High Integrity C++ Version
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
By Kumari Priyadarshani 22-04-2020 BBM 3Rd Year Variables in C a Variable Is a Name of the Memory Location. It Is Used to Store Data
By Kumari priyadarshani 22-04-2020 BBM 3rd year Variables in C A variable is a name of the memory location. It is used to store data. Its value can be changed, and it can be reused many times. It is a way to represent memory location through symbol so that it can be easily identified. Let's see the syntax to declare a variable: type variable_list; The example of declaring the variable is given below: int a; float b; char c; Here, a, b, c are variables. The int, float, char are the data types. We can also provide values while declaring the variables as given below: int a=10,b=20;//declaring 2 variable of integer type float f=20.8; char c='A'; Rules for defining variables A variable can have alphabets, digits, and underscore. A variable name can start with the alphabet, and underscore only. It can't start with a digit. No whitespace is allowed within the variable name. A variable name must not be any reserved word or keyword, e.g. int, float, etc. Valid variable names: int a; int _ab; int a30; Invalid variable names: int 2; int a b; int long; Types of Variables in C There are many types of variables in c: local variable global variable static variable automatic variable external variable 1)Local Variable A variable that is declared inside the function or block is called a local variable. It must be declared at the start of the block. void function1(){ int x=10;//local variable } You must have to initialize the local variable before it is used. -
An Empirical Study Into COBOL Type Inferencing*
Science of Computer Programming ELSEVIERI Science of Computer Programming 40 (2001) 189-211 www.elsevier.nl/locate/scico An empirical study into COBOL type inferencing* Arie van Deursen 1, Leon Moonen 1 * CWL P. 0. Box 94079, 1090 GB Amsterdam, Netherlands Accepted 2 February 2001 Abstract In a typical COBOL program, the data division consists of 50% of the lines of code. Automatic type inference can help to understand the large collections of variable declarations contained therein, showing how variables are related based on their actual usage. The most problematic aspect of type inference is pollution, the phenomenon that types become too large, and contain variables that intuitively should not belong to the same type. The aim of the paper is to provide empirical evidence for the hypothesis that the use of subtyping is an effective way for dealing with pollution. The main results include a tool set to carry out type inference experiments, a suite of metrics characterizing type inference outcomes, and the experimental observation that only one instance of pollution occurs in the case study conducted. @ 2001 Elsevier Science B.V. All rights reserved. Keywords: Software maintenance; Static program analysis; Variable usage; Case study 1. Introduction In this paper, we will be concerned with the variables occurring in a COBOL pro gram. The two main parts of a COBOL program are the data division, containing declarations for all variables used, and the procedure division, which contains the state ments performing the program's functionality. Since it is in the procedure division that the actual computations are made, one would expect this division to be larger than the data division. -
Thriving in a Crowded and Changing World: C++ 2006–2020
Thriving in a Crowded and Changing World: C++ 2006–2020 BJARNE STROUSTRUP, Morgan Stanley and Columbia University, USA Shepherd: Yannis Smaragdakis, University of Athens, Greece By 2006, C++ had been in widespread industrial use for 20 years. It contained parts that had survived unchanged since introduced into C in the early 1970s as well as features that were novel in the early 2000s. From 2006 to 2020, the C++ developer community grew from about 3 million to about 4.5 million. It was a period where new programming models emerged, hardware architectures evolved, new application domains gained massive importance, and quite a few well-financed and professionally marketed languages fought for dominance. How did C++ ś an older language without serious commercial backing ś manage to thrive in the face of all that? This paper focuses on the major changes to the ISO C++ standard for the 2011, 2014, 2017, and 2020 revisions. The standard library is about 3/4 of the C++20 standard, but this paper’s primary focus is on language features and the programming techniques they support. The paper contains long lists of features documenting the growth of C++. Significant technical points are discussed and illustrated with short code fragments. In addition, it presents some failed proposals and the discussions that led to their failure. It offers a perspective on the bewildering flow of facts and features across the years. The emphasis is on the ideas, people, and processes that shaped the language. Themes include efforts to preserve the essence of C++ through evolutionary changes, to simplify itsuse,to improve support for generic programming, to better support compile-time programming, to extend support for concurrency and parallel programming, and to maintain stable support for decades’ old code. -
