A Small C Compiler

Related tags

Compilers 8cc
Overview

8cc C Compiler

Note: 8cc is no longer an active project. The successor is chibicc.

8cc is a compiler for the C programming language. It's intended to support all C11 language features while keeping the code as small and simple as possible.

The compiler is able to compile itself. You can see its code both as an implementation of the C language and as an example of what this compiler is able to compile.

8cc's source code is carefully written to be as concise and easy-to-read as possible, so that the source code becomes good study material to learn about various techniques used in compilers. You may find the lexer, the preprocessor and the parser are already useful to learn how C source code is processed at each stage.

It's not an optimizing compiler. Generated code is usually 2x or more slower than GCC. I plan to implement a reasonable level of optimization in the future.

8cc supports x86-64 Linux only. I have no plan to make it portable until I fix all known miscompilations and implement an optimization pass. As of 2015, I'm using Ubuntu 14 as my development platform. It should work on other x86-64 Linux distributions though.

Note: Do not have high expectations on this compiler. If you try to compile a program other than the compiler itself, there's a good chance to see compile errors or miscompilations. This is basically a one-man project, and I have spent only a few months of my spare time so far.

Build

Run make to build:

make

8cc comes with unit tests. To run the tests, give "test" as an argument:

make test

The following target builds 8cc three times to verify that stage1 compiler can build stage2, and stage2 can build stage3. It then compares stage2 and stage3 binaries byte-by-byte to verify that we reach a fixed point.

make fulltest

Author

Rui Ueyama [email protected]

Links for C compiler development

Besides popular books about compiler, such as the Dragon Book, I found the following books/documents are very useful to develop a C compiler. Note that the standard draft versions are very close to the ratified versions. You can practically use them as the standard documents.

You might also like...
C implementation of the Tiny BASIC compiler found in an article by Dr. Austin Henley

Teeny Tiny Basic A C implementation of the Tiny BASIC compiler found in this article and this github repo by Dr. Austin Henley. I did pretty well in A

bcc is an interactive compiler of a language called b.

bcc is an interactive compiler of a language called b.

This is a compiler written from scratch in C

C Compiler This is a compiler written from scratch in C, with fully supporting C18 as a goal. It can currently compile itself, and most simple program

mrcceppc is a reimplementation project for the Metrowerks mwcceppc compiler.

Compiler | mrcceppc mrcceppc is a reimplementation project for the Metrowerks mwcceppc compiler. Compiling Run generate_{version}.bat for which versio

A C header that allow users to compile brainfuck programs within a C compiler.

brainfuck.h A C header that allow users to compile brainfuck programs within a C compiler. You can insert the header into the top of your brainfuck so

Gilbraltar is a version of the OCaml compiler to be able to build a MirageOS for RaspberryPi 4.

Gilbraltar is a version of the OCaml compiler to be able to build a MirageOS for RaspberryPi 4. It's a work in progress repository to provide a dune's toolchain (as ocaml-freestanding) specialized for Raspberry Pi 4.

 NaiveCC: a compiler frontend for a subset of C
NaiveCC: a compiler frontend for a subset of C

NaiveCC: a compiler frontend for a subset of C This is a toy compiler frontend for a subset of the C programming language based on the LR(1) parsing t

A LLVM and Clang compiler toolchain built for kernel development

Cosmic-Clang Toolchain This is a LLVM and Clang compiler toolchain built for kernel development. Builds are always made from the latest LLVM sources r

A compiler written in C++ to convert .hoi code to hoi4 code

What is HC4? HC4 is a compiler that converts .hoic filenames to Hearts of Iron IV's .txt. Usage Use hc4 in the terminal (./hc4 if on Unix) and it will

Comments
  • Null dereference

    Null dereference

    There is no check for the failed malloc https://github.com/rui314/8cc/blob/b480958396f159d3794f0d4883172b21438a8597/cpp.c#L65

    may load to null deference in line https://github.com/rui314/8cc/blob/b480958396f159d3794f0d4883172b21438a8597/cpp.c#L66

    opened by QiAnXinCodeSafe 0
  • Fix 16 missing dependencies and 1 excessive dependency in Makefile

