CJIT: C, Just in Time

14 comments

• dang 3 hours ago
  Related:

  Show HN: CJIT, a single-binary C compiler that can self host - https://news.ycombinator.com/item?id=47751458 - April 2026 (1 comment)

  C, Just in Time - https://news.ycombinator.com/item?id=42246209 - Nov 2024 (7 comments)

  (Pity the Show HN didn't get attention - we'll email the author)
• apitman 2 hours ago
  Cool idea.

  I was wondering why the release explicitly is `cjit-x86_64-ubuntu-24.04` instead of generic linux, but it does in fact appear to not work on Arch:

  `tcc: error: file '/lib/x86_64-linux-gnu/libgcc_s.so.1' not found`

  I'm guessing that's due to a `dlopen` since it's not listed by `ldd`

  The TUI demos work great, but I couldn't get the SDL examples to resolve all the missing symbols after trying for a bit.
• taylorallred 2 hours ago
  Pair this with Fil-C(https://fil-c.org/) and now you have C but as a truly bonafide scripting language.
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  • rtpg 29 minutes ago
    The world-class script munging capabilities and rapid prototyping capabilities of C, combined with the durable performance of your favorite scripting language. A match made in heaven for operational scripts
  • simonask 35 minutes ago
    Which sounds a lot like the worst of all worlds.
• michaelcampbell 4 hours ago
  Looks interesting and fun, but in no instance of any C compiler I've come across is the "classic example" of "hello, world" using `fprintf(stderr, ...)`

  To each their own I guess.

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  • apitman 2 hours ago
    Give io buffering an inch and it will take a mile
• omoikane 2 hours ago
  > inspired by HolyC by Terry Davis

  Definitely was not expecting this reference.

  https://en.wikipedia.org/wiki/TempleOS#HolyC

  https://en.wikipedia.org/wiki/Terry_A._Davis

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  • BirAdam 2 hours ago
    I’m not surprised by it, but I am confused as I do not see anything that reminds me of TempleOS, HolyC, or Davis. If anything, this is just pushing the tcc —run functionality one step further.
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    • jovial_cavalier 2 minutes ago
      probably because the shell on TempleOS is actually a HolyC REPL, and HolyC is JIT compiled.
• theogravity 2 hours ago
  The site visually feels "compressed" due to the font used? It's a bit jarring. The tutorial link in the header nav doesn't go anywhere.
• gosukiwi 3 hours ago
  Did you use Codex 5.4 for the web design? :p I think Codex tends to do very similar designs, could be completely mistaken tho
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  • ethmarks 2 hours ago
    The source for the site is here: https://github.com/dyne/cjit/tree/main/docs. It's a VitePress site with a custom theme. Glancing through the code, I don't see any obvious signs of LLM coding. It also definitely wasn't created with Codex specifically, because according to the commit history, the first version of the site was in late 2024, months before Codex even released.
  • zamadatix 2 hours ago
    Looks like a generic static site generator page to me. I'd be surprised if dyne folks used a closed system like Codex specifically.
• jsLavaGoat 2 hours ago
  Inspired by Terry. But does it glow?
• grebc 2 hours ago
  Sweet project! I will give this a go today :)
• nutjob2 1 hour ago
  Much more interesting is Mir: https://github.com/vnmakarov/mir

  It has all the tools for custom JIT including a nice C compiler.
• uticus 4 hours ago
  https://dyne.org/cjit/graphics.html#cjit-for-graphical-appli...

  > Be welcome to the exciting world of graphical C applications using SDL (Simple DirectMedia Layer). SDL, originally developed by Sam Lantinga in 1998...

  That's batteries included.

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  • apitman 2 hours ago
    It links to the system SDL, on Linux at least.
• slopinthebag 1 hour ago
  > CJIT is not a tracing or adaptive JIT in the VM sense. It does not interpret first and optimize hot paths later.

  > CJIT uses TinyCC to compile C quickly, often in memory, and can execute the resulting code immediately.

  Wait, what's the difference between this and just using tinycc directly?

     cat program.c | tcc -run -
  

  Happy to be proven wrong here, since the project has been around for a couple years. It doesn't appear to just be a random AI one-shot thing.
• wavemode 1 hour ago
  > inspired by HolyC by Terry Davis

  ...in what way? o.O