Defining the Undefinedness of C
Technical Report: Defining the Undefinedness of C Chucky Ellison Grigore Ros, u University of Illinois {celliso2,grosu}@illinois.edu Abstract naturally capture undefined behavior simply by exclusion, be- This paper investigates undefined behavior in C and offers cause of the complexity of undefined behavior, it takes active a few simple techniques for operationally specifying such work to avoid giving many undefined programs semantics. behavior formally. A semantics-based undefinedness checker In addition, capturing the undefined behavior is at least as for C is developed using these techniques, as well as a test important as capturing the defined behavior, as it represents suite of undefined programs. The tool is evaluated against a source of many subtle program bugs. While a semantics other popular analysis tools, using the new test suite in of defined programs can be used to prove their behavioral addition to a third-party test suite. The semantics-based tool correctness, any results are contingent upon programs actu- performs at least as well or better than the other tools tested. ally being defined—it takes a semantics capturing undefined behavior to decide whether this is the case. 1. Introduction C, together with C++, is the king of undefined behavior—C has over 200 explicitly undefined categories of behavior, and A programming language specification or semantics has dual more that are left implicitly undefined [11]. Many of these duty: to describe the behavior of correct programs and to behaviors can not be detected statically, and as we show later identify incorrect programs. The process of identifying incor- (Section 2.6), detecting them is actually undecidable even rect programs can also be seen as describing which programs dynamically. -
XL C/C++: Language Reference About This Document
IBM XL C/C++ for Linux, V16.1.1 IBM Language Reference Version 16.1.1 SC27-8045-01 IBM XL C/C++ for Linux, V16.1.1 IBM Language Reference Version 16.1.1 SC27-8045-01 Note Before using this information and the product it supports, read the information in “Notices” on page 63. First edition This edition applies to IBM XL C/C++ for Linux, V16.1.1 (Program 5765-J13, 5725-C73) and to all subsequent releases and modifications until otherwise indicated in new editions. Make sure you are using the correct edition for the level of the product. © Copyright IBM Corporation 1998, 2018. US Government Users Restricted Rights – Use, duplication or disclosure restricted by GSA ADP Schedule Contract with IBM Corp. Contents About this document ......... v Chapter 4. IBM extension features ... 11 Who should read this document........ v IBM extension features for both C and C++.... 11 How to use this document.......... v General IBM extensions ......... 11 How this document is organized ....... v Extensions for GNU C compatibility ..... 15 Conventions .............. v Extensions for vector processing support ... 47 Related information ........... viii IBM extension features for C only ....... 56 Available help information ........ ix Extensions for GNU C compatibility ..... 56 Standards and specifications ........ x Extensions for vector processing support ... 58 Technical support ............ xi IBM extension features for C++ only ...... 59 How to send your comments ........ xi Extensions for C99 compatibility ...... 59 Extensions for C11 compatibility ...... 59 Chapter 1. Standards and specifications 1 Extensions for GNU C++ compatibility .... 60 Chapter 2. Language levels and Notices .............. 63 language extensions ......... 3 Trademarks ............. -
Language Reference
Enterprise PL/I for z/OS Version 5 Release 3 Language Reference IBM SC27-8940-02 Note Before using this information and the product it supports, be sure to read the general information under “Notices” on page 613. Third Edition (September 2019) This edition applies to Enterprise PL/I for z/OS Version 5 Release 3 (5655-PL5), and IBM Developer for z/OS PL/I for Windows (former Rational Developer for System z PL/I for Windows), Version 9.1, and to any subsequent releases of any of these products until otherwise indicated in new editions or technical newsletters. Make sure you are using the correct edition for the level of the product. Order publications through your IBM® representative or the IBM branch office serving your locality. Publications are not stocked at the address below. A form for readers' comments is provided at the back of this publication. If the form has been removed, address your comments to: IBM Corporation, Department H150/090 555 Bailey Ave. San Jose, CA, 95141-1099 United States of America When you send information to IBM, you grant IBM a nonexclusive right to use or distribute the information in any way it believes appropriate without incurring any obligation to you. Because IBM Enterprise PL/I for z/OS supports the continuous delivery (CD) model and publications are updated to document the features delivered under the CD model, it is a good idea to check for updates once every three months. © Copyright International Business Machines Corporation 1999, 2019. US Government Users Restricted Rights – Use, duplication or disclosure restricted by GSA ADP Schedule Contract with IBM Corp. -
