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Comment by E39M5S62 | Hacker News Reader

> DO NOT use pseudo-releases or tarballs created by third parties. In particular, automatic tarballs made by GitHub and other mirrors are lacking the .git directory and will not properly build anymore.

It's a little concerning that their build process relies on a .git directory being present. That's going to make it quite tough for packagers to actually package this.

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I think https://github.com/LuaJIT/LuaJIT/commit/6a2163a6b45d6d251599... improved things a bit, notably making automatic tarballs work again.

The export-subst attribute was new to me.

Here is a description of what it does:

If the attribute export-subst is set for a file then Git will expand several placeholders when adding this file to an archive. The expansion depends on the availability of a commit ID, i.e., if git-archive[1] has been given a tree instead of a commit or a tag then no replacement will be done. The placeholders are the same as those for the option --pretty=format: of git-log[1], except that they need to be wrapped like this: $Format:PLACEHOLDERS$ in the file. E.g. the string $Format:%H$ will be replaced by the commit hash. However, only one %(describe) placeholder is expanded per archive to avoid denial-of-service attacks.

https://git-scm.com/docs/gitattributes#_export_subst

Somewhat difficult to find on the linked list archive, but this exact issue was dicussed there. See the followup mails: https://www.freelists.org/archive/luajit/08-2023?threads=1

I'm confused what you mean. What is a packager doing here? I always assumed that the intention of this library is that you, as a developer, compile and embed it in a product that needs a scripting engine. What use would a standalone LuaJIT package be?

It's available as a package, and a library, in most Linux distributions. It includes the library and the interpreter.

edit: I have a few scripts with #!/usr/bin/luajit as the shebang line.

Interesting, that's neat. Somehow didn't realize using it like this was an option, but now that you mention it...

libluajit is a drop-in replacement for the regular liblua (v5.1)

Even ignoring the installed interpreter, libraries on Linux distributions are usually installed system-wide as their own packages which other packages depend on (neovim, mpv, cgit, etc.)

if you apt install libluajit-5.1-dev you can compile and link your c programs with it without having to compile it yourself

similarly if you are writing programs in lua rather than in c you can run them in luajit if you just apt install luajit

if you want to release your programs as free software so other people can compile and link them, it's important for them to be able to get the version of luajit you were using so they can debug why your program doesn't work in the current version of luajit

I've never needed to build LuaJIT as a git repo. Just download the tarball and did: make and make install; all I have is GNU make and GCC.

Am I missing something?

The build script changed slightly four days ago, and you will need git in the future (and build from a checkout of the repo.)

That's a shame; I thought it was one of the nice features of LuaJIT. In fact it built its own intermediate tools needed to build LuaJIT dist.

You don't need Git. It just issues a warning if it's not able to infer git information.

It could be using git submodules or tags. That isn't very concerning.

Surely a packager would be working off of the actual releases not a random git archive?

And if they can’t wait for official releases, they’d be working off of the git repo?

> Surely a packager would be working off of the actual releases not a random git archive?

There are no official releases. To quote from the linked email:

> No release tarballs or binaries are made available. Please do not use obsolete versions from older tarballs or zip files. Please remove any outdated links to these downloads -- they will cease to work soon.

The only way to get a release version of LuaJIT is to compile it from the git repo.

> The only way to get a release version of LuaJIT is to compile it from the git repo.

It will be interesting to see how this is packaged in, say, Ubuntu. Will they assign their own version numbers? Dates?

I would say something along the lines of git-describe, and packages would need to depend on the exact version.

If upstream can't commit to compatibility across release versions then I don't see it happening in distros either.

Sounds like eternal beta.

It has been an eternal, abandoned beta for many years. But sounds like work resumed now. Maybe one day it shall be stable.

The packagers can make their own snapshot, but they don't want to grab a full .git directory for the source - distributions such as Debian never want to do that: The packager is responsible for auditing all the code including copyright status in the artifacts - best not have the whole history of the project included in that case, because the task is then a little bit too big.

You can clone a specific tag or branch from a git repository without the full history. It looks like LuaJIT's git repository does not support this, although the github mirror does:

# git clone -b v2.1.ROLLING --depth 1 git@github.com:LuaJIT/LuaJIT.git

The git log looks like this:

    commit 2090842410e0ba6f81fad310a77bf5432488249a (grafted, HEAD, tag: v2.1.ROLLING)
    Author: Mike Pall <mike>
    Date:   Mon Aug 21 03:18:35 2023 +0200
    
        Merge branch 'master' into v2.1

yeah, obviously this isn't acceptable for things like debian, ubuntu, or guix

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