Use
[`command`](https://www.gnu.org/software/bash/manual/bash.html#index-command)
instead of `which` to check if `wild` is installed.
Using `which` will result in an error being printed to stdout:
```bash
./script/install-wild
which: invalid option -- 's'
/usr/local/bin/wild
Warning: existing wild 0.6.0 found at /usr/local/bin/wild. Skipping installation.
```
Release Notes:
- N/A
Follows on from
https://github.com/zed-industries/zed/pull/37717#discussion_r2376739687
@dvdsk suggested this but I didn't get to it in the previous PR.
# Tested
```
; sudo rm /usr/local/bin/wild
; ./script/install-wild
Downloading from https://github.com/davidlattimore/wild/releases/download/0.6.0/wild-linker-0.6.0-x86_64-unknown-linux-gnu.tar.gz
Wild is installed to /usr/local/bin/wild
To make it your default, add or merge these lines into your ~/.cargo/config.toml:
[target.x86_64-unknown-linux-gnu]
linker = "clang"
rustflags = ["-C", "link-arg=--ld-path=wild"]
[target.aarch64-unknown-linux-gnu]
linker = "clang"
rustflags = ["-C", "link-arg=--ld-path=wild"]
```
```
; sudo rm /usr/local/bin/mold
; ./script/install-mold 2.34.0
Downloading from https://github.com/rui314/mold/releases/download/v2.34.0/mold-2.34.0-x86_64-linux.tar.gz
Mold is installed to /usr/local/bin/mold
To make it your default, add or merge these lines into your ~/.cargo/config.toml:
[target.'cfg(target_os = "linux")']
linker = "clang"
rustflags = ["-C", "link-arg=-fuse-ld=mold"]
```
Release Notes:
- N/A
Wild changed in 0.6.0 to using gzip rather than xz, and changed the
format of the package name.
Follows on from and fixes
https://github.com/zed-industries/zed/pull/37717
cc @dvdsk @mati865
Release Notes:
- N/A
# Summary
Today, Zed uses Mold on Linux, but Wild can be significantly faster.
On my machine, Wild is 14% faster at a whole-tree clean build, 20%
faster on an incremental build with a minimal change, and makes no
measurable effect on runtime performance of tests.
However, Wild's page says it's not yet ready for production, so it seems
to early to switch for production and CI builds.
This PR keeps using Mold in CI and lets developers choose in their own
config what linker to use. (The downside of this is that after landing
this change, developers will have to do some local config or it will
fall back to the default linker which may be slower.)
[Wild 0.6 is out, and their announcement has some
benchmarks](https://davidlattimore.github.io/posts/2025/09/23/wild-update-0.6.0.html).
cc @davidlattimore from Wild, just fyi
# Tasks
- [x] Measure Wild build, incremental build, and runtime performance in
different scenarios
- [x] Remove the Linux linker config from `.cargo/config.toml` in the
tree
- [x] Test rope benchmarks etc
- [x] Set the linker to Mold in CI
- [x] Add instructions to use Wild or Mold into `linux.md`
- [x] Add a script to download Wild
- [x] Measure binary size
- [x] Recommend Wild from `scripts/linux`
# Benchmarks
| | wild 0.6 (rust 1.89) | mold 2.37.1 (1.89) | lld (rust 1.90) | wild
advantage |
| -- | -- | -- | -- | -- |
| clean workspace build | 176s | 184s | 182s | 5% faster than mold |
| nextest run workspace after build | 137s | 142s | 137s | in the noise?
|
| incremental rebuild | 3.9s | 5.0s | 6.6s | 22% faster than mold |
I didn't observe any apparent significant change in runtime performance
or binary size, or in the in-tree microbenchmarks.
Release Notes:
- N/A
---------
Co-authored-by: Mateusz Mikuła <oss@mateuszmikula.dev>