diff --git a/src/testdir/test_reltime.vim b/src/testdir/test_reltime.vim
index c76d7a1..2f2e7ae 100644
--- a/src/testdir/test_reltime.vim
+++ b/src/testdir/test_reltime.vim
@@ -5,6 +5,7 @@
 CheckFeature float
 
 func Test_reltime()
+  let g:test_is_flaky = 1
   let now = reltime()
   sleep 10m
   let later = reltime()