non-deterministic compression for CREDITS.gz in libppl9 amd64 & armel

[Neil Williams]

$ dget 
http://ftp.uk.debian.org/debian/pool/main/p/ppl/libppl9_0.11.2-6_armel.deb
$ dpkg -X libppl9_0.11.2-6_armel.deb .
$ cp ./usr/share/doc/libppl9/CREDITS.gz .

$ md5sum CREDITS.gz 
0e52e84eebf41588865742edaff7b3c0  CREDITS.gz
$ gunzip CREDITS.gz 
$ gzip -9nf CREDITS 
$ md5sum CREDITS.gz 
99e2b9f8972ce00cfe57e3735881015e  CREDITS.gz

This test was done on abel.debian.org - an armel machine using gzip
1.3.12-9 but the original armel package was built using gzip 1.4-1 on
the buildd.

(This md5sum matches that of the same file in the amd64 package.)
http://ftp.uk.debian.org/debian/pool/main/p/ppl/libppl9_0.11.2-6_amd64.deb
99e2b9f8972ce00cfe57e3735881015e  usr/share/doc/libppl9/CREDITS.gz

$ od -tx1 < CREDITS.gz > CREDITS-redone.gz.od
$ od -tx1 < ./usr/share/doc/libppl9/CREDITS.gz > CREDITS-original.gz.od
$ diff -u CREDITS-original.gz.od CREDITS-redone.gz.od
--- CREDITS-original.gz.od      2012-02-06 20:34:43.000000000 +0000
+++ CREDITS-redone.gz.od        2012-02-06 20:34:29.000000000 +0000
@@ -393,6 +393,6 @@
 0014200 16 78 3d a3 79 3d 1c f0 b0 c2 5f e9 f6 0b 5b 4c
 0014220 77 8b 91 89 1d 13 b7 58 16 f3 5b 10 1e 20 d1 f3
 0014240 d3 44 79 f2 05 9a 9c e7 87 42 b9 b5 34 42 56 55
-0014260 95 a1 bb 55 ec 78 cb f2 7f ba 11 41 f7 b3 d4 0f
-0014300 d6 b0 a7 11 7b 4c 00 00
-0014310
+0014260 95 a1 bb 55 ec 78 cb f2 7f ba 11 41 f7 ea 3f d6
+0014300 b0 a7 11 7b 4c 00 00
+0014307

i.e. the armel package contains the anomalous file but it can be
converted to the same file as the amd64 package by redoing the
compression.

The manifestation of this bug is clear when trying to install the
MultiArch build-dependencies for cross-compilers:

$ sudo apt-get install libcloog-ppl-dev:armel

Selecting previously unselected package libppl9:armel.
(Reading database ... 167711 files and directories currently installed.)
Unpacking libppl9:armel (from .../libppl9_0.11.2-6_armel.deb) ...
dpkg: error processing /var/cache/apt/archives/libppl9_0.11.2-6_armel.deb 
(--unpack):
 './usr/share/doc/libppl9/CREDITS.gz' is different from the same file on the 
system


-- 


Neil Williams
=============
http://www.linux.codehelp.co.uk/

pgpE_0tBF8jfo.pgp
Description: PGP signature