<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">llogb and ilogb return in integer format, so we don’t need to say anything about the sign of a zero result for them. <div class=""><br class=""></div><div class="">For logb we do seem to be missing specification for the sign of a zero result. 754 says</div><div class=""><br class=""></div><blockquote style="margin: 0 0 0 40px; border: none; padding: 0px;" class=""><div class="">logB(1) is +0.</div></blockquote><div class=""><br class=""></div><div class="">Shouldn’t that be</div><div class=""><br class=""></div><div class=""><blockquote style="margin: 0px 0px 0px 40px; border: none; padding: 0px;" class="">logB(+/-1) is +0.</blockquote></div><div class=""><br class=""></div><div class="">Whichever, we could add an equivalent statement in F.10.3.11.</div><div class=""><br class=""></div><div class="">Alternatively, we could add something in 7.12.6.11, though would have to account for the possibility of unsigned zeros. Maybe</div><div class=""><br class=""></div><blockquote style="margin: 0 0 0 40px; border: none; padding: 0px;" class=""><div class="">If the argument is +/-1, the result is positive or unsigned zero.</div></blockquote><div class=""><br class=""></div><div class=""><br class=""></div><div class="">- Jim Thomas<br class=""><div><br class=""><blockquote type="cite" class=""><div class="">On Aug 3, 2018, at 1:35 PM, Fred J. Tydeman <<a href="mailto:tydeman@tybor.com" class="">tydeman@tybor.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="">Do we need to add words along the lines of:<br class=""><br class="">llogb(1.) is +0L<br class="">ilogb(1.) is +0<br class="">logb(1.) is +0.0 if signed zeros are supported, otherwise, unsigned zero.<br class=""><br class="">This is a IEEE-754 requirement.<br class=""><br class=""><br class="">---<br class="">Fred J. Tydeman Tydeman Consulting<br class=""><a href="mailto:tydeman@tybor.com" class="">tydeman@tybor.com</a> Testing, numerics, programming<br class="">+1 (702) 608-6093 Vice-chair of PL22.11 (ANSI "C")<br class="">Sample C99+FPCE tests: <a href="http://www.tybor.com" class="">http://www.tybor.com</a><br class="">Savers sleep well, investors eat well, spenders work forever.<br class=""><br class="">_______________________________________________<br class="">Cfp-interest mailing list<br class=""><a href="mailto:Cfp-interest@oakapple.net" class="">Cfp-interest@oakapple.net</a><br class="">http://mailman.oakapple.net/mailman/listinfo/cfp-interest<br class=""></div></div></blockquote></div><br class=""></div></body></html>