diff --git a/libraries/gen_contents_index b/libraries/gen_contents_index
index 27fa3c73dff11d0f9f5caa0d346c61c3c73172db..29be2e13f9faf2273c6e57c9eb484d385c6cda1d 100644
--- a/libraries/gen_contents_index
+++ b/libraries/gen_contents_index
@@ -33,7 +33,8 @@ then
     cd dist-haddock
 
     HADDOCK=../../inplace/bin/haddock
-    HADDOCK_FILES=`find ../ -name *.haddock | sort`
+    # Exclude Cabal package-tests, which may run haddock
+    HADDOCK_FILES=`find ../ -name *.haddock | grep -v 'PackageTests' | sort`
     HADDOCK_ARGS="-p ../prologue.txt"
     for HADDOCK_FILE in $HADDOCK_FILES
     do