(MAKE) -C docs FAQ.txt
 	$(MAKE) -C docs html-docs
 	$(MAKE) -C docs man-pages