Release build runs, debug build fails

Hi all,
I have a reduced version of a program here, that builds fine.
However, when I try to run it, using cargo run or building and then executing from the command line, the debug build comes back with

error: could not execute process `target\debug\p16_fake_search_select.exe` (never executed)

Caused by:
  Access is denied. (os error 5)

or a variant of that (this example is from cargo run) . Furthermore, at the moment of calling the exe, it is removed (!) from the file system.
A release build works as expected.
The same .exe files on another PC have the same behaviour. BTW: I am on W10 machines.
And it all runs fine in the Playground.

This is the code. If you comment in the line //let period = 100; both debug and release builds run fine.

use rand::prelude::*;

// These crates need dependencies in Cargol.toml
use tokio::sync::mpsc;   // oneshot; // , mpsc, oneshot};
use tokio::time::{sleep, Duration};

type Rslt = String;

async fn main() {
    let results = google("golang").await;
    println!("Results: {:?}", results);

// Two other versions of this fake searcher have been deleted for isolating the bug 
async fn video(query: String) -> Rslt {
    let period = thread_rng().gen_range(0..=100);
    //let period = 100;
    format!("{} result for {}", "Video", query)

async fn google(query: &str) -> Vec<Rslt> {

    let query = query.to_string();
    let (tx0, mut rx) = mpsc::channel::<String>(1);
    // Spawning 2 other similar processes has been deleted for isolating the bug
    tokio::spawn(async move { tx0.send(video(query).await).await.unwrap(); });

    let mut result = Vec::new();
    // The original tokio::select! has been deleted for isolating the bug
    while let Some(msg) = rx.recv().await { 

Anyone have a clue what's going on here?

I would check my AV logs if that happened to me

1 Like

Do you have another instance of cargo run running in the background? If the p16_fake_search_select.exe executable is being used, rustc won't be able to save the new executable and your build will fail.

period remains a range. If you sample an integer from this range it may work:

let mut rng = thread_rng().gen_range(0..=100);
let period = rng.gen();

No, gen_range produces one value within the given range.
(But this point shouldn't matter for issues between debug and release.)

AV logs?

The problem is not in the building: the executable is produced when building.
The problem is in the running: the executable is consumed the moment you run it, either immediately with cargo run or delayed when activating it through a command prompt.

Antivirus program. Looks like it treats your release build as suspicious and deletes it before Cargo starts it.

1 Like

I could not find anything in the AV logs.
Anyway: I do not know what happened, but today I can run all variants of the program (full, reduced, with any of the two lines commented in or out) without problems.
I guess it has not to do with rustc, but with something else on my system (which is partly under group administator control).
Thank you all for thinking along.