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Date: Thu, 5 May 2016 04:37:25 +0300
From: Andrey Repin <anrdaemon AT yandex DOT ru>
Reply-To: cygwin AT cygwin DOT com
Message-ID: <139590677.20160505043725@yandex.ru>
To: Ken Brown <kbrown AT cornell DOT edu>, cygwin AT cygwin DOT com
Subject: Re: Deterministic builds
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References: <ff5f5b20-33e2-ef2d-012a-a9e02903ba21 AT cornell DOT edu>
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Greetings, Ken Brown!

> Is it possible to build an executable on Cygwin so that subsequent 
> builds (with no change in source) produce identical results?

General answer is "no". It is possible to build a consistent object binary,
but executable linked from it will be different on different systems, for
various reasons.

> Currently,
> the timestamp embedded in executables prevents this.  (I don't know if 
> that's the only obstacle.)

Timestamps are the least of your issues.
Think of things like stack allocation bases.

> My actual use case is that I'm building a package that produces a large
> number of executables.  If I make a change in one source file, I'd like 
> to be able to know which executables change.

If your interest is purely self-educational, you can limit the noise on a
particular given system. But I wouldn't try to make any universal claims if I
were you.


-- 
With best regards,
Andrey Repin
Thursday, May 5, 2016 04:32:14

Sorry for my terrible english...


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