Unable to find libclang: "the libclang shared library

[cuifox]

apk info clang-dev
clang15-dev-15.0.5-r0 description:
A C language family front-end for LLVM (development files)

clang15-dev-15.0.5-r0 webpage:
https://llvm.org/

clang15-dev-15.0.5-r0 installed size:
21 MiB

cat /etc/alpine-release
3.15.1

--- stderr
thread 'main' panicked at 'Unable to find libclang: "the libclang shared library at /usr/lib/libclang.so.15.0.5 could not be opened: Dynamic loading not supported"', /root/.cargo/registry/src/mirrors.ustc.edu.cn-12df342d903acd47/bindgen-0.60.1/src/lib.rs:2172:31

[pvdrz]

well this says that dynamic loading is not supported, what happens if you use the static feature of bindgen?

EDIT: the runtime feature is enabled by default so you have to disable default features first. See https://docs.rs/crate/bindgen/0.60.1/features

[pvdrz]

A similar (but not exactly the same) issue happens here Rust-for-Linux/linux#934 and I suspect it is because the clang-sys version we use does not support clang 15.

We will update the clang-sys version and do a new release as soon as possible.

[Karrq]

Hello, I have the same issue but I'm using the latest version of bindgen (tried a couple of older versions too) and clang 12 with alpine 3.15.8

Unable to find libclang: "the `libclang` shared library at /usr/lib/libclang.so.12 could not be opened: Dynamic loading not supported

[pvdrz]

@Karrq have you tried this?

well this says that dynamic loading is not supported, what happens if you use the static feature of bindgen?

EDIT: the runtime feature is enabled by default so you have to disable default features first. See https://docs.rs/crate/bindgen/0.60.1/features

[Karrq]

@pvdrz I did, but then this is the error #2333

[Karrq]

I found the root cause: rust-lang/cargo#4423

I'm in a cross-compilation environment, thus RUSTFLAGS are ignored. The only sensible workaround (that I found for now) is using the host-config unstable feature

[quadroli]

Helloo 👋🏼
I'm getting the same same issue as well while trying to build wl-screenrec
I'm on Alpine Linux 3.19, and trying to use libclang16

Exact error message: Unable to find libclang: "the `libclang` shared library at /usr/lib/llvm16/lib/libclang.so.16.0.6 could not be opened: Dynamic loading not supported"

[quadroli]

How did you all work your way around this ?

[bnusunny]

I had the same issue on Alpine Linux 3.20 and found one workaround. Here are the steps:

1. Enable the static feature for bindgen in Cargo.toml

[build-dependencies]
bindgen = { version = "0.70", default-features=false, features = ["logging", "prettyplease", "static"] }

2. Create a shell script in your project

#!/bin/bash
if [ "$1" = "--libs" ]; then
    /usr/bin/llvm-config "$@" "--link-static"
else
    /usr/bin/llvm-config "$@"
fi

You may need to adjust the /usr/bin/llvm-config path dependending on your system configuration.

And make it executable: chmod +x /path/to/the/script

3. Set environment variable LLVM_CONFIG_PATH to the shell script created in the step 2.

export LLVM_CONFIG_PATH=/path/to/the/script

The last 2 steps is to workaround a bug in clang-sys here. It misses --link-static option when using llvm-config to list the static libs (.a). Without that option, llvm-config gives the dynamic libs (.so).