feat(diag): Stabilize cargo-lints

crates/xtask-lint-docs/src/main.rs

@@ -45,11 +45,7 @@ fn main() -> anyhow::Result<()> {
 >
 > See [the lints section in the Manifest Format
 > chapter](manifest.md#the-lints-section) to configure lint levels for tools
-> such as `rustc` or `clippy`.
-
-> [!WARNING]
-> [Cargo's linting system is unstable](unstable.md#lintscargo) and can only be used on nightly
-> toolchains."
+> such as `rustc` or `clippy`."
     )?;
     writeln!(buf)?;
 

doc/book/src/guide/build-performance.md

@@ -151,16 +151,11 @@ Trade-offs:
 
 ### Removing unused dependencies
 
-Recommendation: periodically review unused dependencies for removal using:
-```console
-$ cargo +nightly check -Zcargo-lints --workspace --all-targets
-```
-This may have false positives from:
-- when a dependency's use is dynamically controlled by a `build.rs` or `RUSTFLAGS`
+The [`cargo::unused_dependencies`](../reference/lints.md#unused_dependencies) will identify most unused dependencies with few false positives.
 
-Also, periodically review hidden [`cargo::unused_dependencies`] results:
+For everything else, periodically review hidden [`cargo::unused_dependencies`] results:
 ```console
-$ CARGO_LOG=cargo::diagnostics::rules::unused_dependencies=debug cargo +nightly check -Zcargo-lints --workspace --all-targets
+$ CARGO_LOG=cargo::diagnostics::rules::unused_dependencies=debug cargo check --workspace --all-targets
 ```
 This will show potential unused dependencies for
 - registry and git dependencies
@@ -174,10 +169,8 @@ it can be easy to miss that a dependency is no longer used and can be removed.
 
 Trade-offs:
 - ✅ Faster full build and link times
-- ❌ **Requires using nightly Rust and an [unstable Cargo feature][cargo-lints] when reviewing unused dependencies**
 - ❌ It takes effort to identify unused dependencies from among the false positives
 
-[cargo-lints]: ../reference/unstable.md#lintscargo
 [`cargo::unused_dependencies`]: ../reference/lints.md#unused_dependencies
 [`package.rust-version`]: ../reference/rust-version.md
 

doc/book/src/reference/lints.md

@@ -7,10 +7,6 @@
 > chapter](manifest.md#the-lints-section) to configure lint levels for tools
 > such as `rustc` or `clippy`.
 
-> [!WARNING]
-> [Cargo's linting system is unstable](unstable.md#lintscargo) and can only be used on nightly
-> toolchains.
-
 
 
 | Group                | Description                                                                         | Default level |

doc/book/src/reference/unstable.md

@@ -116,7 +116,6 @@ Each new feature described below should explain how to use it.
     * [per-package-target](#per-package-target) --- Sets the `--target` to use for each individual package.
     * [artifact dependencies](#artifact-dependencies) --- Allow build artifacts to be included into other build artifacts and build them for different targets.
     * [Profile `trim-paths` option](#profile-trim-paths-option) --- Control the sanitization of file paths in build outputs.
-    * [`[lints.cargo]`](#lintscargo) --- Allows configuring lints for Cargo.
     * [path bases](#path-bases) --- Named base directories for path dependencies.
     * [`unstable-editions`](#unstable-editions) --- Allows use of editions that are not yet stable.
 * Information and metadata
@@ -1756,27 +1755,6 @@ Use fine grain locking instead of locking the entire build cache.
 
 Note: Fine grain locking implicitly enables [build-dir-new-layout](#build-dir-new-layout) as fine grain locking builds on that directory reoganization.
 
-## `[lints.cargo]`
-
-* Tracking Issue: [#12235](https://github.com/rust-lang/cargo/issues/12235)
-
-A new `lints` tool table for `cargo` that can be used to configure lints emitted
-by `cargo` itself when `-Zcargo-lints` is used
-```toml
-[lints.cargo]
-implicit-features = "warn"
-```
-
-This will work with
-[RFC 2906 `workspace-deduplicate`](https://rust-lang.github.io/rfcs/2906-cargo-workspace-deduplicate.html):
-```toml
-[workspace.lints.cargo]
-implicit-features = "warn"
-
-[lints]
-workspace = true
-```
-
 ## Path Bases
 
 * Tracking Issue: [#14355](https://github.com/rust-lang/cargo/issues/14355)
@@ -2497,3 +2475,9 @@ Support for `resolver.lockfile-path` config field has been stabilized in Rust 1.
 ## warnings
 
 The `build.warnings` config field has been stabilized in Rust 1.97.
+
+## `[lints.cargo]`
+
+Cargo's linting system and the `[lints.cargo]` table have been stabilized in Rust 1.99.
+See the [lints chapter](lints.md) and [the lints section](manifest.md#the-lints-section)
+for information about configuring Cargo lints.

