Rust flo_draw graphics library is not building

Question

The issue I'm having are regarding a copy-pasted flo_draw example program. I am using vscode and the rust-anylizer extension. It tells me failed to run build scripts, check server logs for more information apon copying the code in. I don't know how to check these or what they are. Using cargo run from the terminal yields no better results.

I tried to copy in the code below:

// src.main.rs
use flo_draw::*;
use flo_draw::canvas::*;

fn main() {
with_2d_graphics(|| {
let canvas = create_canvas_window("Hello, world");
});
}

$ cargo run
Compiling futures v0.3.25
Compiling semver v0.11.0
Compiling flo_render_gl_offscreen v0.3.0
Compiling allsorts v0.5.1
Compiling winit v0.24.0
error: failed to run custom build command for `flo_render_gl_offscreen v0.3.0`

Caused by:
process didn't exit successfully: `/<path to program>/target/debug/build/flo_render_gl_offscreen-9d539a79f1cb257c/build-script-build` (exit status: 101)
\--- stderr
thread 'main' panicked at 'Unable to find libclang: "couldn't find any valid shared libraries matching: \['libclang.so', 'libclang-*.so', 'libclang.so.*', 'libclang-*.so.*'\], set the `LIBCLANG_PATH` environment variable to a path where one of these files can be found (invalid: \[\])"', /<path to home>/.cargo/registry/src/github.com-1ecc6299db9ec823/bindgen-0.54.0/src/lib.rs:1959:31
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
warning: build failed, waiting for other jobs to finish...

Answer 1

flo_draw , or, more specifically, one of its dependencies, links to the external C library and therefore have to generate the matching API. This is done using bindgen , which requires clang to be installed in your system.

Installation instructions from the linked page:

Debian-based Linuxes

 # apt install llvm-dev libclang-dev clang

Ubuntu 18.04 provides the necessary packages directly.

Arch

# pacman -S clang

Fedora

# dnf install clang-devel