Hi there,
I'm trying to do some native windows rust programming. I'm using native-windows-gui and native-windows-derive to do it, but if I try to mix that with tokio, I get the following:
No entry point found error for GetWindowSubclass. On console, I get:
error: process didn't exit successfully: `C:\source\myprojectanem\target\debug\myprojectname.exe` (exit code: 0xc0000139, STATUS_ENTRYPOINT_NOT_FOUND)
If I change
#[tokio::main]
async fn main() {
to:
fn main() {
The problem goes away, but obviously I can't use tokio then.
Any clue what the problem is and how to fix it?
Apparently the problem is due to an incompatibility between the use of certain libraries (winapi and windows-sys) which use different versions of COM. At least so I deduce from the documentation I've read.
There's a workaaround:
On Cargo.toml, use.
[build-dependencies] embed-manifest = "1.3.1"And on the root of the project (not the src dir) create a build.rs file with the following content:
use embed_manifest::{embed_manifest, new_manifest}; fn main() { if std::env::var_os("CARGO_CFG_WINDOWS").is_some() { embed_manifest(new_manifest("Contoso.Sample")).expect("unable to embed manifest file"); } println!("cargo:rerun-if-changed=build.rs"); }This embeds a manifest together with the executable, solving the issue.
wouldn't it be better to use
#[cfg(target_os = "windows")]instead of checking an env variable?Reference: https://doc.rust-lang.org/rust-by-example/attribute/cfg.html
