Date: Wed, 08 May 2019 20:16:50 +0000 From: bugzilla-noreply@freebsd.org To: numerics@FreeBSD.org Subject: [Bug 237800] pow(3) returns inaccurate results Message-ID: <bug-237800-18636-R8M7CtVYjJ@https.bugs.freebsd.org/bugzilla/> In-Reply-To: <bug-237800-18636@https.bugs.freebsd.org/bugzilla/> References: <bug-237800-18636@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=237800 --- Comment #4 from sgk@troutmask.apl.washington.edu --- When you say you get the correct value on Linux, are you using clang 8.0.0 on Linux or some version of gcc? gcc will constant fold pow(10,29) using MPFR. Clang will generated a call to pow() in libm. In any event, the library is computing pow(10,29) as exp(29*log(10)) where special polynomial approximations are being used. With a ULP of 0.51, I suppose reading Goldberg's paper is merited. -- You are receiving this mail because: You are the assignee for the bug.
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