diff --git a/src/testdir/test_quickfix.vim b/src/testdir/test_quickfix.vim
index e56c8a2..3908ce0 100644
--- a/src/testdir/test_quickfix.vim
+++ b/src/testdir/test_quickfix.vim
@@ -684,6 +684,11 @@
   helpgr quickfix
   call setqflist([], 'r')
   cad
-  call assert_fails('cn', 'E553:')
+  try
+    cn
+  catch
+    " number of matches is unknown
+    call assert_true(v:exception =~ 'E553:')
+  endtry
   quit!
 endfunc