From c63d28b39ba1e0fa81ba7e52fefebdc2ad5cfbde Mon Sep 17 00:00:00 2001
From: Joey Hess <joeyh@joeyh.name>
Date: Wed, 12 Sep 2018 14:10:08 -0400
Subject: [PATCH] fix build with older ghc

null only used to work on lists, not sets.

Fixes the Android build and probably also i386ancient.

This commit was sponsored by mo on Patreon.
---
 Annex/Branch/Transitions.hs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/Annex/Branch/Transitions.hs b/Annex/Branch/Transitions.hs
index d682c8fd13..c2283f3866 100644
--- a/Annex/Branch/Transitions.hs
+++ b/Annex/Branch/Transitions.hs
@@ -21,6 +21,7 @@ import Types.UUID
 import Types.MetaData
 
 import qualified Data.Map as M
+import qualified Data.Set as S
 import Data.Default
 
 data FileTransition
@@ -53,7 +54,7 @@ dropDead f content trustmap = case getLogVariety f of
 			else ChangeFile $ Presence.showLog newlog
 	Just RemoteMetaDataLog ->
 		let newlog = dropDeadFromRemoteMetaDataLog trustmap $ MetaData.simplifyLog $ MetaData.parseLog content
-		in if null newlog
+		in if S.null newlog
 			then RemoveFile
 			else ChangeFile $ MetaData.showLog newlog
 	Just OtherLog -> PreserveFile