Revert libevent to 1.4.12 - symbol export regression 'event_sigcb'

[Chris J]

libevent 1.4.13 has lost a symbol 'event_sigcb' which is causing other programs to break. There is disagreement from upstream as to whether the symbol should ever have been exported in the first place, however, it appears that it was and still is other software is relying on it. This will apparently come back in the next upstream release, however, there is no timescale on its release. In the meantime, this should be reverted to a version containing the symbol to avoid breaking other things.

[Michiel Eghuizen (michieleghuizen)]

See also: http://sourceforge.net/tracker/index.php?func=detail&aid=2909223&group_id=50884&atid=461322

The symbol was never meant to be exported, what you're already saying. The software relying on it should be fixed, not libevent.

[Chris J (chriscf)]

Unfortunately, it doesn't really matter whether they wanted it in there or not, the simple fact is that having other software rely on it has effectively made it a part of the public interface which needs to be maintained for backward compatibility. I suspect this is one reason why it will be available in the next upstream release (and is in fact already back in their repository), but as previously stated we have no idea when that's coming.

If this were any other release, I might concur with "fix other stuff", but this is an LTS. If this package has caused a regression, we're stuck with it for _five years_.