Alpine Compilation - Errors

inzanez commented 2 years ago

Hi

I am just trying to get things compiled on Alpine, but for some reason it doesn't want to build:

thread 'main' panicked at 'Unable to find libclang: "the `libclang` shared library at /usr/lib/libclang.so.10 could not be opened: Dynamic loading not supported"', /usr/local/cargo/registry/src/github.com-1ecc6299db9ec823/bindgen-0.59.2/src/lib.rs:2144:31

Not sure if that's an issue of how libreoffice-rs is built or maybe clang, ... or Alpine itself. Any idea how to fix that?

yveszoundi commented 2 years ago

I'm usually both building and running libreoffice-rs applications inside an Alpine Linux container image (musl).

Please use the Dockerfile of my document sanitizer application for packages that you might be missing (clang, etc.)
I'm hoping that you are not using any specific rust flags: i.e. i doubt that you would be able to statically link the library...

yveszoundi commented 2 years ago

Based on the applicable README instructions in the GitHub project page (Ubuntu apt-get install notes), you're "likely" missing the equivalent clang-dev apk package. Ubuntu libclang-dev == Alpine clang-dev

inzanez commented 2 years ago

I did actually install all of these. I now created a fresh Alpine container with Rust installed in it, cloned libreoffice-rs and installed pretty much all your dependencies (except the OCR stuff). I just cloned your repo and tried to build it:

/libreoffice-rs # apk add clang clang-dev clang-libs
OK: 1883 MiB in 278 packages
/libreoffice-rs # cargo build
   Compiling libreoffice-rs v0.3.2 (/libreoffice-rs)
error: failed to run custom build command for `libreoffice-rs v0.3.2 (/libreoffice-rs)`

Caused by:
  process didn't exit successfully: `/libreoffice-rs/target/debug/build/libreoffice-rs-3c006341663d6d25/build-script-build` (exit status: 101)
  --- stdout
  cargo:rustc-link-search=native=/libreoffice-rs/target/debug/build/libreoffice-rs-f55ec8fbedc916ad/out

  --- stderr
  ar: `u' modifier ignored since `D' is the default (see `U')
  thread 'main' panicked at 'Unable to find libclang: "the `libclang` shared library at /usr/lib/libclang.so.13.0.1 could not be opened: Dynamic loading not supported"', /usr/local/cargo/registry/src/github.com-1ecc6299db9ec823/bindgen-0.59.2/src/lib.rs:2144:31
  note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

Not really sure why that would happen.

yveszoundi commented 2 years ago

If following the notes below still results into problems, you'll need to provide more details about your setup (using Raspberry Pi or special CPU architecture, custom RUSTFLAGS or ~/.cargo/config.toml, custom Alpine image, etc.). I've been building libreoffice-rs almost daily for amd64 and more recently arm64 (cross-compilation) without issues.

A) Detailed notes

Clone the repository: git clone https://github.com/undeflife/libreoffice-rs/
Switch to the project folder cd libreoffice-rs
Create a Dockerfile at the root of the project (with contents to follow)
Build the Alpine container image (podman, docker, etc.) podman build -t libreoffice-build .

B) Dockerfile mentioned at step 3 in previous section

FROM docker.io/alpine:3.16

RUN apk -U upgrade && \
    apk add \
    libreofficekit \
    clang gcc clang-dev gcc cargo rust

WORKDIR /home/rust/entrusted-container
COPY . .
RUN LO_INCLUDE_PATH=/usr/include/LibreOfficeKit cargo build

C) Screenshot of build results

libreoffice-rs-build

inzanez commented 2 years ago

I am running on Docker alpine:3.16 on a normal AMD64 machine. It seems to be the Rust environment that I am using. I have not installed the default package rust or cargo, but installed it in my build-image like this:

...
 url="https://static.rust-lang.org/rustup/dist/x86_64-unknown-linux-musl/rustup-init"; \
    wget "$url"; \
    chmod +x rustup-init; \
    ./rustup-init -y --no-modify-path --default-toolchain nightly-2022-08-08 ; \
    rm rustup-init;
...

Not sure yet what implications that has, but I could imagine that the toolchain was built to do static-linking initially.

yveszoundi commented 2 years ago

I don't think that you can build with the musl toolchain... You need to use x86_64-unknown-linux-gnu

inzanez commented 2 years ago

@yveszoundi yes,...although I must admit I am not seeing through this right now. I was always under the impression that the only toolchain running on Alpine would be the musl toolchain, as it is a musl based system. Installing x86_64-unknown-linux-gnu and doing an override doesn't do the trick as cargo cannot be executed anymore. I guess I will have to dig into the cargo package in Alpine,...

inzanez commented 2 years ago

Ok, so it seems that Alpine created their own target by applying patches to the installed Rust toolchain. Like that, they are creating a toolchain called x86_64-linux-alpine-musl; this toolchain does not seem to link fully static anymore but therefore allows to build things like libreoffice-rs in a dynamically linked way.

undeflife commented 2 years ago

https://github.com/undeflife/libreoffice-rs/blob/master/build.rs#L9 Looks like this causes your compile error, it need to be musl-gcc for alpine

inzanez commented 2 years ago

@undeflife I am not sure actually; I am building on Alpine, so it should be gcc I think. At least there is no musl-gcc binary here. But I guess there is a reason that Alpine made the effort creating their own package for the Rust toolchain. Using that one works quite well,...

undeflife commented 2 years ago

issues on Alpine is all about glibc mostly , using dynamically link is a quick workaround. musl-gcc i mentioned is another option which need install manually, see wiki

yveszoundi commented 2 years ago

For reference, I managed to compile libreoffice-rs with a pristine x86_64-linux-alpine-musl stable toolchain:

I didn't play around with a project leveraging libreoffice-rs, I only built libreoffice-rs itself
rust tools were installed via rustup after following general instructions (no nightly builds, no customization)
Sample code changes to make it work

1. Changes to make it work on Alpine Musl

Cargo manifest updates

 [build-dependencies]
-bindgen = "0.59"
-
+bindgen = {version = "0.59.0", default_features = false, features = ["static"]}

Dockerfile for building libreoffice-rs

The Dockerfile file below was used to build ONLY libreoffice-rs, not a full-blown project. clang-static is required on Alpine Linux, among other dependencies.

FROM docker.io/alpine:3.16

RUN apk -U upgrade && \
    apk add curl build-base ca-certificates clang-static \
    libreofficekit libstdc++ libffi-dev zlib-dev llvm-static ncurses-dev llvm-dev \
    clang gcc clang-dev gcc cargo musl-dev musl

WORKDIR /home/rust/entrusted-container
COPY . .

RUN curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y && \
  . $HOME/.cargo/env
ENV PATH=$PATH:/root/.cargo/bin

RUN LO_INCLUDE_PATH=/usr/include/LibreOfficeKit cargo build

2. Potential issues of making it work just for libreoffice-rs

libreoffice-rs would likely need a way to optionally enable the static feature for bindgen (not sure if that's possible for the build-dependencies section in cargo: not all Linux distributions have an equivalent clang-static package.

My understanding (I could be wrong), is that cargo dependencies features are additive across dependencies (transitive dependencies included). That could be a problem with other dependencies leveraging bindgen for a given application.

undeflife / libreoffice-rs