use source std on stage 0 for opt-dist

Signed-off-by: onur-ozkan <[email protected]>

Author: onur-ozkan

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

@@ -109,6 +109,8 @@ impl Bootstrap {
             "--stage",
             "2",
             "library/std",
+            // FIXME: benchmarks fails when using beta std on stage 0
+            "--build-std-on-stage0",
         ])
         .env("RUST_BACKTRACE", "full");
         Self { cmd, metrics_path }
@@ -117,6 +119,10 @@ impl Bootstrap {
     pub fn dist(env: &Environment, dist_args: &[String]) -> Self {
         let metrics_path = env.build_root().join("build").join("metrics.json");
         let cmd = cmd(&dist_args.iter().map(|arg| arg.as_str()).collect::<Vec<_>>())
+            // In this command we have `--keep-stage 0 --keep-stage 1` flags. Since we used
+            // `--build-std-on-stage0` in the previous bootstrap invocation (in `fn build`)
+            // we need to include it again.
+            .arg("--build-std-on-stage0")
             .env("RUST_BACKTRACE", "full");
         Self { cmd, metrics_path }
     }