diff --git a/2001/bellard/README.md b/2001/bellard/README.md index 882040106..a8b2ad611 100644 --- a/2001/bellard/README.md +++ b/2001/bellard/README.md @@ -1,11 +1,10 @@ # Best abuse of the rules - Fabrice Bellard - 451 chemin du mas de Matour - 34790 GRABELS - France - - http://bellard.org +Fabrice Bellard +451 chemin du mas de Matour +34790 Grabels +France +https://bellard.org ## To build: @@ -27,7 +26,11 @@ format so that will also make it harder to work. As it is it segfaults. He fixed an earlier segfault so that at least the file can be opened and he also changed some of the macro uses to what they expanded to but mostly he kept it the same. He also fixed `bellard.otccex.c` so it does not segfault and seemingly works -okay. Thank you Cody for your assistance! +okay (it did not work at all). The author stated that they used [gcc +2.95.2](https://ftp.gnu.org/gnu/gcc/gcc-2.95.2/gcc-everything-2.95.2.tar.gz) but +we don't know if that's relevant or not. Thank you Cody for your assistance! Can +you fix the entry? We welcome your help! If you can please look at +[bugs.md](/bugs.md) for more information. Thank you! ## Try: @@ -42,125 +45,131 @@ okay. Thank you Cody for your assistance! ## Author's remarks: - OTCC is an Obfuscated Tiny C Compiler for i386-linux. It generates - FAST! i386 32 bit code (no bytecode) and it is powerful enough to - compile itself. OTCC supports a strict subset of C. This subset is - compilable by a standard ANSI C compiler. OTCC compiles, - assembles, links and runs C code without the need of any other - program. +`OTCC` is an Obfuscated Tiny C Compiler for i386-linux. It generates +FAST! i386 32 bit code (no bytecode) and it is powerful enough to +compile itself. `OTCC` supports a strict subset of C. This subset is +compilable by a standard ANSI C compiler. `OTCC` compiles, +assembles, links and runs C code without the need of any other +program. - You can use it by typing: +You can use it by typing: - ./bellard bellard.c [args]... +```sh +./bellard bellard.c [args]... +``` - or by giving the C source to its standard input. +or by giving the C source to its standard input. - 'args' are given to the 'main' function of bellard.c (argv[0] is - bellard.c). +`args` are given to the `main` function of `bellard.c` (`argv[0]` is +[bellard.c](bellard.c)). - Examples: +### Examples: - - Sample compilation and execution: +- Sample compilation and execution: +```sh ./bellard bellard.otccex.c 10 +``` - - Self compilation: +- Self compilation: +```sh ./bellard bellard.c bellard.otccex.c 10 +``` - - Self compilation iterated... +- Self compilation iterated... +```sh ./bellard bellard.c bellard.c bellard.otccex.c 10 - +``` An alternate syntax is to use it as a script interpreter: you can - put '#!/usr/local/bin/otcc' at the beginning of your C source if - you installed otcc at this place. + put `#!/usr/local/bin/otcc` at the beginning of your C source if + you installed `otcc` at this place. - Supported C language subset (read joint example 'otccex.c' to have - an introduction to OTCC dialect): +### Supported C language subset (read joint example [bellard.otccex.c](bellard.otccex.c) to have an introduction to `OTCC` dialect) - - Expressions: +#### Expressions: - * binary operators, by decreasing priority order: '*' '/' '%', - '+' '-', '>>' '<<', '<' '<=' '>' '>=', '==' '!=', '&', - '^', '|', '=', '&&', '||'. +* binary operators, by decreasing priority order: `*` `/` `%`, + `+` `-`, `>>` `<<`, `<` `<=` `>` `>=`, `==` `!=`, `&`, + `^`, `|`, `=`, `&&`, `||`. - * '&&' and '||' have the same semantics as C : left to right - evaluation and early exit. +* `&&` and `||` have the same semantics as in C: left to right + evaluation and early exit. - * Parenthesis are supported. +* Parenthesis are supported. - * Unary operators: '&', '*' (pointer indirection), '-' - (negation), '+', '!', '~', post fixed '++' and '--'. +* Unary operators: `&`, `*` (pointer indirection), `-` + (negation), `+`, `!`, `~`, post fixed `++` and `--`. - * Pointer indirection ('*') only works with explicit cast to - 'char *', 'int *' or 'int (*)()' (function pointer). +* Pointer indirection (`*`) only works with explicit cast to + `char *`, `int *` or `int (*)()` (function pointer). - * '++', '--', and unary '&' can only be used with variable - lvalue (left value). +* `++`, `--`, and unary `&` can only be used with variable + lvalue (left value). - * '=' can only be used with variable or '*' (pointer - indirection) lvalue. +* `=` can only be used with variable or `*` (pointer + indirection) lvalue. - * Function calls are supported with standard i386 calling - convention. Function pointers are supported with explicit - cast. Functions can be used before being declared. +* Function calls are supported _with standard **i386** calling + convention_. Function pointers are supported _with explicit + cast_. Functions can be used before being declared. - - Types: only signed integer ('int') variables and functions can - be declared. Variables cannot be initialized in - declarations. Only old K&R function declarations are parsed - (implicit integer return value and no types on arguments). +- Types: only signed integer (`int`) variables and functions can + be declared. Variables cannot be initialized in + declarations. _Only old K&R function declarations are parsed + (implicit integer return value and no types on arguments)_. - - Any function or variable from the libc can be used because OTCC - uses the libc dynamic linker to resolve undefined symbols. +- Any function or variable from the libc can be used because `OTCC` + uses the libc dynamic linker to resolve undefined symbols. - - Instructions: blocks ('{' '}') are supported as in C. 