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=-0.8 required=5.0 tests=BAYES_00,INVALID_DATE autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,ff4487ffe32cc5a4 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 1994-09-24 04:46:07 PST Path: bga.com!news.sprintlink.net!pipex!lyra.csx.cam.ac.uk!doc.ic.ac.uk!yama.mcc.ac.uk!cs.man.ac.uk!newshost!bevan From: bevan@cs.man.ac.uk (Stephen J Bevan) Newsgroups: comp.lang.ada Subject: Re: Package Interface, and interoperbility Date: 24 Sep 1994 10:44:12 GMT Organization: Department of Computer Science; University of Manchester Message-ID: References: NNTP-Posting-Host: lemur.cs.man.ac.uk In-reply-to: WOODRUFF@ec2226.addvax.llnl.gov's message of 23 Sep 94 15:53:16 Date: 1994-09-24T10:44:12+00:00 List-Id: In article WOODRUFF@ec2226.addvax.llnl.gov writes: ... My concern is that this appears to assume that *every* C implementation uses the same representation for Element *. Otherwise I think some C-compiled library will not be callable from my Ada program because the C compiler used a representation for Element * that disagrees with the Ada compiler's code. What's worse, one library will be fine and another (compiled with a different C compiler) will be unusable, and I won't know before I spend MY OWN MONEY (tm) on the library that I'm in trouble. The problem you describe is possible, but doesn't seem to happen in practice. "the market" appears to have ensured that every (commercial) C implementation (on a given platform) does use the same representation. If the compiler didn't, it wouldn't be able to link against third party libraries and hence people probably wouldn't buy the compiler unless there was a great incentive to do so.