From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,FREEMAIL_FROM autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 1014db,582dff0b3f065a52 X-Google-Attributes: gid1014db,public X-Google-Thread: 103376,bc1361a952ec75ca X-Google-Attributes: gid103376,public X-Google-Thread: 109fba,582dff0b3f065a52 X-Google-Attributes: gid109fba,public X-Google-ArrivalTime: 2001-08-27 20:33:03 PST Path: archiver1.google.com!newsfeed.google.com!newsfeed.stanford.edu!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!jfk3-feed1.news.digex.net!intermedia!tor-nx1.netcom.ca!tor-nn1.netcom.ca.POSTED!not-for-mail Message-ID: <3B8B1130.97FFDD66@yahoo.com> From: Joe Maun Organization: H X-Mailer: Mozilla 4.77 [en] (Win95; U) X-Accept-Language: en MIME-Version: 1.0 Newsgroups: comp.lang.ada,comp.lang.c,comp.lang.c++ Subject: Re: Subtle Bugs, kudos Ada (was How Ada ...Red Code ...) References: <3B6555ED.9B0B0420@sneakemail.com> <87n15lxzzv.fsf@deneb.enyo.de> <3B672322.B5EA1B66@home.com> <4a885870.0108112341.7ce02ac0@posting.google.com> <3B834E5D.B0D26AB1@adaworks.com> <9lvsic$bet9s$1@ID-9852.news.dfncis.de> <9m0193$grs$1@bird.wu-wien.ac.at> <3B83F042.4CFB073D@home.com> <3B8462C8.5596C089@yahoo.com> <87n14nmbf8.fsf@deneb.enyo.de> <3B89A809.46083436@yahoo.com> <871ylxpxu6.fsf@deneb.enyo.de> <3B8AA131.3FCC0E9A@yahoo.com> <87g0ad44ab.fsf@deneb.enyo.de> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Date: Mon, 27 Aug 2001 23:34:08 -0400 NNTP-Posting-Host: 216.123.134.217 X-Complaints-To: abuse@attcanada.ca X-Trace: tor-nn1.netcom.ca 998969577 216.123.134.217 (Mon, 27 Aug 2001 23:32:57 EDT) NNTP-Posting-Date: Mon, 27 Aug 2001 23:32:57 EDT Xref: archiver1.google.com comp.lang.ada:12499 comp.lang.c:77153 comp.lang.c++:86119 Date: 2001-08-27T23:34:08-04:00 List-Id: Florian Weimer wrote: > > Joe Maun writes: > > > I fail to see your point. Why wouldn't the sign bit be shifted right in > > sign magnitude representation? The quote from the standard above seems > > clear - and it applies to a signed magnitude implementation as well. > > What about this quote from the standard, then? > > | 3.4.1 > | [#1] implementation-defined behavior > | unspecified behavior where each implementation documents how > | the choice is made > | > | [#2] EXAMPLE An example of implementation-defined behavior > | is the propagation of the high-order bit when a signed > | integer is shifted right. I'm afraid you missed the point. As has already been pointed out, the discussion isn't about the new high-order bits that the shift introduces, which is what the quote above mentions. Everybody agrees that that's implementation defined. The question is what about the bits that already exist - are they guaranteed to be reliably shifted right? I say yes, some say no. If anything, the quote above strongly hints that the intention of the standard is as I argue, since it only mentions the propagation of the _high order bit_ as implementation defined. -- Joe Maun Montreal, QC Canada