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Date: Sun, 11 Sep 2011 11:47:38 +0300
From: Andriy Gapon <avg@FreeBSD.org>
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Cc: Alexander Kabaev <kan@FreeBSD.org>, freebsd-current@FreeBSD.org
Subject: Re: ZFS: i/o error - all block copies unavailable after upgrading
 to r225312
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on 11/09/2011 11:31 Andriy Gapon said the following:
> And I am actually wondering about -fno-unit-at-a-time option.
> In my opinion this is an anti-optimization option and it can actually increase
> a size of a final binary.  In fact, it looks like the option was introduced to
> boot2 in r132870 in the year 2004, way before GCC 4.X switch, and it was
> introduced to avoid some optimizations that produced broken code.
> I wonder if there is any reason to keep using that option now.
> 
> At least the zfs boot code works fine without the option in my testing.

And it looks like -fno-toplevel-reorder can be used instead of
-fno-unit-at-a-time if we really depend on preserving the order:
http://gcc.gnu.org/gcc-4.2/changes.html

-- 
Andriy Gapon