diff --git a/src/userfunc.c b/src/userfunc.c
index 772d45d..99d4e03 100644
--- a/src/userfunc.c
+++ b/src/userfunc.c
@@ -2188,6 +2188,8 @@
     int		islambda = FALSE;
     char_u	numbuf[NUMBUFLEN];
     char_u	*name;
+    typval_T	*tv_to_free[MAX_FUNC_ARGS];
+    int		tv_to_free_len = 0;
 #ifdef FEAT_PROFILE
     profinfo_T	profile_info;
 #endif
@@ -2333,6 +2335,7 @@
 	    if (isdefault)
 	    {
 		char_u	    *default_expr = NULL;
+
 		def_rettv.v_type = VAR_NUMBER;
 		def_rettv.vval.v_number = -1;
 
@@ -2374,6 +2377,10 @@
 	v->di_tv = isdefault ? def_rettv : argvars[i];
 	v->di_tv.v_lock = VAR_FIXED;
 
+	if (isdefault)
+	    // Need to free this later, no matter where it's stored.
+	    tv_to_free[tv_to_free_len++] = &v->di_tv;
+
 	if (addlocal)
 	{
 	    // Named arguments should be accessed without the "a:" prefix in
@@ -2563,6 +2570,8 @@
 
     did_emsg |= save_did_emsg;
     funcdepth_decrement();
+    for (i = 0; i < tv_to_free_len; ++i)
+	clear_tv(tv_to_free[i]);
     cleanup_function_call(fc);
 }