Missing rust library libunicode_width.rlib when building chromium-x11 from scarthgap branch

[ghuband]

meta-browser/scarthgap
meta-clang/scarthgap-clang20
meta-lts-mixins/scarthgap/rust

from log.do_compile:

[145/57407] ln -f obj/build/rust/std/lib/libunicode_width.rlib prebuilt_rustc_sysroot/lib/rustlib/x86_64-poky-linux-gnu/lib/libunicode_width.rlib 2>/dev/null || (rm -rf prebuilt_rustc_sysroot/lib/rustlib/x86_64-poky
-linux-gnu/lib/libunicode_width.rlib && cp -af obj/build/rust/std/lib/libunicode_width.rlib prebuilt_rustc_sysroot/lib/rustlib/x86_64-poky-linux-gnu/lib/libunicode_width.rlib)
FAILED: prebuilt_rustc_sysroot/lib/rustlib/x86_64-poky-linux-gnu/lib/libunicode_width.rlib
ln -f obj/build/rust/std/lib/libunicode_width.rlib prebuilt_rustc_sysroot/lib/rustlib/x86_64-poky-linux-gnu/lib/libunicode_width.rlib 2>/dev/null || (rm -rf prebuilt_rustc_sysroot/lib/rustlib/x86_64-poky-linux-gnu/l
ib/libunicode_width.rlib && cp -af obj/build/rust/std/lib/libunicode_width.rlib prebuilt_rustc_sysroot/lib/rustlib/x86_64-poky-linux-gnu/lib/libunicode_width.rlib)
cp: cannot stat 'obj/build/rust/std/lib/libunicode_width.rlib': No such file or directory

Any help is appreciated.

I have been having the same issue.

Summary

Building Chromium from meta-browser (scarthgap branch) fails during do_compile while staging the Rust stdlib sysroot. The build stops because libunicode_width.rlib is expected but not found.

This looks like the same class of problem as #792 (Rust-enabled Chromium + stdlib discovery/staging). #792 was closed via #809, but I’m still hitting a variant of the issue on Scarthgap with Chromium 138.

Repo: https://github.com/OSSystems/meta-browser (meta-chromium)

Versions / Context

• Yocto: Scarthgap
• meta-browser: scarthgap branch (commit: 168d284276730e7109426075a1c53ab2fc677639)
• meta-chromium recipe: chromium-x11 138.0.7204.157 (from layer index)
• Host: Debian build server, build executed inside Docker container (I control the image/packages)
• Rust/libstd: I initially used the Rust toolchain provided by OE/Scarthgap (libstd-rs 1.75.0 is what scarthgap core provides) and also tried adjustments described below.

Build Command

bitbake chromium-x11

Expected Result

Chromium compiles successfully; Rust stdlib staging should populate prebuilt_rustc_sysroot/.../lib/ with the required .rlib files.
Actual Result (failure)
During do_compile, Ninja fails while copying/linking Rust stdlib artifacts into prebuilt_rustc_sysroot, because obj/build/rust/std/lib/libunicode_width.rlib does not exist.

Log excerpt:

FAILED: prebuilt_rustc_sysroot/lib/rustlib/<target>/lib/libunicode_width.rlib
ln -f obj/build/rust/std/lib/libunicode_width.rlib prebuilt_rustc_sysroot/lib/rustlib/<target>/lib/libunicode_width.rlib 2>/dev/null || \
  (rm -rf prebuilt_rustc_sysroot/lib/rustlib/<target>/lib/libunicode_width.rlib && \
   cp -af obj/build/rust/std/lib/libunicode_width.rlib prebuilt_rustc_sysroot/lib/rustlib/<target>/lib/libunicode_width.rlib)
cp: cannot stat 'obj/build/rust/std/lib/libunicode_width.rlib': No such file or directory
ninja: build stopped: subcommand failed.

What I tried (based on #792 / #809)

I read through #792, which references a fix in #809. In the #792 discussion, the Rust stdlib directory contains hashed rlibs (e.g. libunicode_width-.rlib) and the staging logic is involved. (#792 also includes a suggested diff for rust_%.bbappend.)

In my current scarthgap checkout, I did not have the same rust_%.bbappend and libstd-rs_%.bbappend appends available, so I copied the two appends used to address #792/#809 into my own layer and performed a clean rebuild. The failure persists: neither rust nor libstd-rs appears to produce a plain libunicode_width.rlib, and the chromium build still expects it.

I also attempted clean rebuilds (cleansstate / fresh tmp/work), but the missing libunicode_width.rlib remains.

[developsessions]

I have the same issue but I build for wayland.

bitbake chromium-ozone-wayland

[developsessions]

The issue is maybe that the meta-lts-mixins/scarthgap/rust version of rust is too new for the chromium version of scarthgap from the meta-browser layer.

[ghuband]

From the git log for meta-browser/scrathgap

Test dependencies:
------------------

* URI: git://git.yoctoproject.org/poky
  - branch: scarthgap
  - revision: ac257900c33754957b2696529682029d997a8f28

* URI: git://git.openembedded.org/meta-openembedded
  - layers: meta-oe
  - branch: scarthgap
  - revision: 491671faee11ea131feab5a3a451d1a01deb2ab1

* URI: git://github.com/kraj/meta-clang
  - branch: scarthgap-clang20
  - revision: 76596813cd0061bd9818a80926e6900af61fcaa0

* URI: git://git.yoctoproject.org/meta-lts-mixins
  - branch: scarthgap/rust
  - revision: 96deb45139df027473faf0938fe006d33c45c375

The meta-lts-mixins revision is dated August 2025 and is 30 commits behind HEAD.
I'll try to re-build Rust using 96deb45139df027473faf0938fe006d33c45c375 and then re-build Chromium.

[developsessions]

Ahh, I didn't see the revision info. But I already tried to go some commits back, but not too far.
I will also try 96deb45139 now. Thanks!

[ghuband]

With the meta-lts-mixins revision set to 96deb45139df027473faf0938fe006d33c45c375, my chromium-x11 build completed without errors.

Same Here.. I am able to do a full build. I guess we will be stuck with this version of chromium for some time.

With the meta-lts-mixins revision set to 96deb45139df027473faf0938fe006d33c45c375, my chromium-x11 build completed without errors.

[developsessions]

Mine compiles too for wayland.