From mboxrd@z Thu Jan  1 00:00:00 1970
From: Matthieu Moy <Matthieu.Moy@imag.fr>
Subject: Re: git and mtime
Date: Thu, 20 Nov 2008 11:53:40 +0100
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Cc: Arafangion <thestar@fussycoder.id.au>,
	Roger Leigh <rleigh@codelibre.net>, git@vger.kernel.org
To: Johannes Schindelin <Johannes.Schindelin@gmx.de>
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In-Reply-To: <alpine.DEB.1.00.0811201132220.30769@pacific.mpi-cbg.de> (Johannes Schindelin's message of "Thu\, 20 Nov 2008 11\:34\:08 +0100 \(CET\)")
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Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:

> Hi,
>
> On Wed, 19 Nov 2008, Matthieu Moy wrote:
>
>> Arafangion <thestar@fussycoder.id.au> writes:
>> 
>> > You should probably fix your build script,
>> 
>> ccache should help:
>
> Only if you _allow_ the problem that makes ccache necessary.  Which we 
> don't.

You do, for some definition of "problem".

make
git checkout whatever
make
git checkout where-you-were-before
make # <--- this one

The last make is correct with plain git and plain make, but it can be
slow. With a cache in your build system, it can just reuse the objects
created during the first "make". It doesn't change correctness, only
performance.

-- 
Matthieu