Index: README =================================================================== --- README (revision 6244dfb9b0062e49cf3bf4ca00c1139881b7972e) +++ README (revision be5aa1bdda2dce427692030b8a71558b7cec35cb) @@ -2,73 +2,81 @@ ====================================== -This is a PRE-RELEASE version of cfa-cc. It exists solely for the purpose of -private experimentation and scholarly research. The authors disclaim all -responsibility for the consequences of any malfunction of the software, -including the malfunction of any programs compiled using the software. +This is a PRE-RELEASE version of cfa-cc. It exists solely for the +purpose of private experimentation and scholarly research. The authors +disclaim all responsibility for the consequences of any malfunction of +the software, including the malfunction of any programs compiled using +the software. What is Cforall? ---------------- -Cforall is a language design extending ISO C. The purpose of the project is to -engineer modern language features into C in an evolutionary rather than -revolutionary way. Java is an example of the revolutionary approach of -modernizing C/C++, resulting in a new language rather than an extension of its -descendents. C++, Fortran 95 and Cobol 9X are examples of the evolutionary -approach where modern language features are added and problems fixed within the -framework of an existing language. +Cforall is a language design extending ISO C. The purpose of the +project is to engineer modern language features into C in an +evolutionary rather than revolutionary way. Java is an example of the +revolutionary approach of modernizing C/C++, resulting in a new +language rather than an extension of its descendents. C++, Fortran 95 +and Cobol 9X are examples of the evolutionary approach where modern +language features are added and problems fixed within the framework of +an existing language. -The goal of this project is to produce a largely backwards compatible version -of C containing many modern language features and fixing some of the well known -C problems. Without continued development of the language, C will be unable to -cope with the needs of modern programming problems and programmers; as a -result, it will fade into disuse. Considering the large body of existing C -code and programmers, there is a significant impetus to ensure C is transformed -into a modern programming language. +The goal of this project is to produce a largely backwards compatible +version of C containing many modern language features and fixing some +of the well known C problems. Without continued development of the +language, C will be unable to cope with the needs of modern programming +problems and programmers; as a result, it will fade into disuse. +Considering the large body of existing C code and programmers, there is +a significant impetus to ensure C is transformed into a modern +programming language. What is cfa-cc? --------------- -cfa-cc is a collection of programs centred around a translator that takes -Cforall code as input and outputs corresponding C code. This is complemented -by a compiler driver in the style of "gcc", which handles preprocessing, -compiling, assembling, and linking and invokes the translator at appropriate -moments. +cfa-cc is a collection of programs centred around a translator that +takes Cforall code as input and outputs corresponding C code. This +is complemented by a compiler driver in the style of "gcc", which +handles preprocessing, compiling, assembling, and linking and invokes +the translator at appropriate moments. What is required in order to use cfa-cc? ---------------------------------------- -Building cfa-cc requires GNU Make and gcc/g++ 4. cfa-cc is written in C++. +Building cfa-cc requires GNU Make and gcc/g++ 3. cfa-cc is written in +C++. -The compiler driver uses an installed version of gcc to handle all aspects of -the compilation process except for the Cforall->C translation. Currently, only -gcc 4.x is supported. +The compiler driver uses an installed version of gcc to handle all +aspects of the compilation process except for the Cforall->C translation. +Currently, only gcc 3.2 is supported. How is cfa-cc used? ------------------- -The compiler driver "cfa" accepts all of the arguments of gcc, and is used in -the same way. For example: +The compiler driver "cfa" accepts all of the arguments of gcc, and is +used in the same way. For example: cfa -c test.c cfa test.o -Cforall source files must end with '.c' in order to be compiled by the compiler -driver. In addition, the flag "-CFA" causes cfa to invoke the preprocessor and -translator and send the translator output to standard output. +Cforall source files must end with '.c' in order to be compiled by the +compiler driver. In addition, the flag "-CFA" causes cfa to invoke the +preprocessor and translator and send the translator output to standard +output. -It is possible to invoke the translator directly. The translator is installed -by default as /usr/local/lib/cfa-cpp. A typical invocation is: +In cases where the compiler driver is not useful (i.e., where gcc 3.2 +is not available), it is still possible to invoke the translator +directly. The translator is installed by default as +/usr/local/lib/cfa-cpp. A typical invocation is: /usr/local/lib/cfa-cpp -cp infile outfile -If outfile is omitted, output goes to standard output; if infile is also -omitted, input comes from standard input. Options to the translator other than -"-cp" will not produce valid C code and are only useful for debugging the -translator. +If outfile is omitted, output goes to standard output; if infile is +also omitted, input comes from standard input. Options to the +translator other than "-cp" will not produce valid C code and are only +useful for debugging the translator. How can C code be used with cfa-cc? ----------------------------------- -cfa-cc should be able to compile most ANSI C programs. It is also possible to -link against C libraries in most cases. Since Cforall supports overloading, -however, names used in Cforall code are mangled in the output C code. This -caused linker failures when the names refer to functions and objects in code -compiled with a standard C compiler. For this reason, it is necessary to -enclose the declarations of these functions and objects in extern "C" {} +cfa-cc should be able to compile most ANSI C programs. It is also +possible to link against C libraries in most cases. Since Cforall +supports overloading, however, names used in Cforall code are +mangled in the output C code. This will cause linker failures when +the names refer to functions and objects in code compiled with +a standard C compiler. For this reason, it is necessary to enclose +the declarations of these functions and objects in extern "C" {} blocks. For example: @@ -79,32 +87,38 @@ The extern "C" turns off name mangling for functions and objects declared -within the block. As a result, it is not possible to overload their names. +within the block. As a result, it is not possible to overload their +names. + +It is our intention to have a transparent solution to this problem +in place for our first official release. What's wrong with cfa-cc? ------------------------- +The authors consider this software to be in an unstable state. It is +quite likely that there are many reasonable programs that will fail +to compile. We encourage users to report their experiences to +cforall@plg.uwaterloo.ca, but we make no promises regarding support. -The authors consider this software to be in an unstable state. It is quite -likely that there are many reasonable programs that will fail to compile. We -encourage users to report their experiences to cforall@plg.uwaterloo.ca, but we -make no promises regarding support. +We have fixed most of the problems that we are aware of. There are +some exceptions: -We have fixed most of the problems that we are aware of. There are some -exceptions: + - initializers are poorly implemented; in particular, + file-scope initializers may result in the generation of invalid + C code -- initializers are poorly implemented; in particular, file-scope initializers - may result in the generation of invalid C code + - the ISO C99 designated initialization syntax '[n] = m' or + '.n = m' is not supported; use a colon in place of the equal sign + + - some legitimate programs will produce warnings from the C + compiler; these are harmless (in particular, the creation of + libcfa.a in the build process should cause four warnings from + gcc) -- the ISO C99 designated initialization syntax '[n] = m' or '.n = m' is not - supported; use a colon in place of the equal sign + - abstract types introduced using the keyword 'type' are not + implemented (although 'type' can be used to introduce type + parameters) -- some legitimate programs will produce warnings from the C compiler; these are - harmless (in particular, the creation of libcfa.a in the build process should - cause four warnings from gcc) - -- abstract types introduced using the keyword 'type' are not implemented - (although 'type' can be used to introduce type parameters) - -- the implicit coercion of structure types to the type of their first member is - not implemented + - the implicit coercion of structure types to the type of their + first member is not implemented Who is responsible for cfa-cc?