dpkg-source: unpack additional tarballs in a deterministic order

Reported-by: Samuel Bronson <naesten@gmail.com>
Closes: #747148

debian/changelog

@@ -3,6 +3,10 @@ dpkg (1.17.10) UNRELEASED; urgency=low
   [ Updated manpages translations ]
   * German (Helge Kreutzmann).
 
+  [ Raphaël Hertzog ]
+  * Let dpkg-source unpack additional tarballs in a deterministic order.
+    Thanks to Samuel Bronson for the report. Closes: #747148
+
  -- Guillem Jover <guillem@debian.org>  Wed, 30 Apr 2014 08:56:29 +0200
 
 dpkg (1.17.9) unstable; urgency=high

scripts/Dpkg/Source/Package/V2.pm

@@ -158,7 +158,7 @@ sub do_extract {
     # that would be blindly followed when applying the patches
 
     # Extract additional orig tarballs
-    foreach my $subdir (keys %origtar) {
+    foreach my $subdir (sort keys %origtar) {
         my $file = $origtar{$subdir};
         info(_g('unpacking %s'), $file);
         if (-e "$newdirectory/$subdir") {