IAR Embedded Workbench® MISRA C:2004 Reference Guide EWMISRAC:2004-3 EWMISRAC:2004-3 COPYRIGHT NOTICE Copyright © 2004–2011 IAR Systems AB. No part of this document may be reproduced without the prior written consent of IAR Systems AB. The software described in this document is furnished under a license and may only be used or copied in accordance with the terms of such a license. DISCLAIMER The information in this document is subject to change without notice and does not represent a commitment on any part of IAR Systems. While the information contained herein is assumed to be accurate, IAR Systems assumes no responsibility for any errors or omissions. In no event shall IAR Systems, its employees, its contractors, or the authors of this document be liable for special, direct, indirect, or consequential damage, losses, costs, charges, claims, demands, claim for lost profits, fees, or expenses of any nature or kind. 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EDITION NOTICE Third edition: January 2011 Part number: EWMISRAC:2004-3 This guide describes version 1.0 of the IAR Systems implementation of The Motor Industry Software Reliability Association’s Guidelines for the Use of the C Language in Critical Systems (the MISRA-C:2004 standard), including the MISRA-C:2004 Technical Corrigendum 1, dated 17 July, 2007. Internal reference: IJOA EWMISRAC:2004-3 Contents Preface ...................................................................................................................... 5 Who should read this guide ................................................................. 5 What this guide contains ....................................................................... 5 Other documentation ............................................................................. 6 Document conventions .......................................................................... 6 Introduction .......................................................................................................... 9 Using MISRA C .......................................................................................... 9 Claiming compliance ........................................................................... 9 Implementation and interpretation of the MISRA C rules .... 9 Checking the rules .............................................................................. 10 Enabling MISRA C rules ....................................................................... 11 General IDE options ....................................................................................... 13 MISRA C 2004 ......................................................................................... 13 Compiler IDE options .................................................................................... 15 MISRA C 2004 ......................................................................................... 15 Command line options .................................................................................. 17 Options summary ................................................................................... 17 Descriptions of options ........................................................................ 17 MISRA C:2004 rules reference .................................................................. 19 Summary of rules .................................................................................. 19 Group 1: Environment ....................................................................... 19 Group 2: Language extensions ........................................................... 20 Group 3: Documentation .................................................................... 20 Group 4: Character sets ...................................................................... 20 Group 5: Identifiers ............................................................................ 21 Group 6: Types ................................................................................... 21 Group 7: Constants ............................................................................. 21 Group 8: Declarations and definitions ............................................... 22 3 EWMISRAC:2004-3 Group 9: Initialization ........................................................................ 23 Group 10: Arithmetic type conversions ............................................. 23 Group 11: Pointer type conversions ................................................... 24 Group 12: Expressions ....................................................................... 24 Group 13: Control statement expressions .......................................... 25 Group 14: Control flow ...................................................................... 26 Group 15: Switch statements ............................................................. 27 Group 16: Functions ........................................................................... 27 Group 17: Pointers and arrays ............................................................ 28 Group 18: Structures and unions ........................................................ 28 Group 19: Preprocessing directives ................................................... 29 Group 20: Standard libraries .............................................................. 30 Group 21: Runtime failures ................................................................ 31 Environment rules .................................................................................. 31 Language extensions ............................................................................. 32 Documentation ........................................................................................ 33 Character sets .......................................................................................... 35 Identifiers ................................................................................................... 36 Types ............................................................................................................ 37 Constants ................................................................................................... 39 Declarations and definitions .............................................................. 39 Initialization .............................................................................................. 42 Arithmetic type conversions ............................................................. 43 Pointer type conversions ..................................................................... 46 Expressions ................................................................................................ 47 Control statement expressions ........................................................ 51 Control flow .............................................................................................. 53 Switch statements .................................................................................. 56 Functions .................................................................................................... 57 Pointers and arrays ................................................................................ 60 Structures and unions ........................................................................... 61 Preprocessing directives ...................................................................... 62 Standard libraries ................................................................................... 67 Runtime failures ...................................................................................... 69 IAR Embedded Workbench® MISRA C:2004 4 Reference Guide EWMISRAC:2004-3 Preface Welcome to the IAR Embedded Workbench® MISRA C:2004 Reference Guide. This guide includes gives reference information about the IAR Systems implementation of The Motor Industry Software Reliability Association’s Guidelines for the Use of the C Language in Critical Systems. Who should read this guide You should read this guide if you are developing a software product using the MISRA-C:2004 rules. In addition, you should have a working knowledge of: ● The C programming language ● The MISRA C subset of the C language ● Application development for safety-critical embedded systems ● The architecture and instruction set of your microcontroller (refer to the chip manufacturer's documentation) ● The operating system of your host machine. What this guide contains Below is a brief outline and summary of the chapters in this guide. ● Introduction explains the benefits of using MISRA C and gives an overview of the IAR Systems implementation. ● General IDE options describes the general MISRA C options in the IAR Embedded Workbench IDE. ● Compiler IDE options describes the MISRA C compiler options in the IAR Embedded Workbench IDE. ● Command line options explains how to set the options from the command line. ● MISRA C:2004 rules reference describes