src/compiler/job_queue/mod.rs

@@ -841,15 +841,13 @@ impl<'gctx> DrainState<'gctx> {
         }
         self.progress.clear();
 
-        if build_runner.bcx.gctx.cli_unstable().cargo_lints {
-            let mut global_stats = GlobalDiagnosticStats::new();
-            drop(unused_dependencies::lint_build_results(
-                build_runner,
-                &mut global_stats,
-            ));
-            errors.count += global_stats.error_count();
-            build_runner.compilation.lint_warning_count += global_stats.lint_warning_count();
-        }
+        let mut global_stats = GlobalDiagnosticStats::new();
+        drop(unused_dependencies::lint_build_results(
+            build_runner,
+            &mut global_stats,
+        ));
+        errors.count += global_stats.error_count();
+        build_runner.compilation.lint_warning_count += global_stats.lint_warning_count();
 
         let profile_name = build_runner.bcx.build_config.requested_profile;
         // NOTE: this may be a bit inaccurate, since this may not display the

src/compiler/mod.rs

@@ -852,11 +852,9 @@ fn prepare_rustc(build_runner: &BuildRunner<'_, '_>, unit: &Unit) -> CargoResult
         base.env("CARGO_TARGET_TMPDIR", tmp.display().to_string());
     }
 
-    if build_runner.bcx.gctx.cli_unstable().cargo_lints {
-        // Added last to reduce the risk of RUSTFLAGS or `[lints]` from interfering with
-        // `unused_dependencies` tracking
-        base.arg("--force-warn=unused_crate_dependencies");
-    }
+    // Added last to reduce the risk of RUSTFLAGS or `[lints]` from interfering with
+    // `unused_dependencies` tracking
+    base.arg("--force-warn=unused_crate_dependencies");
 
     Ok(base)
 }
@@ -1230,10 +1228,9 @@ fn add_error_format_and_color(build_runner: &BuildRunner<'_, '_>, cmd: &mut Proc
 
     cmd.arg("--error-format=json");
 
-    let mut json = String::from("--json=diagnostic-rendered-ansi,artifacts,future-incompat");
-    if build_runner.bcx.gctx.cli_unstable().cargo_lints {
-        json.push_str(",unused-externs-silent");
-    }
+    let mut json = String::from(
+        "--json=diagnostic-rendered-ansi,artifacts,future-incompat,unused-externs-silent",
+    );
     if let MessageFormat::Short | MessageFormat::Json { short: true, .. } =
         build_runner.bcx.build_config.message_format
     {

src/diagnostics/passes.rs

@@ -153,44 +153,40 @@ fn emit_parse_pkg_diagnostics(
                 rule(workspace, manifest, &path, &mut pkg_stats, workspace.gctx())?;
             }
             ParsePassRule::LintManifest { rule, lint } => {
-                if workspace.gctx().cli_unstable().cargo_lints {
-                    let manifest: ManifestFor<'_> = pkg.into();
-                    let level = manifest.lint_level(&cargo_lints, lint, workspace.gctx());
-                    if level.level != LintLevel::Allow {
-                        rule(
-                            workspace,
-                            manifest,
-                            &path,
-                            level,
-                            &mut pkg_stats,
-                            workspace.gctx(),
-                        )?;
-                    }
+                let manifest: ManifestFor<'_> = pkg.into();
+                let level = manifest.lint_level(&cargo_lints, lint, workspace.gctx());
+                if level.level != LintLevel::Allow {
+                    rule(
+                        workspace,
+                        manifest,
+                        &path,
+                        level,
+                        &mut pkg_stats,
+                        workspace.gctx(),
+                    )?;
                 }
             }
             ParsePassRule::DiagnosticWorkspace { .. } | ParsePassRule::LintWorkspace { .. } => {}
             ParsePassRule::DiagnosticPackage { rule } => {
                 rule(workspace, pkg, &path, &mut pkg_stats, workspace.gctx())?;
             }
             ParsePassRule::LintPackage { rule, lint } => {
-                if workspace.gctx().cli_unstable().cargo_lints {
-                    let level = lint.level(
-                        &cargo_lints,
-                        pkg.rust_version(),
-                        pkg.manifest().unstable_features(),
-                        workspace.gctx(),
-                    );
+                let level = lint.level(
+                    &cargo_lints,
+                    pkg.rust_version(),
+                    pkg.manifest().unstable_features(),
+                    workspace.gctx(),
+                );
 
