diff --git a/src/channel.c b/src/channel.c
index a29414f..31c9bbe 100644
--- a/src/channel.c
+++ b/src/channel.c
@@ -1650,7 +1650,7 @@
     argv[0].v_type = VAR_CHANNEL;
     argv[0].vval.v_channel = channel;
 
-    call_func(callback, (int)STRLEN(callback), &rettv, 2, argv, NULL,
+    call_func(callback, -1, &rettv, 2, argv, NULL,
 					  0L, 0L, &dummy, TRUE, partial, NULL);
     clear_tv(&rettv);
     channel_need_redraw = TRUE;
@@ -2989,7 +2989,7 @@
 						(char *)channel->ch_close_cb);
 	      argv[0].v_type = VAR_CHANNEL;
 	      argv[0].vval.v_channel = channel;
-	      call_func(channel->ch_close_cb, (int)STRLEN(channel->ch_close_cb),
+	      call_func(channel->ch_close_cb, -1,
 			   &rettv, 1, argv, NULL, 0L, 0L, &dummy, TRUE,
 			   channel->ch_close_partial, NULL);
 	      clear_tv(&rettv);
@@ -5478,7 +5478,7 @@
 	argv[0].vval.v_job = job;
 	argv[1].v_type = VAR_NUMBER;
 	argv[1].vval.v_number = job->jv_exitval;
-	call_func(job->jv_exit_cb, (int)STRLEN(job->jv_exit_cb),
+	call_func(job->jv_exit_cb, -1,
 	    &rettv, 2, argv, NULL, 0L, 0L, &dummy, TRUE,
 	    job->jv_exit_partial, NULL);
 	clear_tv(&rettv);
@@ -6069,8 +6069,7 @@
     argv[0].vval.v_string = vim_strsave(text);
     argv[1].v_type = VAR_UNKNOWN;
 
-    call_func(curbuf->b_prompt_callback,
-	      (int)STRLEN(curbuf->b_prompt_callback),
+    call_func(curbuf->b_prompt_callback, -1,
 	      &rettv, 1, argv, NULL, 0L, 0L, &dummy, TRUE,
 	      curbuf->b_prompt_partial, NULL);
     clear_tv(&argv[0]);
@@ -6093,8 +6092,7 @@
     argv[0].v_type = VAR_UNKNOWN;
 
     got_int = FALSE; // don't skip executing commands
-    call_func(curbuf->b_prompt_interrupt,
-	      (int)STRLEN(curbuf->b_prompt_interrupt),
+    call_func(curbuf->b_prompt_interrupt, -1,
 	      &rettv, 0, argv, NULL, 0L, 0L, &dummy, TRUE,
 	      curbuf->b_prompt_int_partial, NULL);
     clear_tv(&rettv);
diff --git a/src/eval.c b/src/eval.c
index fe8a8ef..7df5455 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -765,7 +765,7 @@
 	s = expr->vval.v_string;
 	if (s == NULL || *s == NUL)
 	    return FAIL;
-	if (call_func(s, (int)STRLEN(s), rettv, argc, argv, NULL,
+	if (call_func(s, -1, rettv, argc, argv, NULL,
 				     0L, 0L, &dummy, TRUE, NULL, NULL) == FAIL)
 	    return FAIL;
     }
@@ -776,7 +776,7 @@
 	s = partial_name(partial);
 	if (s == NULL || *s == NUL)
 	    return FAIL;
-	if (call_func(s, (int)STRLEN(s), rettv, argc, argv, NULL,
+	if (call_func(s, -1, rettv, argc, argv, NULL,
 				  0L, 0L, &dummy, TRUE, partial, NULL) == FAIL)
 	    return FAIL;
     }
@@ -1088,7 +1088,7 @@
     int		ret;
 
     rettv->v_type = VAR_UNKNOWN;		/* clear_tv() uses this */
-    ret = call_func(func, (int)STRLEN(func), rettv, argc, argv, NULL,
+    ret = call_func(func, -1, rettv, argc, argv, NULL,
 		    curwin->w_cursor.lnum, curwin->w_cursor.lnum,
 		    &doesrange, TRUE, NULL, NULL);
     if (ret == FAIL)
@@ -7109,7 +7109,7 @@
 	    }
 	    else
 		s = (char_u *)"";
-	    ret = get_func_tv(s, (int)STRLEN(s), rettv, arg,
+	    ret = get_func_tv(s, -1, rettv, arg,
 			curwin->w_cursor.lnum, curwin->w_cursor.lnum,
 			&len, evaluate, pt, selfdict);
 