    Fix 16 missing dependencies and 1 excessive dependency in Makefile

    Hi, I've fixed 16 missing dependencies and 1 excessive dependency reported. Those issues can cause incorrect results or unnecessary rebuilds when 8cc is incrementally built. For example, any changes in "main.c" will not cause "main.o" to be rebuilt, which is incorrect. The dependency rule in line 16 of the fixed Makefile can solve the dependence issues of 14 targets, including "vector.o", buffer.o", "path.o" and etc. "8cc.h" is not read by the process when the target “utiltest" is built. Hence, the change of this file can cause an unnecessary rebuild of "utiltest", which slow down the build of the whole project. I've tested it on my computer, the fixed version worked as expected. Looking forward to your confirmation.

    Thanks Vemake

    opened by vemakereporter 0
  • Add SAVE to some other emit functions

    Add SAVE to some other emit functions

    Hi, First of all, thank you for publishing this project. I learned a lot about compiler by reading 8cc, and it led me to start writing my own Go compiler.

    When I read the generated assembly code, I've found that SAVE;is missing in emitting functions, so I added it to some of them.

    To some small functions like emit_label() and emit_jmp(), I didn't add SAVE; intentionally because it would look a bit redundant.

    Let me know if I overlooked something or went too far. Thanks again!

    opened by DQNEO 0
Owner
Rui Ueyama
Rui Ueyama
A Small C Compiler

8cc C Compiler Note: 8cc is no longer an active project. The successor is chibicc. 8cc is a compiler for the C programming language. It's intended to

Rui Ueyama 5.8k Nov 25, 2022
Smaller C is a simple and small single-pass C compiler

Smaller C is a simple and small single-pass C compiler, currently supporting most of the C language common between C89/ANSI C and C99 (minus some C89 and plus some C99 features).

Alexey Frunze 1.2k Nov 22, 2022
A C compiler for LLVM. Supports C++11/14/1z C11

The LLVM Project is a collection of modular and reusable compiler and toolchain technologies

LLVM 16.9k Nov 26, 2022
GNU Prolog is a native Prolog compiler

GNU Prolog is a native Prolog compiler with constraint solving over finite domains (FD)

Daniel Diaz 65 Nov 21, 2022
Take your first step in writing a compiler.

first-step Take your first step in writing a compiler. Building from Source Before building first-step, please make sure you have installed the follow

PKU Compiler Course 28 Aug 20, 2022
NCC is an ANSI/ISO-compliant optimizing C compiler.

The compiler is retargetable by design, but, at present, it only produces binaries for Linux/x86_64. As the compiler ABI differs somewhat from the System V ABI used by Linux, its code cannot be linked against Linux system libraries. It does, however, provide its own (incomplete) standard ANSI/Posix C library.

Charles E. Youse 0 Apr 1, 2022
nanoc is a tiny subset of C and a tiny compiler that targets 32-bit x86 machines.

nanoc is a tiny subset of C and a tiny compiler that targets 32-bit x86 machines. Tiny? The only types are: int (32-bit signed integer) char (8-

Ajay Tatachar 19 Nov 28, 2022
Microvm is a virtual machine and compiler

The aim of this project is to create a stack based language and virtual machine for microcontrollers. A mix of approaches is used. Separate memory is used for program and variable space (Harvard architecture). An interpreter, virtual machine and compiler are available. A demostration of the interpreter in action is presented below.

null 10 Aug 14, 2022
yadcc - Yet Another Distributed C++ Compiler

Yet Another Distributed C++ Compiler. yadcc是一套腾讯广告自研的分布式编译系统,用于支撑腾讯广告的日常开发及流水线。相对于已有的同类解决方案,我们针对实际的工业生产环境做了性能、可靠性、易用性等方面优化。

Tencent 271 Nov 23, 2022
Aheui JIT compiler for PC and web

아희짓 개요 아희짓은 아희 언어를 위한 JIT (Just in Time) 컴파일러입니다. 어셈블러와 유틸 라이브러리외에 외부 라이브러리에 전혀 의존하지 않고 JIT을 바닥부터 구현합니다. 지원 환경 64비트 windows, mac, linux (x86 아키텍쳐) 웹어셈

Sunho Kim 28 Sep 23, 2022