| 1 | cfa-cc: Cforall to C Trans-compiler | 
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| 2 | ====================================== | 
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| 3 |  | 
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| 4 | This is a PRE-RELEASE version of cfa-cc.  It exists solely for the purpose of | 
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| 5 | private experimentation and scholarly research.  The authors disclaim all | 
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| 6 | responsibility for the consequences of any malfunction of the software, | 
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| 7 | including the malfunction of any programs compiled using the software. | 
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| 8 |  | 
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| 9 |  | 
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| 10 | What is Cforall? | 
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| 11 | ---------------- | 
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| 12 | Cforall is a language design extending ISO C. The purpose of the project is to | 
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| 13 | engineer modern language features into C in an evolutionary rather than | 
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| 14 | revolutionary way. Java is an example of the revolutionary approach of | 
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| 15 | modernizing C/C++, resulting in a new language rather than an extension of its | 
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| 16 | descendents. C++, Fortran 95 and Cobol 9X are examples of the evolutionary | 
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| 17 | approach where modern language features are added and problems fixed within the | 
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| 18 | framework of an existing language. | 
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| 19 |  | 
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| 20 | The goal of this project is to produce a largely backwards compatible version | 
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| 21 | of C containing many modern language features and fixing some of the well known | 
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| 22 | C problems. Without continued development of the language, C will be unable to | 
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| 23 | cope with the needs of modern programming problems and programmers; as a | 
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| 24 | result, it will fade into disuse.  Considering the large body of existing C | 
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| 25 | code and programmers, there is a significant impetus to ensure C is transformed | 
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| 26 | into a modern programming language. | 
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| 27 |  | 
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| 28 |  | 
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| 29 | What is cfa-cc? | 
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| 30 | --------------- | 
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| 31 | cfa-cc is a collection of programs centred around a translator (trans-compiler) | 
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| 32 | that takes Cforall code as input and outputs augmented C code that implements | 
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| 33 | new features.  The translator is complemented by a compiler driver in the style | 
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| 34 | of "gcc", which handles preprocessing (including cfa-cc after cpp), compiling, | 
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| 35 | assembling, and linking. | 
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| 36 |  | 
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| 37 | cfa-cc is currently written in C++, but will be eventually rewritten in Cforall. | 
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| 38 |  | 
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| 39 |  | 
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| 40 | How to download and build cfa-cc? | 
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| 41 | ---------------------------------------- | 
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| 42 | Download cfa-cc using | 
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| 43 |  | 
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| 44 | $ git clone https://github.com/cforall/cforall.git | 
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| 45 |  | 
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| 46 | Read the ./INSTALL file for build instructions. | 
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| 47 |  | 
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| 48 |  | 
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| 49 | How to use cfa-cc? | 
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| 50 | ------------------- | 
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| 51 | The compiler driver "cfa" accepts all of the arguments for gcc, and is used in | 
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| 52 | the same way.  For example: | 
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| 53 |  | 
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| 54 | cfa -c test.c | 
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| 55 | cfa test.o | 
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| 56 |  | 
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| 57 | Cforall source files may end with '.c' or '.cfa' in order to be compiled by the | 
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| 58 | compiler driver.  In addition, the flag "-CFA" causes cfa to invoke the C | 
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| 59 | preprocessor and Cforall translator and write the translator output to standard | 
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| 60 | output. | 
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| 61 |  | 
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| 62 |  | 
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| 63 | How to use C code with cfa-cc? | 
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| 64 | ----------------------------------- | 
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| 65 | cfa-cc should be able to compile and link most ANSI C programs with associated | 
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| 66 | C standard libraries. | 
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| 67 |  | 
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| 68 | Like C++, Cforall supports overloading, resulting in duplicate names that are | 
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| 69 | disambiguated using name mangling in the translated C code.  To prevent | 
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| 70 | mangling of C names, it is necessary to wrap C declarations in an extern "C" | 
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| 71 | block, as for C++.  For example: | 
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| 72 |  | 
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| 73 | extern "C" { | 
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| 74 | #include <curses.h> | 
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| 75 | #include <getopt.h> | 
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| 76 | } | 
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| 77 |  | 
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| 78 | The extern "C" turns off name mangling for functions and objects declared | 
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| 79 | within the block. All C standard headers are pre-wrapped, so most wrapping is | 
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| 80 | unnecessary. | 
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| 81 |  | 
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| 82 |  | 
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| 83 | What's wrong with cfa-cc? | 
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| 84 | ------------------------- | 
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| 85 |  | 
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| 86 | The authors consider cfa-cc to be in a semi-stable state.  It is possible for | 
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| 87 | reasonable Cforall programs to fail compilation.  A list of bugs and fixes is | 
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| 88 | available here: https://cforall.uwaterloo.ca/trac.  We encourage users to | 
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| 89 | report their experiences to cforall@plg.uwaterloo.ca, but we can make no | 
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| 90 | promises regarding support. | 
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| 91 |  | 
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| 92 | Also, the Cforall features web-page https://cforall.uwaterloo.ca/features lists | 
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| 93 | small syntactic and semantic differences with standard C. | 
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| 94 |  | 
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| 95 |  | 
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| 96 | Who is responsible for cfa-cc? | 
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| 97 | ------------------------------ | 
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| 98 | Cforall was designed and implemented by Andrew Beach, Richard Bilson, Michael | 
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| 99 | Brooks, Peter A. Buhr, Thierry Delisle Glen Ditchfield, Rodolfo G. Esteves, | 
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| 100 | Aaron Moss, Colby Parsons, Rob Schluntz, Fangren Yu, Mubeen Zulfiqar, and others. | 
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| 101 |  | 
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| 102 | Check the Cforall web site https://cforall.uwaterloo.ca for news and updates. | 
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