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: 103376,45a9122ddf5fcf5 X-Google-Attributes: gid103376,public From: kst@thomsoft.com (Keith Thompson) Subject: Re: Valid Attribute and Unchecked Conversion Date: 1996/10/06 Message-ID: #1/1 X-Deja-AN: 187230290 sender: news@thomsoft.com (USENET News Admin @flash) x-nntp-posting-host: pulsar references: <3252ED6B.1B74@lmco.com> <53151i$ddd@newsbf02.news.aol.com> organization: Thomson Software Products, San Diego, CA, USA newsgroups: comp.lang.ada originator: kst@pulsar Date: 1996-10-06T00:00:00+00:00 List-Id: In dewar@schonberg.cs.nyu.edu (Robert Dewar) writes: [...] > Indeed the Ada 95 section on unchecked conversion (section 13.9) does not > mention the word erroneous at all, so an unchecked conversoin BY ITS SELF > never makes a program execution erroneous in Ada 95. But RM95-13.9.1(12) says: A call to an imported function or an instance of Unchecked_Conversion is erroneous if the result is scalar, and the result object has an invalid representation. Probably that paragraph should have been in 13.9 rather than 13.9.1. Note that there are several paragraphs after this in the AARM encouraging implementations to behave sensibly: [...] We considered requiring such sensible behavior, but it resulted in too much arcane verbiage, and since implementations have little incentive to behave irrationally, such verbiage is not important to have. So implementations are encouraged to implement sensibly something that users are encouraged to avoid. -- Keith Thompson (The_Other_Keith) kst@thomsoft.com <*> TeleSoft^H^H^H^H^H^H^H^H Alsys^H^H^H^H^H Thomson Software Products 10251 Vista Sorrento Parkway, Suite 300, San Diego, CA, USA, 92121-2706 FIJAGDWOL