Getting NotSupported(NotSupportedError) when creating an EventLoop under X11

[StealthyKamereon]

Description

I'm trying to run an application that uses winit. When I launch it it crashes on the following line :

let event_loop = EventLoop::new().unwrap();

I then made a dummy Rust package with only this line and sure enough I have the same crash.

OS and window mananger

I am on Nixos and using Plasma 5.

Winit version

0.29.15

[notgull]

NixOS

Please ensure that all of the following libraries are installed:

• libx11-dev
• libxcursor-dev
• libxcb1-dev
• libxi-dev
• libxkbcommon-dev
• libxkbcommon-x11-dev

[StealthyKamereon]

It is indeed the problem.
Being on Nixos, dynamically loaded libraries are a bit of a hassle.

I'm closing this ticket as it's not really a bug of winit but rather its underlying lib: x11-rs
I'll write the solution here later when / if I find it for future people that come across this problem.

Thanks

[StealthyKamereon]

The correct way to do this in Nixos to my understanding is to use nix-ld.

Adding this snippet should enable nix-ld to provide path to the required libs :

programs.nix-ld.enable = true;
programs.nix-ld.libraries = with pkgs; [
    xorg.libX11
    xorg.libXcursor
    xorg.libxcb
    xorg.libXi
    libxkbcommon
];

Unfortunately, it still doesn't work for some reason (see nix-community/nix-ld-rs#26).
The current workaround I found is to set the content of LD_LIBRARY_PATH manually before running the binary:

export LD_LIBRARY_PATH=$NIX_LD_LIBRARY_PATH

I am still looking for a better solution.

[nuxeh]

For what it's worth, I got a similar app with the same error to work using a modification of the nix shell here https://discourse.nixos.org/t/could-not-find-system-library-x11-required-by-the-x11-crate/33751

[freddycansic]

My solution was to include a build.rs in the root directory of the cargo project.

fn main() {
    println!(
        "cargo:rustc-link-search={}",
        std::env::var("NIX_LD_LIBRARY_PATH").unwrap_or_default()
    );
}

This adds NIX_LD_LIBRARY_PATH to the rustc linker library search paths.

Still, it would be nice to use a Nix specific solution.

Reference: https://doc.rust-lang.org/cargo/reference/build-scripts.html

[kchibisov]

just export LD_LIBRARY_PATH from the nix expression, it has an option to populate this variable. Or you fhs.