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From: | Martin Stromberg <eplmst AT lu DOT erisoft DOT se> |
Message-Id: | <200101120636.HAA14898@lws256.lu.erisoft.se> |
Subject: | Re: Weird results of log( -1.0 ) with libm.a and without libm.a (fwd) |
To: | djgpp-workers AT delorie DOT com |
Date: | Fri, 12 Jan 2001 07:36:04 +0100 (MET) |
In-Reply-To: | <Pine.SUN.3.91.1010111191955.20014B-100000@is> from "Eli Zaretskii" at Jan 11, 2001 07:25:04 PM |
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> > Someone complained about log() from libm producing -Inf for a negative > argument. It turns out that this is what the code is supposed to do, and > it is even documented in libm.info (type "info libm log"). > > Does anyone has an idea why this is the Right Thing to do? C89 says in 7.5.1: "On a domain error, the function returns an implementation-defined value, the value of the macro EDOM is stored in errno." So there does not seem to be any problem returning -Inf. Right, MartinS
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