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From: Ludovic Brenta <ludovic@ludovic-brenta.org>
Newsgroups: comp.lang.ada
Subject: Re: Implementing an Ada compiler and libraries.
References: <1178721451.073700.10730@y80g2000hsf.googlegroups.com>
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	<87wszgocrj.fsf@ludovic-brenta.org> <46435866.9090301@obry.net>
Date: Fri, 11 May 2007 12:09:16 +0200
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Pascal Obry writes:
> Ludovic Brenta a écrit :
>> That's what GNAT does, only it uses a simple checksum for performance
>> reasons.  Calculating the checksum and comparing it with the one in
>> the library (.ali files in the case of GNAT) has to be faster than
>> recompiling the file.
>
> No that's not a simple checksum since some time. It is now using md5.

CRC32, by the looks of scng.adb (see Accumulate_Checksum).  I do think
that md5 would be overkill.

-- 
Ludovic Brenta.