diff --git a/Lib/codeop.py b/Lib/codeop.py
index 7e192ea..5476292 100644
--- a/Lib/codeop.py
+++ b/Lib/codeop.py
@@ -84,9 +84,11 @@
     except SyntaxError:
         pass
 
-    # Suppress warnings after the first compile to avoid duplication.
+    # Catch syntax warnings after the first compile
+    # to emit SyntaxWarning at most once.
     with warnings.catch_warnings():
-        warnings.simplefilter("ignore")
+        warnings.simplefilter("error", SyntaxWarning)
+
         try:
             code1 = compiler(source + "\n", filename, symbol)
         except SyntaxError as e: