diff --git a/src/evalfunc.c b/src/evalfunc.c
index 7dd5c2a..3207441 100644
--- a/src/evalfunc.c
+++ b/src/evalfunc.c
@@ -3612,7 +3612,7 @@
 
     if (s == NULL || *s == NUL || (use_string && VIM_ISDIGIT(*s))
 					 || (is_funcref && trans_name == NULL))
-	EMSG2(_(e_invarg2), s);
+	EMSG2(_(e_invarg2), use_string ? get_tv_string(&argvars[0]) : s);
     /* Don't check an autoload name for existence here. */
     else if (trans_name != NULL && (is_funcref
 				? find_func(trans_name) == NULL
diff --git a/src/testdir/test_expr.vim b/src/testdir/test_expr.vim
index 108ee50..dff8e36 100644
--- a/src/testdir/test_expr.vim
+++ b/src/testdir/test_expr.vim
@@ -439,6 +439,9 @@
   let s:fref = function(s:f)
   call assert_equal(v:t_string, s:fref('x'))
   call assert_fails("call function('s:f')", 'E700:')
+
+  call assert_fails("call function('foo()')", 'E475:')
+  call assert_fails("call function('foo()')", 'foo()')
 endfunc
 
 func Test_funcref()
diff --git a/src/version.c b/src/version.c
index dcf02c2..5634114 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    4,
+/**/
     3,
 /**/
     2,