Bug#751800: mpg123: i486 decoder broken

[Simon Kirby]

Package: mpg123
Version: 1.18.0-1
Severity: minor
Tags: upstream

Hello! In 1.18.0 through SVN, a bug in the i486 decoder exists that
corrupts output on the right channel when using default options and the
output clips. I've opened an upstream bug report for this:
https://sourceforge.net/p/mpg123/bugs/209/

Meanwhile, I find debian/rules perplexing. When dpkg-architecture
-qDEB_HOST_ARCH returns "i386", no additional configuration options are
appended, and dh_auto_configure ends up passing --build=i486-linux-gnu to
configure, which is treated the same as --with-cpu=i486, which uses the
buggy decoder on 32-bit systems. If dpkg-architecture were to return i486
(when does this happen?), configure is passed --with-cpu=x86_dither,
which avoids the problem, but which is documents (in NEWS) as being for
i586 and above.

In the case of the original bug, --with-cpu=i386 avoids the decoder bug
(though this should eventually be fixed upstream), but it still seems odd
that debian/rules is checking for i486 to configure an i586 option.

Simon-

-- System Information:
Debian Release: jessie/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (1, 'experimental')
Architecture: i386 (x86_64)
Foreign Architectures: amd64

Kernel: Linux 3.15.0-rc5 (SMP w/4 CPU cores)
Locale: LANG=C, LC_CTYPE=C (charmap=ANSI_X3.4-1968)
Shell: /bin/sh linked to /bin/bash

Versions of packages mpg123 depends on:
ii  libc6        2.19-1
ii  libltdl7     2.4.2-1.7
ii  libmpg123-0  1.18.0-1

Versions of packages mpg123 recommends:
ii  libasound2                1.0.27.2-4
ii  libjack0 [libjack-0.116]  1:0.124.1+20140122git5013bed0-3
ii  libopenal1                1:1.14-4
ii  libportaudio2             19+svn20140130-1
ii  oss-compat                6

Versions of packages mpg123 suggests:
ii  alsa-utils  1.0.27.2-1
pn  jackd       <none>
pn  nas         <none>
ii  oss-compat  6
pn  oss4-base   <none>
pn  pulseaudio  <none>

-- debconf-show failed