diff --git a/ghc/driver/ghc.lprl b/ghc/driver/ghc.lprl
index c9a35f7338ad8ed4b8ed3d997a16775f536b4a39..e8c7154c0c244f43b42ab8e0c2ff5a71e8da24f4 100644
--- a/ghc/driver/ghc.lprl
+++ b/ghc/driver/ghc.lprl
@@ -698,6 +698,7 @@ sub setupOptimiseFlags {
 	  '-ffloat-lets-exposing-whnf',
 	  '-ffloat-primops-ok',
 	  '-fcase-of-case',
+	  '-fdo-case-elim',
 #	  '-fdo-lambda-eta-expansion',	# too complicated
 	  '-freuse-con',
 #	  '-flet-to-case',		# no strictness analysis, so...