diff --git a/src/base.rs b/src/base.rs
index 441d875ef21d4..243852f1d2bef 100644
--- a/src/base.rs
+++ b/src/base.rs
@@ -74,20 +74,22 @@ pub fn trans_fn<'clif, 'tcx, B: Backend + 'static>(
     context.func = func;
     cx.module.define_function(func_id, context).unwrap();
 
-    let value_ranges = context
-        .build_value_labels_ranges(cx.module.isa())
-        .expect("value location ranges");
-
     // Write optimized function to file for debugging
     #[cfg(debug_assertions)]
-    crate::pretty_clif::write_clif_file(
-        cx.tcx,
-        "opt",
-        instance,
-        &context.func,
-        &clif_comments,
-        Some(&value_ranges),
-    );
+    {
+        let value_ranges = context
+            .build_value_labels_ranges(cx.module.isa())
+            .expect("value location ranges");
+
+        crate::pretty_clif::write_clif_file(
+            cx.tcx,
+            "opt",
+            instance,
+            &context.func,
+            &clif_comments,
+            Some(&value_ranges),
+        );
+    }
 
     // Define debuginfo for function
     let isa = cx.module.isa();
diff --git a/src/pretty_clif.rs b/src/pretty_clif.rs
index f595d384f4f2c..64359f3899f53 100644
--- a/src/pretty_clif.rs
+++ b/src/pretty_clif.rs
@@ -74,8 +74,8 @@ pub struct CommentWriter {
 
 impl CommentWriter {
     pub fn new<'tcx>(tcx: TyCtxt<'tcx>, instance: Instance<'tcx>) -> Self {
-        CommentWriter {
-            global_comments: vec![
+        let mut global_comments = if cfg!(debug_assertions) {
+            vec![
                 format!("symbol {}", tcx.symbol_name(instance).name.as_str()),
                 format!("instance {:?}", instance),
                 format!(
@@ -86,7 +86,13 @@ impl CommentWriter {
                     )
                 ),
                 String::new(),
-            ],
+            ]
+        } else {
+            vec![]
+        };
+
+        CommentWriter {
+            global_comments,
             entity_comments: HashMap::new(),
             inst_comments: HashMap::new(),
         }