xmonad error

cat ~/.xmonad/xmonad.errors
$ ghc --make xmonad.hs -i -ilib -fforce-recomp -main-is main -dynamic -v0 -outputdir /home/user01/.xmonad/build-x86_64-linux -o /home/user01/.xmonad/xmonad-x86_64-linux

xmonad.hs:33:15: warning: [-Wdeprecations]
    In the use of ‘defaultConfig’
    (imported from XMonad, but defined in XMonad.Config):
    Deprecated: "Use def (from Data.Default, and re-exported by XMonad and XMonad.Config) instead."
   |
33 | main = xmonad defaultConfig
   |               ^^^^^^^^^^^^^