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-Thread: 103376,28a755ada641b984 X-Google-Attributes: gid103376,public X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news1.google.com!news1.google.com!news.glorb.com!border1.nntp.dca.giganews.com!border2.nntp.dca.giganews.com!nntp.giganews.com!wn14feed!worldnet.att.net!attbi_s03.POSTED!53ab2750!not-for-mail From: "Jeff C," Newsgroups: comp.lang.ada References: <%7XQc.100722$eM2.38916@attbi_s51> Subject: Re: Longstanding GNAT bug, bad code, or both -- Answer..Bad code. X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2800.1437 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1441 Message-ID: NNTP-Posting-Host: 24.147.74.171 X-Complaints-To: abuse@comcast.net X-Trace: attbi_s03 1091887633 24.147.74.171 (Sat, 07 Aug 2004 14:07:13 GMT) NNTP-Posting-Date: Sat, 07 Aug 2004 14:07:13 GMT Organization: Comcast Online Date: Sat, 07 Aug 2004 14:07:14 GMT Xref: g2news1.google.com comp.lang.ada:2617 Date: 2004-08-07T14:07:14+00:00 List-Id: Ok. I submitted a bugzilla report and it has already been cancelled. Apparently, declaring a variable as aliased makes it contrained. (According to one of the gcc Ada maintainers) I did spend a little time looking through the LRM for this but obviously not enough. It seemed a little counter-intutitive since one might think that given an aliased variable one would have to really worry about the discriminant changing all the time, so why was the compiler surprised when it did.......After thinking about it, it is probably why the rule was created since I suppose otherwise the alias detection/contraint checking would get pretty hard and potentially computationally expensive at run time... Of course I could be wrong about why the rule is what it is...but I am willing to believe it.