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Date:	Tue, 20 Jan 2026 10:02:13 +0100
Message-Id:	<p9u01pjkveqy.fsf@araignee.loria.fr>
To:	KENNON J CONRAD <kennonconrad AT comcast DOT net>
Cc:	cygwin AT cygwin DOT com
In-Reply-To:	<335671721.621101.1768877396354@connect.xfinity.com> (message
	from KENNON J CONRAD on Mon, 19 Jan 2026 18:49:56 -0800 (PST))
Subject:	Re: Log2 seems inefficient
References:	<226987210 DOT 591128 DOT 1768766440723 AT connect DOT xfinity DOT com>
	<3c56778a-870c-4bae-a855-6b96392870c8 AT SystematicSW DOT ab DOT ca>
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From:	Paul Zimmermann via Cygwin <cygwin AT cygwin DOT com>
Reply-To:	Paul Zimmermann <Paul DOT Zimmermann AT inria DOT fr>
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       Hi Kennon,

> Thank you, Paul.  It looks like it would be worth a try as the current log2 implementation from Cygwin is clearly not optimal for either speed or accuracy.  This may be a stupid question, but what would be the easiest way to incorporate this into open source software?  Should I rename the function and copy the (slightly modified) source code into the distribution?

yes, the file is self-content, just rename cr_log2() into log2(),
making sure you keep the copyright paragraph at the beginning.

For ease of maintenance, also indicate which commit of CORE-MATH you used,
and document changes if you need some.

Feel free to contact us (core-math AT inria DOT fr) in case of problem.

Best regards,
Paul

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