diff --git a/util/process_wrapper/rustc.rs b/util/process_wrapper/rustc.rs
index ddb82c9..69052ce 100644
--- a/util/process_wrapper/rustc.rs
+++ b/util/process_wrapper/rustc.rs
@@ -64,10 +64,12 @@ pub(crate) fn process_json(line: String, error_format: ErrorFormat) -> LineResult {
     let parsed: JsonValue = line
         .parse()
         .map_err(|_| "error parsing rustc output as json".to_owned())?;
     Ok(match parsed.try_into() {
+        Ok(RustcMessage::Emit(emit)) if emit == "metadata" => LineOutput::Terminate,
+        Ok(RustcMessage::Emit(_)) => LineOutput::Skip,
         Ok(RustcMessage::Message(rendered)) => {
             output_based_on_error_format(line, rendered, error_format)
         }
-        _ => LineOutput::Skip,
+        Err(()) => LineOutput::Skip,
     })
 }