Ensure CleanTools is run for check rustdoc

src/bootstrap/builder.rs

@@ -310,7 +310,8 @@ impl<'a> Builder<'a> {
                 tool::Compiletest, tool::RemoteTestServer, tool::RemoteTestClient,
                 tool::RustInstaller, tool::Cargo, tool::Rls, tool::Rustdoc, tool::Clippy,
                 native::Llvm, tool::Rustfmt, tool::Miri, native::Lld),
-            Kind::Check => describe!(check::Std, check::Test, check::Rustc, check::CodegenBackend, check::Rustdoc),
+            Kind::Check => describe!(check::Std, check::Test, check::Rustc, check::CodegenBackend,
+                check::Rustdoc),
             Kind::Test => describe!(test::Tidy, test::Bootstrap, test::Ui, test::RunPass,
                 test::CompileFail, test::ParseFail, test::RunFail, test::RunPassValgrind,
                 test::MirOpt, test::Codegen, test::CodegenUnits, test::Incremental, test::Debuginfo,

src/bootstrap/check.rs

@@ -12,7 +12,7 @@
 
 use compile::{run_cargo, std_cargo, test_cargo, rustc_cargo, rustc_cargo_env, add_to_sysroot};
 use builder::{RunConfig, Builder, ShouldRun, Step};
-use tool::prepare_tool_cargo;
+use tool::{self, prepare_tool_cargo};
 use {Compiler, Mode};
 use cache::{INTERNER, Interned};
 use std::path::PathBuf;
@@ -232,6 +232,12 @@ impl Step for Rustdoc {
 
         let libdir = builder.sysroot_libdir(compiler, target);
         add_to_sysroot(&builder, &libdir, &rustdoc_stamp(builder, compiler, target));
+
+        builder.ensure(tool::CleanTools {
+            compiler,
+            target,
+            mode: Mode::Tool,
+        });
     }
 }