Build Dot C

A self-hosting build system for C/C++ projects, configured entirely in a single build.c file.
The build executable will automatically rebuild itself when changes are detected in build.c.

Features

• Simple, single-file build configuration (build.c)
• Supports debug and release builds
• Automatic dependency tracking via -MD
• Cleans output directory
• Passes arguments to the built executable
• Self-rebuilding when build.c changes
• Optional multithreaded compilation

Usage

./build [dbg|rel|clean|no-threading|build-only|j [NUM]|version|help] -- [ARGS...]

Commands

• dbg : Build the target executable with -DDEBUG and debug info
• rel : Build the target executable with -DRELEASE and optimizations
• clean : Remove the output directory
• no-threading : Disable multithreaded compilation
• build-only : Only build the build executable, not the target
• j [NUM] : Sets the number of threads to use for building source files\n"
• version : Print the build system version
• help : Show help text
• -- : Run the built executable, passing any arguments after -- to it

Example

./build dbg -- --input=foo.txt
./build rel
./build rel j64
./build clean
./build no-threading

Configuration

Edit the top of build.c to set:

• cc.c : C Compiler for target (default: "gcc")
• cc.cpp : C++ Compiler for target (default: "g++")
• exe : Name of the target executable
• dir : Output directory
• src[] : List of source files to compile
• flags[] : Compiler flags
• incs[] : Directories to include
• lib_incs[] : Directories to include for linking to libraries
• libs[] : Libraries to link
• build.cc : Compiler for build.c
• build.file : Path to build.c
• build.exe : Name of the build executable
• build.ver : Version string

How it works

• On each invocation, build checks if build.c or the build mode has changed.
• If so, it rebuilds itself, then re-invokes with the same arguments.
• Otherwise, it checks dependencies and only recompiles changed files.
• Output and intermediate files are placed in the directory specified by dir.
• Uses a lock file to track build state and avoid concurrent builds.

License

MIT License. See top of build.c or the LICENCE.md file for details.