diff --git a/test/functional/terminal/tui_spec.lua b/test/functional/terminal/tui_spec.lua
index 59dd3a272d..894b94799d 100644
--- a/test/functional/terminal/tui_spec.lua
+++ b/test/functional/terminal/tui_spec.lua
@@ -1823,7 +1823,7 @@ describe('TUI', function()
     write_file(script_file, [=[
       local ffi = require('ffi')
       ffi.cdef([[int execl(const char *, const char *, ...);]])
-      ffi.C.execl(vim.v.progpath, 'Xargv0nvim', '--clean')
+      ffi.C.execl(vim.v.progpath, 'Xargv0nvim', '--clean', nil)
     ]=])
     finally(function()
       os.remove(script_file)