do-release-upgrade crashed with UnicodeDecodeError in __main__: 'ascii' codec can't decode byte 0xc3 in position 36: ordinal not in range(128)

Were you just running this command in a terminal while an upgrade was in progress in order to produce the crash?
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Ubuntu Bug Squad volunteer triager
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No - no upgrade in the background. This is still reproducible. Did you try running the command?

Yes I ran the command without an issue. I was just wondering if you had run it while there was an update in progress with the update-manager. If thats the case I will try running the command again while an update is going.
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Ubuntu Bug Squad volunteer triager
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No, there was no update in progress. I use a German locale normally - I don't know if that has anything to do with it. Did you try it on Ubuntu 12.04?

Thanks for your report Daniel.

This is reproducible by installing a German locale then running:
LANGUAGE=de:en LC_ALL=C do-release-upgrade --help

(which is how the system is set according to proc/environ)

I'm not sure this is actually a bug to be fixed. LC_ALL=C means that LC_CTYPE is also set to C; that's a declaration that you only want ascii output, but the language setting asks the application to use the German translation if available - which it obviously is, and evidently contains non-ascii characters.

So while we could fix the code to avoid a backtrace, none of the available options seem more correct. Outputting the text in UTF-8 means ignoring the locale setting; dropping the non-ascii characters means a garbled translation.

Daniel, is this really an issue specific to do-release-upgrade? Does other command-line software generally get translated correctly for you with these settings?

Note that you can set LC_ALL=C.UTF-8 to get the relevant C locale semantics but with a UTF-8 charset.

I believe I fixed in the process of fixing some other translation issues. Could you please test this again in Quantal? Thanks in advance.

Still a problem:

daniel@daydream:~$ LC_ALL=C do-release-upgrade --help
Traceback (most recent call last):
  File "/usr/bin/do-release-upgrade", line 100, in <module>
    (options, args) = parser.parse_args()
  File "/usr/lib/python3.2/optparse.py", line 1388, in parse_args
    stop = self._process_args(largs, rargs, values)
  File "/usr/lib/python3.2/optparse.py", line 1428, in _process_args
    self._process_long_opt(rargs, values)
  File "/usr/lib/python3.2/optparse.py", line 1503, in _process_long_opt
    option.process(opt, value, values, self)
  File "/usr/lib/python3.2/optparse.py", line 786, in process
    self.action, self.dest, opt, value, values, parser)
  File "/usr/lib/python3.2/optparse.py", line 808, in take_action
    parser.print_help()
  File "/usr/lib/python3.2/optparse.py", line 1650, in print_help
    file.write(self.format_help())
UnicodeEncodeError: 'ascii' codec can't encode character '\xdf' in position 162: ordinal not in range(128)
daniel@daydream:~$

Reassigning to the ubuntu-release-upgrader package as it has been split out from update-manager in the Quantal cycle.