diff --git a/src/vim9script.c b/src/vim9script.c
index 6d02be6..549c20f 100644
--- a/src/vim9script.c
+++ b/src/vim9script.c
@@ -133,7 +133,8 @@
     si->sn_state = SN_STATE_HAD_COMMAND;
 
     // Store the prefix with the script.  It isused to find exported functions.
-    si->sn_autoload_prefix = get_autoload_prefix(si);
+    if (si->sn_autoload_prefix == NULL)
+	si->sn_autoload_prefix = get_autoload_prefix(si);
 
     current_sctx.sc_version = SCRIPT_VERSION_VIM9;
     si->sn_version = SCRIPT_VERSION_VIM9;