From -6274212024486958478 X-Google-Thread: f78e5,174aa7b34b06a51 X-Google-Attributes: gidf78e5,public X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news1.google.com!news4.google.com!news.glorb.com!newsgate.cistron.nl!news.tele.dk!news.tele.dk!small.news.tele.dk!newsfeed.icl.net!newsfeed.fjserv.net!peer-uk.news.demon.net!kibo.news.demon.net!news.demon.co.uk!demon!stump.algebra.com!devnull From: bop@gmb.dk ("Bo Persson") Newsgroups: comp.std.c++ Subject: Re: Is this really unspecified behavior? Date: Wed, 7 Dec 2005 03:33:39 GMT Lines: 41 Sender: mail2news@demon.net Approved: fjh@cs.mu.oz.au (Fergus Henderson , moderator of comp.std.c++) Message-ID: <3vlsa2F16leqsU1@individual.net> References: <1132629737.664847.151630@o13g2000cwo.googlegroups.com> <1132662585.882464.24110@f14g2000cwb.googlegroups.com> <1132759176.368850.264850@g43g2000cwa.googlegroups.com> <1132933832.802917.153350@g14g2000cwa.googlegroups.com> <1133551647.532929.325730@z14g2000cwz.googlegroups.com> <1133583412.951239.208510@g49g2000cwa.googlegroups.com> NNTP-Posting-Host: news.news.demon.net X-Trace: news.demon.co.uk 1133926433 21942 158.152.254.254 (7 Dec 2005 03:33:53 GMT) X-Complaints-To: abuse@demon.net NNTP-Posting-Date: Wed, 7 Dec 2005 03:33:53 +0000 (UTC) X-Robomod: STUMP, ichudov@algebra.com (Igor Chudov) X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2670 X-Priority: 3 X-Greylisting: NO DELAY (Relay+Sender autoqualified); processed by UCSD_GL-v2.1 on mailbox8.ucsd.edu; Tue, 06 December 2005 08:24:36 -0800 (PST) X-Orig-X-Trace: individual.net hXT3krZHnybPDer3WhEJjgyx7T+myVMSD380TsJ8KRXt7L2VZv X-RFC2646: Format=Flowed; Response X-Virus-Scanned: amavisd-new at cs.mu.OZ.AU X-MSMail-Priority: Normal X-Received: (from fjh@localhost) by mulga.cs.mu.OZ.AU (8.12.10+Sun/8.12.9/Submit) id jB73XdOq004088; Wed, 7 Dec 2005 14:33:39 +1100 (EST) X-Path: comp-std-cpp-robomod!not-for-mail X-Delivered-To: std-c++@ucar.edu X-Spamscanner: mailbox8.ucsd.edu (v1.6 Aug 4 2005 15:27:38, 1.2/5.0 3.0.4) X-Authentication-Warning: mulga.cs.mu.OZ.AU: fjh set sender to devnull@stump.algebra.com using -f X-Newsreader: Microsoft Outlook Express 6.00.2900.2670 X-Newsgroups: comp.std.c++ X-MailScanner: PASSED (v1.2.8 13801 jB6GOY3p034399 mailbox8.ucsd.edu) Xref: g2news1.google.com comp.std.c++:2671 "Hyman Rosen" skrev i meddelandet news:E1EjGBD-0005T8-00@chx400.switch.ch... > kuyper@wizard.net wrote: >>>I think it would be helpful for your cause to list those >>>widely-used >>>idioms. Personally, I can't think of a widely-used idiom that >>>depends >>>on a particular evaluation order, and to the best of my knowledge >>>any >>>such idiom should merely be considered broken. However, if you know >>>of >>>any such idioms, I'd be interested to hear about them. >> >> >> I wouldn't have used the phrase "probably", if I knew for certain >> that >> any such idioms exist. > > I don't know for sure, but one guess would be code like this, > cout << "xxx" << f() << "yyy" << g() << "zzz" << h() << "\n"; > where the authors don't realize that the function calls can > happen in any order. If the functions really affect each other, this is *really* bad code. Why don't we require a diagnostic Warning: Terrible code - please rewrite! instad of having the compilers make it work anyway? Bo Persson --- [ comp.std.c++ is moderated. To submit articles, try just posting with ] [ your news-reader. If that fails, use mailto:std-c++@ncar.ucar.edu ] [ --- Please see the FAQ before posting. --- ] [ FAQ: http://www.jamesd.demon.co.uk/csc/faq.html ]