bootstrap: Split the Step trait into multiple traits

src/bootstrap/src/core/build_steps/check.rs

@@ -13,7 +13,8 @@ use crate::core::build_steps::tool::{
     prepare_tool_cargo,
 };
 use crate::core::builder::{
-    self, Alias, Builder, Cargo, Kind, RunConfig, ShouldRun, Step, StepMetadata, crate_description,
+    self, Alias, Builder, Cargo, CommandLineStep, Kind, RunConfig, ShouldRun, Step, StepMetadata,
+    crate_description,
 };
 use crate::core::config::TargetSelection;
 use crate::utils::build_stamp::{self, BuildStamp};
@@ -36,7 +37,7 @@ impl Std {
     const CRATE_OR_DEPS: &[&str] = &["sysroot", "coretests", "alloctests"];
 }
 
-impl Step for Std {
+impl CommandLineStep for Std {
     type Output = BuildStamp;
 
     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
@@ -222,10 +223,6 @@ impl PrepareRustcRmetaSysroot {
 impl Step for PrepareRustcRmetaSysroot {
     type Output = RmetaSysroot;
 
-    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
-        run.never()
-    }
-
     fn run(self, builder: &Builder<'_>) -> Self::Output {
         // Check rustc
         let stamp = builder.ensure(Rustc::from_build_compiler(
@@ -266,10 +263,6 @@ impl PrepareStdRmetaSysroot {
 impl Step for PrepareStdRmetaSysroot {
     type Output = RmetaSysroot;
 
-    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
-        run.never()
-    }
-
     fn run(self, builder: &Builder<'_>) -> Self::Output {
         // Check std
         let stamp = builder.ensure(Std {
@@ -317,7 +310,7 @@ impl Rustc {
     }
 }
 
-impl Step for Rustc {
+impl CommandLineStep for Rustc {
     type Output = BuildStamp;
     const IS_HOST: bool = true;
 
@@ -528,7 +521,7 @@ pub struct CraneliftCodegenBackend {
     target: TargetSelection,
 }
 
-impl Step for CraneliftCodegenBackend {
+impl CommandLineStep for CraneliftCodegenBackend {
     type Output = ();
     const IS_HOST: bool = true;
 
@@ -607,7 +600,7 @@ pub struct GccCodegenBackend {
     target: TargetSelection,
 }
 
-impl Step for GccCodegenBackend {
+impl CommandLineStep for GccCodegenBackend {
     type Output = ();
     const IS_HOST: bool = true;
 
@@ -701,7 +694,7 @@ macro_rules! tool_check_step {
             target: TargetSelection,
         }
 
-        impl Step for $name {
+        impl CommandLineStep for $name {
             type Output = ();
             const IS_HOST: bool = true;
 

src/bootstrap/src/core/build_steps/clean.rs

@@ -9,20 +9,21 @@ use std::fs;
 use std::io::{self, ErrorKind};
 use std::path::Path;
 
-use crate::core::builder::{Builder, RunConfig, ShouldRun, Step, crate_description};
+use crate::core::builder::{Builder, CommandLineStep, RunConfig, ShouldRun, crate_description};
 use crate::utils::build_stamp::BuildStamp;
 use crate::utils::helpers::t;
 use crate::{Build, Compiler, Kind, Mode, Subcommand};
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct CleanAll {}
 
-impl Step for CleanAll {
+impl CommandLineStep for CleanAll {
     type Output = ();
 
     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
-        // Only runs as the default `./x clean` step; cannot be selected explicitly.
-        run.never()
+        // Normally this step is invoked implicitly via `./x clean`, but all
+        // steps are required to register at least one explicit path/alias.
+        run.alias("default")
     }
 
     fn is_default_step(_builder: &Builder<'_>) -> bool {
@@ -54,7 +55,7 @@ macro_rules! clean_crate_tree {
             crates: Vec<String>,
         }
 
-        impl Step for $name {
+        impl CommandLineStep for $name {
             type Output = ();
 
             fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {

src/bootstrap/src/core/build_steps/clippy.rs

@@ -20,7 +20,9 @@ use crate::core::build_steps::compile::{
     ArtifactKeepMode, run_cargo, rustc_cargo, std_cargo, std_crates_for_make_run,
 };
 use crate::core::builder;
-use crate::core::builder::{Alias, Kind, RunConfig, Step, StepMetadata, crate_description};
+use crate::core::builder::{
+    Alias, CommandLineStep, Kind, RunConfig, StepMetadata, crate_description,
+};
 use crate::utils::build_stamp::{self, BuildStamp};
 use crate::{Compiler, Mode, Subcommand, TargetSelection, exit};
 