diff --git a/src/evalfunc.c b/src/evalfunc.c
index ff51d12..02ca1ae 100644
--- a/src/evalfunc.c
+++ b/src/evalfunc.c
@@ -767,6 +767,8 @@
     {"line2byte",	1, 1, f_line2byte},
     {"lispindent",	1, 1, f_lispindent},
     {"list2str",	1, 2, f_list2str},
+    {"listener_add",	1, 2, f_listener_add},
+    {"listener_remove",	1, 1, f_listener_remove},
     {"localtime",	0, 0, f_localtime},
 #ifdef FEAT_FLOAT
     {"log",		1, 1, f_log},
@@ -9746,9 +9748,9 @@
 
     if (failed)
     {
+	// an empty list is returned on error
 	list_free(rettv->vval.v_list);
-	/* readfile doc says an empty list is returned on error */
-	rettv->vval.v_list = list_alloc();
+	rettv_list_alloc(rettv);
     }
 
     vim_free(prev);
@@ -12644,8 +12646,7 @@
     copy_tv(&si2->item->li_tv, &argv[1]);
 
     rettv.v_type = VAR_UNKNOWN;		/* clear_tv() uses this */
-    res = call_func(func_name, (int)STRLEN(func_name),
-				 &rettv, 2, argv, NULL, 0L, 0L, &dummy, TRUE,
+    res = call_func(func_name, -1, &rettv, 2, argv, NULL, 0L, 0L, &dummy, TRUE,
 				 partial, sortinfo->item_compare_selfdict);
     clear_tv(&argv[0]);
     clear_tv(&argv[1]);
diff --git a/src/ex_cmds2.c b/src/ex_cmds2.c
index 8bab853..18c438c 100644
--- a/src/ex_cmds2.c
+++ b/src/ex_cmds2.c
@@ -325,7 +325,7 @@
     argv[0].vval.v_number = (varnumber_T)timer->tr_id;
     argv[1].v_type = VAR_UNKNOWN;
 
-    call_func(timer->tr_callback, (int)STRLEN(timer->tr_callback),
+    call_func(timer->tr_callback, -1,
 			&rettv, 1, argv, NULL, 0L, 0L, &dummy, TRUE,
 			timer->tr_partial, NULL);
     clear_tv(&rettv);
diff --git a/src/regexp.c b/src/regexp.c
index ceeb899..ee485a3 100644
--- a/src/regexp.c
+++ b/src/regexp.c
@@ -7423,7 +7423,7 @@
 		if (expr->v_type == VAR_FUNC)
 		{
 		    s = expr->vval.v_string;
-		    call_func(s, (int)STRLEN(s), &rettv,
+		    call_func(s, -1, &rettv,
 				    1, argv, fill_submatch_list,
 					 0L, 0L, &dummy, TRUE, NULL, NULL);
 		}
@@ -7432,7 +7432,7 @@
 		    partial_T   *partial = expr->vval.v_partial;
 
