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: 103376,4ffc4a297a9f10e0 X-Google-NewGroupId: yes X-Google-Attributes: gida07f3367d7,domainid0,public,usenet X-Google-Language: ENGLISH,UTF8 Path: g2news1.google.com!news4.google.com!feeder.news-service.com!94.75.214.39.MISMATCH!aioe.org!.POSTED!not-for-mail From: =?utf-8?Q?Yannick_Duch=C3=AAne_=28Hibou57?= =?utf-8?Q?=29?= Newsgroups: comp.lang.ada Subject: Re: Thoughts on AdaCore maintaining GCC-incompatible GNAT sources Date: Sun, 06 Feb 2011 20:58:48 +0100 Organization: Ada @ Home Message-ID: References: <62c8c6c1-6578-4e61-b68a-2c192f34aa94@f20g2000prn.googlegroups.com> <1456fbc5-f951-4721-8575-0b73a492f275@r29g2000yqj.googlegroups.com> <80886810-73e0-4eea-88e3-6653afc2f45b@a28g2000prb.googlegroups.com> <82k4hyq328.fsf@stephe-leake.org> NNTP-Posting-Host: 59xjXE7stDARAmb8zI1USw.user.speranza.aioe.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed; delsp=yes Content-Transfer-Encoding: Quoted-Printable X-Complaints-To: abuse@aioe.org User-Agent: Opera Mail/11.01 (Win32) X-Notice: Filtered by postfilter v. 0.8.2 Xref: g2news1.google.com comp.lang.ada:16901 Date: 2011-02-06T20:58:48+01:00 List-Id: Le Tue, 25 Jan 2011 02:29:17 +0100, Randy Brukardt = a =C3=A9crit: >> What do you mean by "the exact same setup" here ? Can you explain wit= h = >> an >> example ? > > I meant the same compiler, runtime libraries, tools, etc. > >> What would be amazing, would be valid sources not compiling (and most= of >> GNAT is written in Ada). That sound mysterious. > > "Ada" is an abstract notion. No compiler implements Ada exactly right,= = > and > I'm dubious that is even possible. There are literally billions on > combinations possible, and of course most of those combinations are > harmless. But there always are some that are not. > [...] > Moreover, bugs can extend beyond the source code. The problem I had wi= th = > the > Janus/Ada optimizer occurred because the code being optimized was too > simple! The code was so simple that the optimizer actually was making = it > bigger and that caused the buffer to overflow (since it doesn't know h= ow = > to > grow - it's not needed). This isn't the sort of effect that you could = = > notice > from normal testing -- you actually would have to try to compile packa= ges > with that sort of code (no test programs were large enough to expose t= he > problem). > > I'm sure GNAT has somewhat fewer of these issues, as their compiler ha= s = > more > users than Janus/Ada does, but that isn't likely to make it free of su= ch > issues, just a bit less likely to show them. > > Randy. So you just increased the quality of your implementation. That's a good.= At least this kind of language or implementation topics are workable and= = stands for goods (this also advocate for the use of more than just a = single unique compiler), while the troubles which come with different = build process, environment, available libraries, etc, are less fun (thes= e = ones are real nightmare). -- = Si les chats miaulent et font autant de vocalises bizarres, c=E2=80=99es= t pas pour = les chiens. =E2=80=9CI am fluent in ASCII=E2=80=9D [Warren 2010]