Minor fix.

Author: lschoe

README.md

@@ -57,4 +57,4 @@ By running `python -m mpyc` instead you even get this REPL with the MPyC runtime
 The file `gen.bat` shows how to generate fresh key material for SSL. To generate SSL key material of your own, first run
 `pip install cryptography`.
 
-Copyright © 2018-2024 Berry Schoenmakers
+Copyright © 2018-2025 Berry Schoenmakers

docs/conf.py

@@ -21,7 +21,7 @@
 # -- Project information -----------------------------------------------------
 
 project = 'MPyC'
-copyright = '2018 - 2024, Berry Schoenmakers'
+copyright = '2018 - 2025, Berry Schoenmakers'
 author = 'Berry Schoenmakers'
 
 # The short X.Y version

mpyc/gfpx.py

@@ -304,6 +304,9 @@ def _mul(cls, a, b):
 
     @classmethod
     def _lshift(cls, a, n):
+        if not a:
+            return []
+
         return [0] * n + a
 
     @classmethod