Automatic Detection of Unspecified Expression Evaluation in Freertos Programs
IT 14 022 Examensarbete 30 hp Juni 2014 Automatic Detection of Unspecified Expression Evaluation in FreeRTOS Programs Shahrzad Khodayari Institutionen för informationsteknologi Department of Information Technology . ... ... .... . . .. . . Acknowledgements This is a master thesis submitted in Embedded Systems to Department of Information Technology, Uppsala University, Uppsala, Sweden. I would like to express my deepest gratitude to my suppervisor Philipp Rümmer, Programme Director for Master’s programme in Embedded System at Uppsala University, for his patience in supporting continuously and generously guiding me with this project. I would like to appriciate professor Bengt Jonsson for reviewing my master thesis and offering valuable suggestions and comments. I would like to thank professor Daniel Kroening for helping me and providing updates of CBMC. Sincere thanks to my husband and my incredible parents who gave me courage and support throughout the project. Contents 1 Introduction..........................................................................................................1 Contributions.................................................................................................................3 Structure of the thesis report..........................................................................................3 2 Background...........................................................................................................5 2.1 Verification..............................................................................................................5 -
Fundamentals of Programming Session 12
Fundamentals of Programming Session 12 Instructor: Maryam Asadi Email: [email protected] 1 Fall 2018 These slides have been created using Deitel’s slides Sharif University of Technology Outlines Random Number Generation … Storage Classes Scope Rules 2 Random Number Generation … The values produced directly by rand are always in the range: 0 rand() RAND_MAX As you know, the following statement simulates rolling a six- sided die: face = 1 + rand() % 6; This statement always assigns an integer value (at random) to the variable face in the range 1 face 6. The width of this range (i.e., the number of consecutive integers in the range) is 6 and the starting number in the range is 1. 3 Random Number Generation … Referring to the preceding statement, we see that the width of the range is determined by the number used to scale rand with the remainder operator (i.e., 6), and the starting number of the range is equal to the number (i.e., 1) that is added to rand % 6. We can generalize this result as follows n = a + rand() % b; where a is the shifting value (which is equal to the first number in the desired range of consecutive integers) and b is the scaling factor (which is equal to the width of the desired range of consecutive integers). 4 Random Number Generation … 5 Random Number Generation … 6 Random Number Generation … Notice that a different sequence of random numbers is obtained each time the program is run, provided that a different seed is supplied. To randomize without entering a seed each time, use a statement like srand( time( NULL ) ); This causes the computer to read its clock to obtain the value for the seed automatically. -
PRU Optimizing C/C++ Compiler User's Guide
PRU Optimizing C/C++ Compiler v2.3 User's Guide Literature Number: SPRUHV7C July 2014–Revised July 2018 Contents Preface ........................................................................................................................................ 8 1 Introduction to the Software Development Tools.................................................................... 11 1.1 Software Development Tools Overview ................................................................................. 12 1.2 Compiler Interface.......................................................................................................... 13 1.3 ANSI/ISO Standard ........................................................................................................ 14 1.4 Output Files ................................................................................................................. 14 1.5 Utilities ....................................................................................................................... 14 2 Using the C/C++ Compiler ................................................................................................... 15 2.1 About the Compiler......................................................................................................... 16 2.2 Invoking the C/C++ Compiler ............................................................................................. 16 2.3 Changing the Compiler's Behavior with Options ....................................................................... 17 2.3.1 Linker -
Lecture 14 07/02/03
