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

cannot override `workspace.lints` in `lints`, either remove

Error message

cannot override `workspace.lints` in `lints`, either remove the overrides or `lints.workspace = true` and manually specify the lints

What it means

Thrown by `lints_inherit_with` at src/workspace/parser/mod.rs:1165. When `[lints] workspace = true` (inherit lints from `workspace.lints`) but the same `[lints]` table also defines local lint entries, cargo refuses to merge them silently — you must either inherit fully or specify lints manually. The guard is `lints.workspace && !lints.lints.is_empty()`.

Source

Thrown at src/workspace/parser/mod.rs:1165

    get_ws_inheritable: impl FnOnce() -> CargoResult<T>,
) -> CargoResult<T> {
    match field {
        manifest::InheritableField::Value(value) => Ok(value),
        manifest::InheritableField::Inherit(_) => get_ws_inheritable().with_context(|| {
            format!(
                "error inheriting `{label}` from workspace root manifest's `workspace.package.{label}`",
            )
        }),
    }
}

fn lints_inherit_with(
    lints: manifest::InheritableLints,
    get_ws_inheritable: impl FnOnce() -> CargoResult<manifest::TomlLints>,
) -> CargoResult<manifest::TomlLints> {
    if lints.workspace {
        if !lints.lints.is_empty() {
            anyhow::bail!(
                "cannot override `workspace.lints` in `lints`, either remove the overrides or `lints.workspace = true` and manually specify the lints"
            );
        }
        get_ws_inheritable().with_context(
            || "error inheriting `lints` from workspace root manifest's `workspace.lints`",
        )
    } else {
        Ok(lints.lints)
    }
}

fn dependency_inherit_with<'a>(
    dependency: manifest::InheritableDependency,
    name: &str,
    inherit: &dyn Fn() -> CargoResult<&'a InheritableFields>,
    package_root: &Path,
    edition: Edition,
    warnings: &mut Vec<String>,

View on GitHub (pinned to 0e07a15537)

Solutions

1. Remove the local `[lints.<tool>]` entries so only `workspace = true` remains.
2. Or drop `workspace = true` and manually specify every lint in the member.

Example fix

# before
[lints]
workspace = true
[lints.rust]
unsafe_code = "warn"
# after (inherit fully)
[lints]
workspace = true
# (move unsafe_code to [workspace.lints.rust] in the root)

if let Some(lints) = doc.get("lints").and_then(|i| i.as_table_like()) {
    let inherits = lints.get("workspace").and_then(|v| v.as_bool()) == Some(true);
    let has_local = lints.iter().any(|(k, _)| k != "workspace");
    if inherits && has_local {
        return Err("cannot mix [lints] workspace=true with local lints".into());
    }
}

When it happens

Trigger: A member manifest with `[lints]\nworkspace = true\n[lints.rust]\nunsafe_code = "warn"` — both inheritance and a local override present.

Common situations: Enabling workspace lint inheritance then adding a one-off lint; merging configs during a refactor; copying a member manifest and leaving stale entries.

Related errors

• package `{}` cannot be tested because it requires dev-depend
• {}package(s) `{}` not found in workspace `{}`
• no library targets found in packages: {}
• found a virtual manifest at `{}` instead of a package manife
• you can't generate a lockfile for an empty workspace.

AI-assisted analysis of rust-lang/cargo@0e07a15537 (2026-08-06). Data as JSON: /data/errors/1b0a3089e711294a.json. Report an issue: GitHub.