Feature for static linking build

[izderadicka]

I want to use rust_icu_col in building fully statically linked binary. I'm building on alpine with RUSTFLAGS="-C target-feature=+crt-static -C link-self-contained=yes"

Problem here is that I'm getting this error when rust_icu_sys is compiled:

thread 'main' panicked at 'Unable to find libclang: "the `libclang` shared library at /usr/lib/libclang.so.11.1 could not be opened: Dynamic loading not supported"', /root/.cargo/registry/src/github.com-1ecc6299db9ec823/bindgen-0.53.3/src/lib.rs:1956:31

I do have static version of libclang - e.g libclang.a on system, but build is still preferring dynamic version.

In my other projects I' m using feature static which will enforce println!("cargo:rustc-link-lib=static=ssl"); (here should be clang) for dependant C libraries.

However I'm not sure how to do it for indirect dependencies - e.g. you depend on C library and I depend on your crate.

I guess same will be for icu C library, but just hit clang first.

[filmil]

It looks like a feature flag would work to emit the correct settings. WDYT?

…

On Thu, Nov 25, 2021 at 10:31 AM Ivan Zderadicka ***@***.***> wrote: I want to use rust_icu_col in building fully statically linked binary. I'm building on alpine with RUSTFLAGS="-C target-feature=+crt-static -C link-self-contained=yes" Problem here is that I'm getting this error when rust_icu_sys is compiled: thread 'main' panicked at 'Unable to find libclang: "the `libclang` shared library at /usr/lib/libclang.so.11.1 could not be opened: Dynamic loading not supported"', /root/.cargo/registry/src/github.com-1ecc6299db9ec823/bindgen-0.53.3/src/lib.rs:1956:31 I do have static version of libclang - e.g libclang.a on system, but build is still preferring dynamic version. In my other projects I' m using feature static which will enforce println!("cargo:rustc-link-lib=static=ssl"); (here should be clang) for dependant C libraries. However I'm not sure how to do it for indirect dependencies - e.g. you depend on C library and I depend on your crate. I guess same will be for icu C library, but just hit clang first. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#228>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAB4GMD3CGTL4NGA6F5KPSDUNZ6HRANCNFSM5IZD4WIA> . Triage notifications on the go with GitHub Mobile for iOS <https://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675> or Android <https://play.google.com/store/apps/details?id=com.github.android&referrer=utm_campaign%3Dnotification-email%26utm_medium%3Demail%26utm_source%3Dgithub>.

[izderadicka]

Yes, feature flag would be great.

I finally was able to do a static build against rust_icu_col, but it took this:

• build in alpine with taget x86_64-unknown-linux-musl
• need to install static libs for icu a clang
• use rust_icu_col without default features, just with rename and icu_version_in_env
• use environment vars:

export RUST_ICU_MAJOR_VERSION_NUMBER=67
export RUSTFLAGS="-C target-feature=+crt-static -C link-self-contained=yes -L native=/usr/lib -l static=clang -l static=icui18n -l static=icuuc -l static=icudata -l static=stdc++"

Some of the complexity is caused by Rust complicated approach to static build, but for rest static feature in rust_icu will help.
From what I have seen bindgen has static feature too, which might be useful.

[filmil]

Feel free to contribute a patch that handles your use case. It looks like you've already done the legwork, so I hope it shouldn't be too complicated.