bootstrap: Make LLD available to run-make tests.

Author: michaelwoerister

src/bootstrap/tool.rs

@@ -1,6 +1,5 @@
 use std::fs;
 use std::env;
-use std::iter;
 use std::path::PathBuf;
 use std::process::{Command, exit};
 use std::collections::HashSet;
@@ -666,27 +665,41 @@ impl<'a> Builder<'a> {
 
         // Add the llvm/bin directory to PATH since it contains lots of
         // useful, platform-independent tools
-        if tool.uses_llvm_tools() {
+        if tool.uses_llvm_tools() && !self.config.dry_run {
+            let mut additional_paths = vec![];
+
             if let Some(llvm_bin_path) = self.llvm_bin_path() {
-                if host.contains("windows") {
-                    // On Windows, PATH and the dynamic library path are the same,
-                    // so we just add the LLVM bin path to lib_path
-                    lib_paths.push(llvm_bin_path);
-                } else {
-                    let old_path = env::var_os("PATH").unwrap_or_default();
-                    let new_path = env::join_paths(iter::once(llvm_bin_path)
-                            .chain(env::split_paths(&old_path)))
-                        .expect("Could not add LLVM bin path to PATH");
-                    cmd.env("PATH", new_path);
-                }
+                additional_paths.push(llvm_bin_path);
+            }
+
+            // If LLD is available, add that too.
+            if self.config.lld_enabled {
+                let lld_install_root = self.ensure(native::Lld {
+                    target: self.config.build,
+                });
+
+                let lld_bin_path = lld_install_root.join("bin");
+                additional_paths.push(lld_bin_path);
+            }
+
+            if host.contains("windows") {
+                // On Windows, PATH and the dynamic library path are the same,
+                // so we just add the LLVM bin path to lib_path
+                lib_paths.extend(additional_paths);
+            } else {
+                let old_path = env::var_os("PATH").unwrap_or_default();
+                let new_path = env::join_paths(additional_paths.into_iter()
+                        .chain(env::split_paths(&old_path)))
+                    .expect("Could not add LLVM bin path to PATH");
+                cmd.env("PATH", new_path);
             }
         }
 
         add_lib_path(lib_paths, cmd);
     }
 
     fn llvm_bin_path(&self) -> Option<PathBuf> {
-        if self.config.llvm_enabled && !self.config.dry_run {
+        if self.config.llvm_enabled {
             let llvm_config = self.ensure(native::Llvm {
                 target: self.config.build,
                 emscripten: false,