Add ToolTarget to bootstrap

src/bootstrap/README.md

@@ -105,7 +105,7 @@ build/
       debuginfo/
       ...
 
-    # Bootstrap host tools (which are always compiled with the stage0 compiler)
+    # Host tools (which are always compiled with the stage0 compiler)
     # are stored here.
     bootstrap-tools/
 

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

@@ -4,7 +4,10 @@ use crate::core::build_steps::compile::{
     add_to_sysroot, run_cargo, rustc_cargo, rustc_cargo_env, std_cargo, std_crates_for_run_make,
 };
 use crate::core::build_steps::tool;
-use crate::core::build_steps::tool::{COMPILETEST_ALLOW_FEATURES, SourceType, prepare_tool_cargo};
+use crate::core::build_steps::tool::{
+    COMPILETEST_ALLOW_FEATURES, SourceType, ToolTargetBuildMode, get_tool_target_compiler,
+    prepare_tool_cargo,
+};
 use crate::core::builder::{
     self, Alias, Builder, Kind, RunConfig, ShouldRun, Step, StepMetadata, crate_description,
 };
@@ -247,8 +250,10 @@ fn prepare_compiler_for_check(
     mode: Mode,
 ) -> Compiler {
     let host = builder.host_target;
+
     match mode {
         Mode::ToolBootstrap => builder.compiler(0, host),
+        Mode::ToolTarget => get_tool_target_compiler(builder, ToolTargetBuildMode::Build(target)),
         Mode::ToolStd => {
             // These tools require the local standard library to be checked
             let build_compiler = builder.compiler(builder.top_stage, host);

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

@@ -2286,15 +2286,13 @@ impl Step for Assemble {
         }
 
         // In addition to `rust-lld` also install `wasm-component-ld` when
-        // LLD is enabled. This is a relatively small binary that primarily
-        // delegates to the `rust-lld` binary for linking and then runs
-        // logic to create the final binary. This is used by the
-        // `wasm32-wasip2` target of Rust.
+        // is enabled. This is used by the `wasm32-wasip2` target of Rust.
         if builder.tool_enabled("wasm-component-ld") {
-            let wasm_component = builder.ensure(crate::core::build_steps::tool::WasmComponentLd {
-                compiler: build_compiler,
-                target: target_compiler.host,
-            });
+            let wasm_component =
+                builder.ensure(crate::core::build_steps::tool::WasmComponentLd::for_compiler(
+                    builder,
+                    target_compiler,
+                ));
             builder.copy_link(
                 &wasm_component.tool_path,
                 &libdir_bin.join(wasm_component.tool_path.file_name().unwrap()),

src/bootstrap/src/core/build_steps/test.rs

@@ -2941,7 +2941,8 @@ impl Step for RemoteCopyLibs {
 
         builder.info(&format!("REMOTE copy libs to emulator ({target})"));
 
-        let remote_test_server = builder.ensure(tool::RemoteTestServer { compiler, target });
+        let remote_test_server =
+            builder.ensure(tool::RemoteTestServer { build_compiler: compiler, target });
 
         // Spawn the emulator and wait for it to come online
         let tool = builder.tool_exe(Tool::RemoteTestClient);