What is this?
A documented tutorial series where the author builds a self-compiling compiler for a subset of the C language, split into roughly 64 incremental parts, each with working source code and a written explanation of the theory behind it.
A documented tutorial series where the author builds a self-compiling compiler for a subset of the C language, split into roughly 64 incremental parts, each with working source code and a written explanation of the theory behind it.Is this a working compiler or just a tutorial?Both — each numbered part adds real C source code to a growing compiler, paired with an explanation of what changed and why, so you end up with a functioning compiler as well as the story of how it was built.
Both — each numbered part adds real C source code to a growing compiler, paired with an explanation of what changed and why, so you end up with a functioning compiler as well as the story of how it was built.Where should I start reading?Start at Part 0 (Introduction to the Journey) and go through the parts in order up to Part 64; each part's code builds directly on the previous one.
Start at Part 0 (Introduction to the Journey) and go through the parts in order up to Part 64; each part's code builds directly on the previous one.Do I need anything special to follow along?Just a C compiler and basic C knowledge — the project itself is written entirely in C with no external dependencies, Docker, or build system beyond standard tooling.
Just a C compiler and basic C knowledge — the project itself is written entirely in C with no external dependencies, Docker, or build system beyond standard tooling.Is this still being actively updated?No, the author stopped adding new parts to acwj and moved on to writing a brand-new language called 'alic' from scratch.
No, the author stopped adding new parts to acwj and moved on to writing a brand-new language called 'alic' from scratch.Is the whole repo under one license?No — the source code and scripts are GPL-3.0, but the written English documents and images are licensed separately under Creative Commons BY-NC-SA 4.0, which restricts commercial reuse of the text.
No — the source code and scripts are GPL-3.0, but the written English documents and images are licensed separately under Creative Commons BY-NC-SA 4.0, which restricts commercial reuse of the text.What target does the compiler generate code for?It generates ARM assembly directly starting around Part 14, and the later parts add alternative backends using QBE (Part 63) and for the 6809 CPU (Part 64).
It generates ARM assembly directly starting around Part 14, and the later parts add alternative backends using QBE (Part 63) and for the 6809 CPU (Part 64).Does it compile all of C?No, only a deliberately limited subset of C — just enough for the compiler to be self-hosting, meaning it can eventually compile its own source code.
No, only a deliberately limited subset of C — just enough for the compiler to be self-hosting, meaning it can eventually compile its own source code.Did the author write every part from scratch?Not entirely — some code and many ideas were borrowed from Nils M Holm's public-domain SubC compiler, though the author considers the result different enough to license separately.
Not entirely — some code and many ideas were borrowed from Nils M Holm's public-domain SubC compiler, though the author considers the result different enough to license separately.What are similar projects?compiler, os-tutorial, lytlnyblOS, linux-insides, chibicc, cpu-performance-engineering, flash-linux0.11-talk, lowlevelprogramming-university
compiler, os-tutorial, lytlnyblOS, linux-insides, chibicc, cpu-performance-engineering, flash-linux0.11-talk, lowlevelprogramming-universityWhich topics is it in?compilers, assembly, parsing, parser, programming-language, academic, systems-programming, computer-science, compiler, c, guide, learning-resources
compilers, assembly, parsing, parser, programming-language, academic, systems-programming, computer-science, compiler, c, guide, learning-resources