EE314 Spring 2003 Summer 2003 Lecture 14 07/02/03 LAB 6 Lab 6 involves interfacing to the IBM PC parallel port. Use the material on www.beyondlogic.org for reference. This lab requires the use of a Digilab board. Everyone should have one, but at least each group working together needs to have a board. Parallel Port Registers Address: Base + 0 => Data Port Base + 1 => Status Port Base + 2 => Control Port Status port bits: Signal Name Pin # Inverted Bit 7 Busy 11 Yes Bit 6 Ack 10 Bit 5 Paper Out 12 Bit 4 Select In 13 Bit 3 Error 15 Bit 2 IRQ N/A Bit 1 Reserved Bit 0 Reserved EE314 Spring 2003 Control Port Bits Signal Name Pin # Inverted Bit 7 Unused Bit 6 Unused Bit 5 Enable bi-directional port N/A Bit 4 Enable IRQ via ACK line N/A Bit 3 Select Printer 17 Yes Bit 2 Initialize Printer (Reset) 16 No Bit 1 Auto Linefeed 14 Yes Bit 0 Strobe 1 Yes Digilab Board Initialization: A program will be provided on the lab machines that is used to initialize the Digilab boards. It is called cfglab6.exe, and will be placed in a directory on the path, so that it can be executed simply by typing its name anywhere from a DOS prompt. C Programming Language Semantics Parameter passing to procedures: C is ‘call by value’ for scalar variables, ‘call by reference’ for vector variables. ‘Call by value’ means that the value of the parameter is pushed onto the stack and passed to the procedure as the parameter. -
Automatic Transformation of Iterative Loops Into Recursive Methods$ (Extended Version)
Automatic Transformation of Iterative Loops into Recursive MethodsI (extended version) David Insa, Josep Silva∗ Departament de Sistemes Inform`aticsi Computaci´o Universitat Polit`ecnica de Val`encia Camino de Vera s/n E-46022 Valencia, Spain. Abstract Context: In software engineering, taking a good election between recursion and iteration is essential because their efficiency and maintenance are different. In fact, developers often need to transform iteration into recursion (e.g., in debugging, to decompose the call graph into iterations); thus, it is quite surprising that there does not exist a public transformation from loops to recursion that can be used in industrial projects (i.e., it is automatic, it handles all kinds of loops, it considers exceptions, etc.). Objective: This article describes an industrial algorithm implemented as a Java library able to automatically transform iterative loops into equivalent recursive methods. The transformation is described for the programming language Java, but it is general enough as to be adapted to many other languages that allow iteration and recursion. Method: We describe the changes needed to transform loops of types while/do/for/foreach into recursion. We provide a transformation schema for each kind of loop. Results: Our algorithm is the first public transformation that can be used in industrial projects and faces the whole Java language (i.e., it is fully automatic, it handles all kinds of loops, it considers exceptions, it treats the control statements break and continue, it handles loop labels, it is able to transform any number of nested loops, etc.). This is particularly interesting because some of these features are missing in all previous work, probably, due to the complexity that their mixture introduce in the transformation. -
C for Java Programmers
C for Java Programmers George Ferguson Summer 2016 (Updated Summer 2021) 2 Contents 1 Introduction7 2 Overview of Java and C9 2.1 What’s The Same?.........................9 2.2 What’s Different?.......................... 10 3 Development and Execution 11 3.1 Development and Execution in Java and C............. 11 3.2 Setting Up Your Development Environment............ 14 3.3 Writing Your First C Program................... 16 3.4 Compiling Your First C Program.................. 17 4 Basic Expressions and Statements 21 4.1 Comments.............................. 21 4.2 Primitive Types........................... 22 4.3 Producing Output.......................... 23 4.4 Operators and Expressions..................... 24 4.5 Variables and Assigment...................... 26 4.6 Arrays................................ 27 4.7 Strings................................ 29 3 4 CONTENTS 5 Control Flow 31 5.1 Conditional Statements....................... 31 5.2 Iteration Statements......................... 32 5.3 Other Control Flow Statements................... 33 6 Functions 35 6.1 Function Parameters and Arguments................ 36 6.2 Function Declarations........................ 37 7 Structured Types 39 8 Memory Management 43 8.1 Variables, Addresses, and Pointers................. 43 8.2 Passing Arguments by Reference.................. 46 8.3 Memory Allocation......................... 48 8.4 Dynamic Memory Allocation in Java................ 49 8.5 Dynamic Memory Allocation in C................. 50 8.6 Dynamic Arrays........................... 54 8.7 Dynamic Data Structures...................... 56 8.8 Function Pointers.......................... 64 9 Defining New Types 69 10 Sharing Code: Files and Libraries 73 10.1 The C Preprocessor......................... 73 10.2 Separate Compilation, Libraries, and Linking........... 75 10.3 Standard System Libraries..................... 76 CONTENTS 5 10.4 Project Development........................ 77 10.5 Building Larger C Programs.................... 79 11 Debugging a C Program 83 11.1 Debuggers.............................