https://github.com/semarie/build-rust

Script helper for building rustc and cargo from source on OpenBSD (without rustup)
https://github.com/semarie/build-rust

cargo openbsd rust

Last synced: about 1 month ago
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Script helper for building rustc and cargo from source on OpenBSD (without rustup)

• Host: GitHub
• URL: https://github.com/semarie/build-rust
• Owner: semarie
• Created: 2017-02-25T14:05:13.000Z (over 7 years ago)
• Default Branch: master
• Last Pushed: 2024-06-14T11:07:33.000Z (5 months ago)
• Last Synced: 2024-09-27T13:22:10.285Z (about 2 months ago)
• Topics: cargo, openbsd, rust
• Language: Shell
• Size: 122 KB
• Stars: 60
• Watchers: 5
• Forks: 15
• Open Issues: 1
• Metadata Files:
  • Readme: README.md

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README

        
# build-rust

build-rust is a shell script for getting a Rust beta or nightly running on

OpenBSD.

The script works by using the stable Rust from the OpenBSD package repo to

build a beta Rust, then (if you want a nightly) it uses this beta Rust to build

a nightly Rust. It also deals with ensuring the right cargo version is used at

each stage.

## Quick Start

First, choose a program to allow build-rust to be root. You usually want either

`doas` or `sudo`. E.g.:

```

echo "SUDO=doas" > ~/.build_rust.conf

```

Next:

```

$ ./build.sh init

```

This step uses the `SUDO` command you chose in the first step to install some

packages. Please read the script to ensure you are happy with the commands that

will be run as root.

Now run:

```

$ ./build.sh 

```

Where `` is either `beta` or `nightly`. If you choose `nightly` but

have not yet built  `beta`, then `beta` will be built first automatically.

Once this is done you will have a working Rust environment (including cargo) in

`install_dir/`. If you want this to be your default rustc and cargo,

then you probably want to add `install_dir//bin` to your `PATH` in your

shell rc.

## Why is the Installed Cargo Old?

The script uses the version of cargo indicated in upstream `src/stage0.txt`.

This is not necessarily the newest cargo, but is guaranteed to work for

bootstrapping.

If you would like a newer cargo, you can either manually build one off the

upstream master branch, or you can use the bootstrap cargo to install a new one

in `~/.cargo/bin`:

```

$ cargo install cargo

```

If you want that as your default cargo, don't forget to add it to the `PATH`.

## Why do we Need this Script?

Why not just use `rustup`? In short, OpenBSD has tier 3 Rust support, meaning

that the Rust upstream does not make binaries available via `rustup`. There are

a couple of reasons for this.

### Reason 1: Cross compiling.

Under normal circumstances, Rust upstream would cross compile beta and nightly

Rust on their Linux machines, making the resulting binaries available via

`rustup`. However, OpenBSD has a modified linker meaning that targeting OpenBSD

with a cross compiler is not straightforward.

### Reason 2: No Backward Compatibility

OpenBSD makes no attempt to be backward compatible. At any given time there are

two supported stable releases of OpenBSD, and a frequently regenerated

developer version called `-current`. Generally speaking, binaries from an older

stable release do not run on a newer stable release. Furthermore, there is no

guarantee that the binary built on last week's `-current` will work on this

week's. Compatibility breakage can occur not only at the library level, but

also at the ABI level.

Even if the Rust upstream could cross compile to OpenBSD, it's not clear which

version's of OpenBSD would be useful to target.