Dpkg::Compression: add --no-name and --rsyncable options to the gzip call

Pass --no-name option to gzip to avoid encoding the timestamp in the file
so that the result is more predictable. Also pass --rsyncable to make
source packages more rsync friendly.

debian/changelog

@@ -46,6 +46,9 @@ dpkg (1.15.8) UNRELEASED; urgency=low
   * Add --export command to dpkg-buildflags to be used in shell with eval.
   * Modify source format "3.0 (git)" to use git bundles. Thanks to Joey Hess
     for the patch.
+  * Pass --no-name option to gzip to avoid encoding the timestamp in the file
+    so that the result is more predictable. Closes: #587724
+    Also pass --rsyncable to make source packages more rsync friendly.
 
   [ Guillem Jover ]
   * Require gettext 0.18:

scripts/Dpkg/Compression.pm

@@ -52,7 +52,7 @@ interact with the set of supported compression methods.
 my $COMP = {
     "gzip" => {
 	"file_ext" => "gz",
-	"comp_prog" => [ "gzip" ],
+	"comp_prog" => [ "gzip", "--no-name", "--rsyncable" ],
 	"decomp_prog" => [ "gunzip" ],
     },
     "bzip2" => {