Rollup merge of #139894 - Kobzol:opt-dist-fixes, r=lqd

Fix `opt-dist` CLI flag and make it work without LLD

Suggested in https://rust-lang.zulipchat.com/#narrow/channel/122651-general/topic/experiment.20with.20.60opt-dist.20local.60.20in.20MSYS2/with/512456991.

r? `@jieyouxu`

Author: matthiaskrgr

src/tools/opt-dist/src/main.rs

@@ -76,7 +76,7 @@ enum EnvironmentCmd {
         rustc_perf_checkout_dir: Option<Utf8PathBuf>,
 
         /// Is LLVM for `rustc` built in shared library mode?
-        #[arg(long, default_value_t = true)]
+        #[arg(long, default_value_t = true, action(clap::ArgAction::Set))]
         llvm_shared: bool,
 
         /// Should BOLT optimization be used? If yes, host LLVM must have BOLT binaries

src/tools/opt-dist/src/utils/mod.rs

@@ -36,7 +36,9 @@ pub fn clear_llvm_files(env: &Environment) -> anyhow::Result<()> {
     // directories ourselves.
     log::info!("Clearing LLVM build files");
     delete_directory(&env.build_artifacts().join("llvm"))?;
-    delete_directory(&env.build_artifacts().join("lld"))?;
+    if env.build_artifacts().join("lld").is_dir() {
+        delete_directory(&env.build_artifacts().join("lld"))?;
+    }
     Ok(())
 }