diff --git a/tools/generate-operator-out.py b/tools/generate-operator-out.py
index 23d6d3e..88753b5 100755
--- a/tools/generate-operator-out.py
+++ b/tools/generate-operator-out.py
@@ -104,7 +104,7 @@
       continue
 
     # Strip // comments.
-    line = re.sub(r'//.*', '', raw_line)
+    line = re.sub(r'^ *//.*', '', raw_line)
 
     # Strip whitespace.
     line = line.strip()