rust-lang/cargo · error · anyhow::Error

no {target_desc} target {named} `{target_name}`{unmatched_pa

Error message

no {target_desc} target {named} `{target_name}`{unmatched_packages}{suggestion}

What it means

Thrown by find_named_targets (src/ops/cargo_compile/unit_generator.rs:232-319) when a named target filter (--bin NAME, --example NAME, --test NAME, --bench NAME, or a glob) matches no target in the selected packages. The message includes the target description, the name/pattern, where it was looked for, a did-you-mean suggestion, and (if targets exist elsewhere) a list of available targets in other packages.

Source

Thrown at src/ops/cargo_compile/unit_generator.rs:317

                msg,
                "no {target_desc} target {named} `{target_name}`{unmatched_packages}{suggestion}",
            )?;
            if !targets_elsewhere.is_empty() {
                append_targets_elsewhere(&mut msg)?;
            } else if suggestion.is_empty() && !targets.is_empty() {
                write!(msg, "\nhelp: available {} targets:", target_desc)?;
                for (target_name, pkgs) in targets {
                    if pkgs.len() == 1 {
                        write!(msg, "\n    {target_name}")?;
                    } else {
                        for (pkg, _) in pkgs {
                            let pkg_name = pkg.name();
                            write!(msg, "\n    {target_name} in package {pkg_name}")?;
                        }
                    }
                }
            }
            anyhow::bail!(msg);
        }
        Ok(proposals)
    }

    fn get_targets_from_other_packages(
        &self,
        filter_fn: impl Fn(&Target) -> bool,
    ) -> CargoResult<Vec<(&str, Vec<&str>)>> {
        let packages = Packages::All(Vec::new()).get_packages(self.ws)?;
        let targets = packages
            .into_iter()
            .filter_map(|pkg| {
                let mut targets: Vec<_> = pkg
                    .manifest()
                    .targets()
                    .iter()
                    .filter_map(|target| filter_fn(target).then(|| target.name()))
                    .collect();

View on GitHub (pinned to 0e07a15537)

Solutions

  1. Read the 'help: available ... targets' list in the error to copy the exact name.
  2. Run `cargo build --bins`/`--help` or `cargo metadata` to enumerate real targets.
  3. Check that the target is declared in the selected package (use -p to pick the right package).
  4. If using a glob, verify the syntax and that at least one target matches.

Example fix

# before
cargo run --bin serves     # typo

# after
cargo run --bin server
Defensive patterns

Strategy: validation

Validate before calling

// Confirm a named target exists in the selected package before building.
fn target_exists(pkg: &cargo::core::Package, kind: fn(&Target)->bool, name: &str) -> bool {
    pkg.targets().iter().any(|t| kind(t) && t.name() == name)
}

Type guard

fn has_named_target(pkg: &cargo::core::Package, name: &str) -> bool {
    pkg.targets().iter().any(|t| t.name() == name)
}

Try / catch

if let Err(e) = generate_root_units {
    if e.to_string().starts_with("no ") && e.to_string().contains("target") {
        eprintln!("unknown target; see the 'available targets' list in the error");
    }
    return Err(e);
}

Prevention

When it happens

Trigger: `cargo build --bin nonexistent`, `cargo test --test missing`, `--example ghost`, or a glob like `--bin 'x*'` that matches nothing. The proposals list is empty, so the error builder assembles target_desc + named + target_name + unmatched_packages + suggestion.

Common situations: Typo in the target name. Renaming a binary/test/example without updating docs or scripts. Pointing --bin at a target defined in a dependency rather than the local package. Case mismatches.

Related errors

AI-assisted analysis of rust-lang/cargo@0e07a15537 (2026-08-06). Data as JSON: /data/errors/6ad2ab7131cc15f7.json. Report an issue: GitHub.