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Date: Sun, 19 Sep 2010 14:23:02 +0200
From: Joerg Sonnenberger <joerg@britannica.bec.de>
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Subject: Re: ar(1) format_decimal failure is fatal?
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On Sat, Sep 18, 2010 at 12:01:04AM -0400, Benjamin Kaduk wrote:
> GNU binutils has recently (well, March 2009) added a -D
> ("deterministic") argument to ar(1) which sets the timestamp, uid,
> and gid to zero, and the mode to 644.

That argument was added based on discussions on NetBSD about doing
bit-identical release builds. It was made optional for the possible
users of the data, not that we are really aware of anyone using it.
The ar(1) support in make basically goes back to a time when replacing
the content was a major speed up for incremental builds and it is pretty
much useless nowadays. Similary the timestamp, it doesn't tell that much
about the content either.

I don't think the backend should do silent truncation, that would be
very bad. It might be needed to have a flag for backends to allow it
though.

Joerg