1、 Reference numberISO/IEC TR 24718:2005(E)ISO/IEC 2005 TECHNICAL REPORT ISO/IECTR24718First edition2005-02-15 Information technology Programming languages Guide for the use of the Ada Ravenscar Profile in high integrity systems Technologies de linformation Langages de programmation Guide pour lusage
2、de Ada Ravenscar Profile dans les systmes de haute intgrit ISO/IEC TR 24718:2005(E)PDF disclaimer This PDF file may contain embedded typefaces.In accordance with Adobes licensing policy,this file may be printed or viewed but shall not be edited unless the typefaces which are embedded are licensed to
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5、please inform the Central Secretariat at the address given below.ISO/IEC 2005 All rights reserved.Unless otherwise specified,no part of this publication may be reproduced or utilized in any form or by any means,electronic or mechanical,including photocopying and microfilm,without permission in writi
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7、 24718:2005(E)ISO/IEC 2005 All rights reserved iii Foreword ISO(the International Organization for Standardization)and IEC(the International Electrotechnical Commission)form the specialized system for worldwide standardization.National bodies that are members of ISO or IEC participate in the develop
8、ment of International Standards through technical committees established by the respective organization to deal with particular fields of technical activity.ISO and IEC technical committees collaborate in fields of mutual interest.Other international organizations,governmental and non-governmental,i
9、n liaison with ISO and IEC,also take part in the work.In the field of information technology,ISO and IEC have established a joint technical committee,ISO/IEC JTC 1.International Standards are drafted in accordance with the rules given in the ISO/IEC Directives,Part 2.The main task of the joint techn
10、ical committee is to prepare International Standards.Draft International Standards adopted by the joint technical committee are circulated to national bodies for voting.Publication as an International Standard requires approval by at least 75%of the national bodies casting a vote.In exceptional circ
11、umstances,the joint technical committee may propose the publication of a Technical Report of one of the following types:type 1,when the required support cannot be obtained for the publication of an International Standard,despite repeated efforts;type 2,when the subject is still under technical devel
12、opment or where for any other reason there is the future but not immediate possibility of an agreement on an International Standard;type 3,when the joint technical committee has collected data of a different kind from that which is normally published as an International Standard(“state of the art”,f
13、or example).Technical Reports of types 1 and 2 are subject to review within three years of publication,to decide whether they can be transformed into International Standards.Technical Reports of type 3 do not necessarily have to be reviewed until the data they provide are considered to be no longer
14、valid or useful.Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights.ISO and IEC shall not be held responsible for identifying any or all such patent rights.ISO/IEC TR 24718,which is a Technical Report of type 3,was prepared by the Univ
15、ersity of York for the British Standards Institution(BSI)as guidelines published in 2003,and was adopted(without modifications)by Joint Technical Committee ISO/IEC JTC 1,Information technology,Subcommittee SC 22,Programming languages,their environments and system software interfaces.ISO/IEC TR 24718
16、:2005(E)iv ISO/IEC 2005 All rights reserved Introduction The use of Ada has proven to be of great value within high integrity and real-time applications,albeit via language subsets of deterministic constructs,to ensure full analysability of the code.Such subsets have been defined for Ada 83,but these have excluded tasking on the grounds of its non-determinism and inefficiency.Advances in the area of schedulability analysis currently allow hard deadlines to be checked,even in the presence of a ru
