From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [RFH] two and half potential fixlets to the in-core index
 handling
Date: Sat, 23 Aug 2008 12:14:55 -0700
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Cc: Paolo Bonzini <bonzini@gnu.org>,
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To: Linus Torvalds <torvalds@linux-foundation.org>
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In-Reply-To: <alpine.LFD.1.10.0808231104500.3363@nehalem.linux-foundation.org> (Linus
 Torvalds's message of "Sat, 23 Aug 2008 11:13:14 -0700 (PDT)")
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Linus Torvalds <torvalds@linux-foundation.org> writes:

> On Sat, 23 Aug 2008, Junio C Hamano wrote:
>> 
>> A hacky solution I have in the attached patch is to waste an xmalloc(1)
>> and store it there when o->result is created, and also make
>> read_from_index() pay attention to the cache_nr and the cache_changed
>> bit. I think it is the safest and minimum fix.
>
> Hmm. Wouldn't it be nicer to just add another bit to istate? We have the 
> space already, since we already have a bitfield there, with just one bit 
> used?

cache_changed can also become a single-bit field.

The oldest "the_index" users work from it in the BSS initialized all
zero.  We'd also need to mark it as initialized, wouldn't we?