Fix build with newest version of persistent-template.

This is untested because of rain, also I am operating from truncated
copiler error messages in a bug report that also doesn't mention what the
library version is. Still, it should work.

May break builds with old ghc, in particular DerivingStrategies is
I think fairly new? The pragmas could be ifdefed if necessary. Works with
ghc 8.6.5.

CHANGELOG

@@ -1,3 +1,9 @@
+git-annex (7.20200204) UNRELEASED; urgency=medium
+
+  * Fix build with newest version of persistent-template.
+
+ -- Joey Hess <id@joeyh.name>  Tue, 04 Feb 2020 11:58:22 -0400
+
 git-annex (7.20200202.7) upstream; urgency=medium
 
   * add: --force-annex/--force-git options make it easier to override

Database/ContentIdentifier.hs

@@ -10,6 +10,8 @@
 {-# LANGUAGE MultiParamTypeClasses, GeneralizedNewtypeDeriving #-}
 {-# LANGUAGE RankNTypes #-}
 {-# LANGUAGE UndecidableInstances #-}
+{-# LANGUAGE DerivingStrategies #-}
+{-# LANGUAGE StandaloneDeriving #-}
 
 module Database.ContentIdentifier (
 	ContentIdentifierHandle,

Database/Export.hs

@@ -10,6 +10,8 @@
 {-# LANGUAGE MultiParamTypeClasses, GeneralizedNewtypeDeriving #-}
 {-# LANGUAGE RankNTypes #-}
 {-# LANGUAGE UndecidableInstances #-}
+{-# LANGUAGE DerivingStrategies #-}
+{-# LANGUAGE StandaloneDeriving #-}
 
 module Database.Export (
 	ExportHandle,

Database/Fsck.hs

@@ -10,6 +10,8 @@
 {-# LANGUAGE MultiParamTypeClasses, GeneralizedNewtypeDeriving #-}
 {-# LANGUAGE RankNTypes #-}
 {-# LANGUAGE UndecidableInstances #-}
+{-# LANGUAGE DerivingStrategies #-}
+{-# LANGUAGE StandaloneDeriving #-}
 
 module Database.Fsck (
 	FsckHandle,

Database/Keys/SQL.hs

@@ -10,6 +10,8 @@
 {-# LANGUAGE MultiParamTypeClasses, GeneralizedNewtypeDeriving #-}
 {-# LANGUAGE RankNTypes, ScopedTypeVariables #-}
 {-# LANGUAGE UndecidableInstances #-}
+{-# LANGUAGE DerivingStrategies #-}
+{-# LANGUAGE StandaloneDeriving #-}
 
 module Database.Keys.SQL where
 

doc/bugs/brew_install_git-annex_failed/comment_3_627876a558898bb9f622b80dbacee051._comment

@@ -0,0 +1,8 @@
+[[!comment format=mdwn
+ username="joey"
+ subject="""comment 3"""
+ date="2020-02-04T15:56:00Z"
+ content="""
+I think I've fixed this in master now, but have not been able to test the fix
+yet since I don't have the bandwidth to upgrade.
+"""]]