diff --git a/src/testdir/test_cmdline.vim b/src/testdir/test_cmdline.vim
index b2beb68..05beb45 100644
--- a/src/testdir/test_cmdline.vim
+++ b/src/testdir/test_cmdline.vim
@@ -289,13 +289,24 @@
   call assert_equal('"def', @:)
 endfunc
 
-func Test_illegal_address()
+func Test_illegal_address1()
   new
   2;'(
   2;')
   quit
 endfunc
 
+func Test_illegal_address2()
+  call writefile(['c', 'x', '  x', '.', '1;y'], 'Xtest.vim')
+  new
+  source Xtest.vim
+  " Trigger calling validate_cursor()
+  diffsp Xtest.vim
+  quit!
+  bwipe!
+  call delete('Xtest.vim')
+endfunc
+
 func Test_cmdline_complete_wildoptions()
   help
   call feedkeys(":tag /\<c-a>\<c-b>\"\<cr>", 'tx')