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=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,cef1e23795181e0c X-Google-Attributes: gid103376,public From: dewar@gnat.com Subject: Re: Alternate to Unchecked_Conversion - Portable? Date: 1999/03/01 Message-ID: <7bei3a$pjk$1@nnrp1.dejanews.com>#1/1 X-Deja-AN: 450004089 References: <36d05e39.0@news.pacifier.com> <36d2638e.6427631@nntp.concentric.net> <7avpi0$jke$1@nnrp1.dejanews.com> <36d3ba85.713118@nntp.concentric.net> <7b2l6s$vu3$1@nnrp1.dejanews.com> <36d50d18.695962@nntp.concentric.net> <7b3glh$ml6$1@nnrp1.dejanews.com> <7b49m5$eet$1@nnrp1.dejanews.com> <36d65c7c.15971534@nntp.concentric.net> <7b5tr0$rso$1@nnrp1.dejanews.com> <36d79e94.11378508@nntp.concentric.net> <7be1ot$mjg$1@plug.news.pipex.net> X-Http-Proxy: 1.0 x13.dejanews.com:80 (Squid/1.1.22) for client 166.72.81.240 Organization: Deja News - The Leader in Internet Discussion X-Article-Creation-Date: Mon Mar 01 17:17:40 1999 GMT Newsgroups: comp.lang.ada X-Http-User-Agent: Mozilla/4.04 [en] (OS/2; I) Date: 1999-03-01T00:00:00+00:00 List-Id: In article <7be1ot$mjg$1@plug.news.pipex.net>, "Nick Roberts" wrote: > But, we (programmers in the real world) also need to do > what we can to punish compiler makers whose products: (a) > fail to conform to the standard; > (b) conform, but in a way that is likely to create > portability difficulties (without good excuse). Even if > this is just in the form of disrecommendation to clients > (I am a consultant) or colleagues, we need to stand > shoulder-to-shoulder. It's not so simple. Conformance to the standard is a desirable property, but not the only desirable property, and a compiler vendor who considers conformance to be of primary importance over all other considerations may well produce a very correct compiler that is not however usable for any number of reasons (just remember that Ada/Ed was fully conformant :-) To take a simple example, an x86 compiler that does not support 80-bit IEEE extended arithmetic is clearly violates B.2(10): 10 Floating point types corresponding to each floating point format fully supported by the hardware. and is thus non-conformant. It will still be fully validatable, since this is not the sort of thing the validation can test with automated tests. Does that mean the compiler is unusable, or we should recommend that people not use it? Seems an extreme viewpoint to me. If your application does not need 80-bit float (or perhaps even does not want it, since it wants to be completely portable), then this omission may be completely unimportant. Robert Dewar Ada Core Technologies P.S. Just to ensure that people do not regard the above as special pleading for non-conformances in GNAT, please be sure to realize that GNAT *does* support 80-bit float on the ia32 (x86). -----------== Posted via Deja News, The Discussion Network ==---------- http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own