diff --git a/mk/config.mk.in b/mk/config.mk.in
index 11f3688a95ef1bccfaafc5331d57e78f54b5eb27..50906bd6e29e332aa614d894b7a65df269dfb069 100644
--- a/mk/config.mk.in
+++ b/mk/config.mk.in
@@ -344,10 +344,9 @@ HappyBinDistShScripts = happy
 #	real
 #	parallel
 #	PRIVATE
-#	GHC_ONLY
 #	PENDING
 #	UNUSED
-NoFibSubDirs = imaginary spectral real GHC_ONLY PRIVATE
+NoFibSubDirs = imaginary spectral real PRIVATE
 
 # The different ways to build nofib. Default is just to mirror
 # what is done for the ghc prelude libraries.