'if' and - 'else' can be used for tests. The 'while' and 'for' C constructs - are supported for loops. 'break' can be used to exit - loops. 'return' is used for the return value of a function. +- Instructions: blocks (`{` `}`) are supported as in C. `if` and + `else` can be used for tests. The `while` and `for` C looks are supported. + `break` can be used to exit loops. `return` is used for the return value of a + function. - - Identifiers are parsed the same way as C. Local variables are - handled, but there is no local name space (not a problem if - different names are used for local and global variables). +- Identifiers are parsed the same way as C. Local variables are + handled, but there is no local name space (not a problem if + different names are used for local and global variables). - - Numbers can be entered in decimal, hexadecimal ('0x' or '0X' - prefix), or octal ('0' prefix). +- Numbers can be entered in decimal, hexadecimal (`0x` or `0X` + prefix), or octal (`0` prefix). - - '#define' is supported without function like arguments. No macro - recursion is tolerated. Other preprocessor directives are - ignored. +- `#define` is supported without function like arguments. _No macro + recursion is tolerated_; _other preprocessor directives are + ignored_. - - C Strings and C character constants are supported. Only '\n', - '\"', '\'' and '\\' escapes are recognized. +- C Strings and C character constants are supported. Only `\n`, + `\"`, `\'` and `\\` escapes are recognized. - - C Comments can be used (but no C++ comments). +- C Comments can be used (but no C++ comments). - - No error is displayed if an incorrect program is given. +- No error is displayed if an incorrect program is given. - - Memory: the code, data, and symbol sizes are limited to 100KB - (it can be changed in the source code). +- Memory: the code, data, and symbol sizes are limited to 100KB + (it can be changed in the source code). - Obfuscation: +### Obfuscation: - No special effort was needed because obfuscation is almost - unavoidable for such a program :-) Defines must be used to - compress the code, and integrated i386 code generator leads to non - obvious code. +No special effort was needed because obfuscation is almost +unavoidable for such a program :-) Defines must be used to +compress the code, and integrated i386 code generator leads to non +obvious code. - Portability: +### Portability: - OTCC only works on i386 linux because it generates i386 code. OTCC - also relies on little endianness, unaligned memory accesses and - ASCII representation of characters. It also supposes that no valid - pointers are less than 512. If all those constraints are met, then - OTCC could be theoretically used to "cross compile", although no - such support is currently integrated. +`OTCC` only works on i386 linux because it generates i386 code. `OTCC` +also relies on little endianness, unaligned memory accesses and +ASCII representation of characters. It also supposes that no valid +pointers are less than 512. If all those constraints are met, then +`OTCC` could be theoretically used to "cross compile", although no +such support is currently integrated. - It was successfully compiled with gcc version 2.95.2. You get some - warnings because old K&R protos are used, some casts are implicit - and some functions are used before being defined. OTCC uses the - dynamic linker to resolve symbols with 'dlsym()', so '-ldl' must - be used as library when you compile it. +It was successfully compiled with gcc version 2.95.2. You get some +warnings because old K&R prototypes are used, some casts are implicit +and some functions are used before being defined. `OTCC` uses the +dynamic linker to resolve symbols with `dlsym()`, so `-ldl` must +be used when you compile and link it. ## Copyright and CC BY-SA 4.0 License: diff --git a/bugs.md b/bugs.md index 79f007bf4..2f2133bf1 100644 --- a/bugs.md +++ b/bugs.md @@ -918,6 +918,11 @@ would greatly appreciate anyone's help! It appears that this entry will require major debugging and to make it work one might need to have a deep understanding of the ELF format. +The author said that they compiled it with [gcc version +2.95.2](https://ftp.gnu.org/gnu/gcc/gcc-2.95.2/gcc-everything-2.95.2.tar.gz). We don't know if +a certain gcc version is necessary but it might be helpful to download and +compile that version to test it. + # 2002 There was no IOCCC in 2002.