-                    if level.level != LintLevel::Allow {
-                        rule(
-                            workspace,
-                            pkg,
-                            &path,
-                            level,
-                            &mut pkg_stats,
-                            workspace.gctx(),
-                        )?;
-                    }
+                if level.level != LintLevel::Allow {
+                    rule(
+                        workspace,
+                        pkg,
+                        &path,
+                        level,
+                        &mut pkg_stats,
+                        workspace.gctx(),
+                    )?;
                 }
             }
         }
@@ -242,19 +238,17 @@ fn emit_parse_ws_diagnostics(
                 )?;
             }
             ParsePassRule::LintManifest { rule, lint } => {
-                if workspace.gctx().cli_unstable().cargo_lints {
-                    let manifest: ManifestFor<'_> = (workspace, workspace.root_maybe()).into();
-                    let level = manifest.lint_level(&cargo_lints, lint, workspace.gctx());
-                    if level.level != LintLevel::Allow {
-                        rule(
-                            workspace,
-                            manifest,
-                            workspace.root_manifest(),
-                            level,
-                            &mut pkg_stats,
-                            workspace.gctx(),
-                        )?;
-                    }
+                let manifest: ManifestFor<'_> = (workspace, workspace.root_maybe()).into();
+                let level = manifest.lint_level(&cargo_lints, lint, workspace.gctx());
+                if level.level != LintLevel::Allow {
+                    rule(
+                        workspace,
+                        manifest,
+                        workspace.root_manifest(),
+                        level,
+                        &mut pkg_stats,
+                        workspace.gctx(),
+                    )?;
                 }
             }
             ParsePassRule::DiagnosticWorkspace { rule } => {
@@ -267,23 +261,21 @@ fn emit_parse_ws_diagnostics(
                 )?;
             }
             ParsePassRule::LintWorkspace { rule, lint } => {
-                if workspace.gctx().cli_unstable().cargo_lints {
-                    let level = lint.level(
-                        &cargo_lints,
-                        workspace.lowest_rust_version(),
-                        workspace.root_maybe().unstable_features(),
+                let level = lint.level(
+                    &cargo_lints,
+                    workspace.lowest_rust_version(),
+                    workspace.root_maybe().unstable_features(),
+                    workspace.gctx(),
+                );
+                if level.level != LintLevel::Allow {
+                    rule(
+                        workspace,
+                        workspace.root_maybe(),
+                        workspace.root_manifest(),
+                        level,
+                        &mut pkg_stats,
                         workspace.gctx(),
-                    );
-                    if level.level != LintLevel::Allow {
-                        rule(
-                            workspace,
-                            workspace.root_maybe(),
-                            workspace.root_manifest(),
-                            level,
-                            &mut pkg_stats,
-                            workspace.gctx(),
-                        )?;
-                    }
+                    )?;
                 }
             }
             ParsePassRule::DiagnosticPackage { .. } | ParsePassRule::LintPackage { .. } => {}

src/workspace/features.rs

@@ -890,7 +890,6 @@ unstable_cli_options!(
     build_std: Option<Vec<String>>  = ("Enable Cargo to compile the standard library itself as part of a crate graph compilation"),
     #[serde(deserialize_with = "deserialize_comma_separated_list")]
     build_std_features: Option<Vec<String>>  = ("Configure features enabled for the standard library itself when building the standard library"),
-    cargo_lints: bool = ("Enable the `[lints.cargo]` table"),
     checksum_freshness: bool = ("Use a checksum to determine if output is fresh rather than filesystem mtime"),
     codegen_backend: bool = ("Enable the `codegen-backend` option in profiles in .cargo/config.toml file"),
     direct_minimal_versions: bool = ("Resolve minimal dependency versions instead of maximum (direct dependencies only)"),
@@ -1007,6 +1006,8 @@ const STABILIZED_REGISTRY_AUTH: &str =
 
 const STABILIZED_LINTS: &str = "The `[lints]` table is now always available.";
 
+const STABILIZED_CARGO_LINTS: &str = "The `[lints.cargo]` table is now always available.";
+
 const STABILIZED_CHECK_CFG: &str =
     "Compile-time checking of conditional (a.k.a. `-Zcheck-cfg`) is now always enabled.";
 
@@ -1423,6 +1424,7 @@ impl CliUnstable {
             "config-include" => stabilized_warn(k, "1.93", STABILIZED_CONFIG_INCLUDE),
             "lockfile-path" => stabilized_warn(k, "1.97", STABILIZED_LOCKFILE_PATH),
             "warnings" => stabilized_warn(k, "1.97", STABILIZED_WARNINGS),
+            "cargo-lints" => stabilized_warn(k, "1.99", STABILIZED_CARGO_LINTS),
 
             // Unstable features
             // Sorted alphabetically:
@@ -1436,7 +1438,6 @@ impl CliUnstable {
             "build-dir-new-layout" => self.build_dir_new_layout = parse_empty(k, v)?,
             "build-std" => self.build_std = Some(parse_list(v)),
             "build-std-features" => self.build_std_features = Some(parse_list(v)),
-            "cargo-lints" => self.cargo_lints = parse_empty(k, v)?,
             "codegen-backend" => self.codegen_backend = parse_empty(k, v)?,
             "direct-minimal-versions" => self.direct_minimal_versions = parse_empty(k, v)?,
             "dual-proc-macros" => self.dual_proc_macros = parse_empty(k, v)?,