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Author: Kobzol

src/bootstrap/src/core/builder/mod.rs

@@ -186,6 +186,8 @@ impl StepMetadata {
     pub fn get_stage(&self) -> Option<u32> {
         self.stage.or(self
             .built_by
+            // For std, its stage corresponds to the stage of the compiler that builds it.
+            // For everything else, a stage N things gets built by a stage N-1 compiler.
             .map(|compiler| if self.name == "std" { compiler.stage } else { compiler.stage + 1 }))
     }
 }

src/bootstrap/src/core/builder/tests.rs

@@ -1667,8 +1667,7 @@ fn render_metadata(metadata: &StepMetadata) -> String {
     if let Some(compiler) = metadata.built_by {
         write!(record, "{} -> ", render_compiler(compiler));
     }
-    let stage =
-        if let Some(stage) = metadata.get_stage() { format!("{stage} ") } else { "".to_string() };
+    let stage = metadata.get_stage().map(|stage| format!("{stage} ")).unwrap_or_default();
     write!(record, "{} {stage}<{}>", metadata.name, normalize_target(metadata.target));
     record
 }