@@ -167,7 +169,7 @@ impl Std {
     }
 }
 
-impl Step for Std {
+impl CommandLineStep for Std {
     type Output = ();
 
     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
@@ -251,7 +253,7 @@ impl Rustc {
     }
 }
 
-impl Step for Rustc {
+impl CommandLineStep for Rustc {
     type Output = ();
     const IS_HOST: bool = true;
 
@@ -336,7 +338,7 @@ impl CodegenGcc {
     }
 }
 
-impl Step for CodegenGcc {
+impl CommandLineStep for CodegenGcc {
     type Output = ();
 
     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
@@ -422,7 +424,7 @@ macro_rules! lint_any {
             config: LintConfig,
         }
 
-        impl Step for $name {
+        impl CommandLineStep for $name {
             type Output = ();
 
             fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
@@ -522,7 +524,7 @@ pub struct CI {
     config: LintConfig,
 }
 
-impl Step for CI {
+impl CommandLineStep for CI {
     type Output = ();
 
     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {

src/bootstrap/src/core/build_steps/compile.rs

@@ -22,9 +22,9 @@ use tracing::span;
 use crate::core::build_steps::gcc::{Gcc, GccOutput, GccTargetPair};
 use crate::core::build_steps::tool::{RustcPrivateCompilers, SourceType, copy_lld_artifacts};
 use crate::core::build_steps::{dist, llvm};
-use crate::core::builder;
 use crate::core::builder::{
-    Builder, Cargo, Kind, RunConfig, ShouldRun, Step, StepMetadata, apply_pgo, crate_description,
+    self, Builder, Cargo, CommandLineStep, Kind, RunConfig, ShouldRun, Step, StepMetadata,
+    apply_pgo, crate_description,
 };
 use crate::core::config::toml::target::DefaultLinuxLinkerOverride;
 use crate::core::config::{
@@ -109,7 +109,7 @@ impl Std {
     }
 }
 
-impl Step for Std {
+impl CommandLineStep for Std {
     /// Build stamp of std, if it was indeed built or uplifted.
     type Output = Option<BuildStamp>;
 
@@ -743,10 +743,6 @@ impl StdLink {
 impl Step for StdLink {
     type Output = ();
 
-    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
-        run.never()
-    }
-
     /// Link all libstd rlibs/dylibs into the sysroot location.
     ///
     /// Links those artifacts generated by `compiler` to the `stage` compiler's
@@ -900,7 +896,7 @@ pub struct StartupObjects {
     pub target: TargetSelection,
 }
 
-impl Step for StartupObjects {
+impl CommandLineStep for StartupObjects {
     type Output = Vec<(PathBuf, DependencyType)>;
 
     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
@@ -1013,7 +1009,7 @@ impl Rustc {
     }
 }
 
-impl Step for Rustc {
+impl CommandLineStep for Rustc {
     type Output = BuiltRustc;
     const IS_HOST: bool = true;
 
@@ -1535,10 +1531,6 @@ impl RustcLink {
 impl Step for RustcLink {
     type Output = ();
 
-    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
-        run.never()
-    }
-
     /// Same as `StdLink`, only for librustc
     fn run(self, builder: &Builder<'_>) {
         let build_compiler = self.build_compiler;
@@ -1659,7 +1651,7 @@ impl GccCodegenBackend {
     }
 }
 
-impl Step for GccCodegenBackend {
+impl CommandLineStep for GccCodegenBackend {
     type Output = GccCodegenBackendOutput;
 
     const IS_HOST: bool = true;
@@ -1728,7 +1720,7 @@ pub struct CraneliftCodegenBackend {
     pub compilers: RustcPrivateCompilers,
 }
 
-impl Step for CraneliftCodegenBackend {
+impl CommandLineStep for CraneliftCodegenBackend {
     type Output = BuildStamp;
     const IS_HOST: bool = true;
 
@@ -1909,10 +1901,6 @@ impl Sysroot {
 impl Step for Sysroot {
     type Output = PathBuf;
 
-    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
-        run.never()
-    }
-
     /// Returns the sysroot that `compiler` is supposed to use.
     /// For the stage0 compiler, this is stage0-sysroot (because of the initial std build).
     /// For all other stages, it's the same stage directory that the compiler lives in.
@@ -2078,7 +2066,7 @@ pub struct Assemble {
     pub target_compiler: Compiler,
 }
 
-impl Step for Assemble {
+impl CommandLineStep for Assemble {
     type Output = Compiler;
     const IS_HOST: bool = true;