diff --git a/src/pl/plperl/expected/plperl_env.out b/src/pl/plperl/expected/plperl_env.out
index 328a536342..f777c072b5 100644
--- a/src/pl/plperl/expected/plperl_env.out
+++ b/src/pl/plperl/expected/plperl_env.out
@@ -51,3 +51,5 @@ $$
 $$ LANGUAGE plperl;
 WARNING:  attempted alteration of $ENV{TEST_PLPERL_ENV_FOO} at line 12.
 NOTICE:  environ unaffected
+-- clean up to simplify cross-version upgrade testing
+DROP FUNCTION get_environ();
diff --git a/src/pl/plperl/sql/plperl_env.sql b/src/pl/plperl/sql/plperl_env.sql
index 4108f392d1..fa5f04146c 100644
--- a/src/pl/plperl/sql/plperl_env.sql
+++ b/src/pl/plperl/sql/plperl_env.sql
@@ -56,3 +56,6 @@ $$
    }
 
 $$ LANGUAGE plperl;
+
+-- clean up to simplify cross-version upgrade testing
+DROP FUNCTION get_environ();