 		    s = partial_name(partial);
-		    call_func(s, (int)STRLEN(s), &rettv,
+		    call_func(s, -1, &rettv,
 				    1, argv, fill_submatch_list,
 				      0L, 0L, &dummy, TRUE, partial, NULL);
 		}
diff --git a/src/terminal.c b/src/terminal.c
index f007bf2..bc57d64 100644
--- a/src/terminal.c
+++ b/src/terminal.c
@@ -3779,7 +3779,7 @@
     argvars[0].v_type = VAR_NUMBER;
     argvars[0].vval.v_number = term->tl_buffer->b_fnum;
     argvars[1] = item->li_next->li_tv;
-    if (call_func(func, (int)STRLEN(func), &rettv,
+    if (call_func(func, -1, &rettv,
 		2, argvars, /* argv_func */ NULL,
 		/* firstline */ 1, /* lastline */ 1,
 		&doesrange, /* evaluate */ TRUE,
diff --git a/src/userfunc.c b/src/userfunc.c
index d8cbe63..4959b0d 100644
--- a/src/userfunc.c
+++ b/src/userfunc.c
@@ -432,16 +432,16 @@
  */
     int
 get_func_tv(
-    char_u	*name,		/* name of the function */
-    int		len,		/* length of "name" */
+    char_u	*name,		// name of the function
+    int		len,		// length of "name" or -1 to use strlen()
     typval_T	*rettv,
-    char_u	**arg,		/* argument, pointing to the '(' */
-    linenr_T	firstline,	/* first line of range */
-    linenr_T	lastline,	/* last line of range */
-    int		*doesrange,	/* return: function handled range */
+    char_u	**arg,		// argument, pointing to the '('
+    linenr_T	firstline,	// first line of range
+    linenr_T	lastline,	// last line of range
+    int		*doesrange,	// return: function handled range
     int		evaluate,
-    partial_T	*partial,	/* for extra arguments */
-    dict_T	*selfdict)	/* Dictionary for "self" */
+    partial_T	*partial,	// for extra arguments
+    dict_T	*selfdict)	// Dictionary for "self"
 {
     char_u	*argp;
     int		ret = OK;
@@ -1435,7 +1435,7 @@
     }
 
     if (item == NULL)
-	r = call_func(name, (int)STRLEN(name), rettv, argc, argv, NULL,
+	r = call_func(name, -1, rettv, argc, argv, NULL,
 				 curwin->w_cursor.lnum, curwin->w_cursor.lnum,
 					     &dummy, TRUE, partial, selfdict);
 
@@ -1458,20 +1458,20 @@
  */
     int
 call_func(
-    char_u	*funcname,	/* name of the function */
-    int		len,		/* length of "name" */
-    typval_T	*rettv,		/* return value goes here */
-    int		argcount_in,	/* number of "argvars" */
-    typval_T	*argvars_in,	/* vars for arguments, must have "argcount"
-				   PLUS ONE elements! */
+    char_u	*funcname,	// name of the function
+    int		len,		// length of "name" or -1 to use strlen()
+    typval_T	*rettv,		// return value goes here
+    int		argcount_in,	// number of "argvars"
+    typval_T	*argvars_in,	// vars for arguments, must have "argcount"
+				// PLUS ONE elements!
     int		(* argv_func)(int, typval_T *, int),
-				/* function to fill in argvars */
-    linenr_T	firstline,	/* first line of range */
-    linenr_T	lastline,	/* last line of range */
-    int		*doesrange,	/* return: function handled range */
+				// function to fill in argvars
+    linenr_T	firstline,	// first line of range
+    linenr_T	lastline,	// last line of range
+    int		*doesrange,	// return: function handled range
     int		evaluate,
-    partial_T	*partial,	/* optional, can be NULL */
-    dict_T	*selfdict_in)	/* Dictionary for "self" */
+    partial_T	*partial,	// optional, can be NULL
+    dict_T	*selfdict_in)	// Dictionary for "self"
 {
     int		ret = FAIL;
     int		error = ERROR_NONE;
@@ -1487,9 +1487,9 @@
     typval_T	argv[MAX_FUNC_ARGS + 1]; /* used when "partial" is not NULL */
     int		argv_clear = 0;
 
-    /* Make a copy of the name, if it comes from a funcref variable it could
-     * be changed or deleted in the called function. */
-    name = vim_strnsave(funcname, len);
+    // Make a copy of the name, if it comes from a funcref variable it could
+    // be changed or deleted in the called function.
+    name = len > 0 ? vim_strnsave(funcname, len) : vim_strsave(funcname);
     if (name == NULL)
 	return ret;
 
@@ -3285,7 +3285,7 @@
 	    curwin->w_cursor.coladd = 0;
 	}
 	arg = startarg;
-	if (get_func_tv(name, (int)STRLEN(name), &rettv, &arg,
+	if (get_func_tv(name, -1, &rettv, &arg,
 		    eap->line1, eap->line2, &doesrange,
 				   !eap->skip, partial, fudi.fd_dict) == FAIL)
 	{
diff --git a/src/version.c b/src/version.c
index ea97bef..7bcb8c8 100644
--- a/src/version.c
+++ b/src/version.c
@@ -768,6 +768,10 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1319,
+/**/
+    1318,
+/**/
     1317,
 /**/
     1316,