Use a derived Ord instance for Discr
Use a derived Ord instance for Discr

Our hand-written leAlt behaved differently when given a micture of
constructors, but I think that either it won't make a difference or
that this will be an improvement.

AlexanderPankiv/ghc,ezyang/ghc,anton-dessiatov/ghc,forked-upstream-packages-for-ghcjs/ghc,forked-upstream-packages-for-ghcjs/ghc,anton-dessiatov/ghc,snoyberg/ghc,sgillespie/ghc,elieux/ghc,siddhanathan/ghc,lukexi/ghc,vikraman/ghc,siddhanathan/ghc,da-x/ghc,ryantm/ghc,gridaphobe/ghc,siddhanathan/ghc,elieux/ghc,snoyberg/ghc,gcampax/ghc,oldmanmike/ghc,snoyberg/ghc,hferreiro/replay,gcampax/ghc,vTurbine/ghc,spacekitteh/smcghc,anton-dessiatov/ghc,mcschroeder/ghc,oldmanmike/ghc,nathyong/microghc-ghc,nkaretnikov/ghc,oldmanmike/ghc,hferreiro/replay,hferreiro/replay,lukexi/ghc,nkaretnikov/ghc,fmthoma/ghc,da-x/ghc,AlexanderPankiv/ghc,elieux/ghc,mettekou/ghc,ghc-android/ghc,wxwxwwxxx/ghc,olsner/ghc,mettekou/ghc,vTurbine/ghc,nkaretnikov/ghc,fmthoma/ghc,nomeata/ghc,ryantm/ghc,nathyong/microghc-ghc,GaloisInc/halvm-ghc,AlexanderPankiv/ghc,spacekitteh/smcghc,green-haskell/ghc,mettekou/ghc,olsner/ghc,tibbe/ghc,snoyberg/ghc,tibbe/ghc,urbanslug/ghc,nkaretnikov/ghc,forked-upstream-packages-for-ghcjs/ghc,ezyang/ghc,mfine/ghc,sdiehl/ghc,wxwxwwxxx/ghc,snoyberg/ghc,nkaretnikov/ghc,sgillespie/ghc,olsner/ghc,ezyang/ghc,frantisekfarka/ghc-dsi,elieux/ghc,ekmett/ghc,nomeata/ghc,elieux/ghc,gcampax/ghc,gridaphobe/ghc,anton-dessiatov/ghc,shlevy/ghc,ml9951/ghc,bitemyapp/ghc,frantisekfarka/ghc-dsi,ezyang/ghc,mcschroeder/ghc,fmthoma/ghc,sdiehl/ghc,tjakway/ghcjvm,urbanslug/ghc,mfine/ghc,sdiehl/ghc,christiaanb/ghc,ghc-android/ghc,ryantm/ghc,siddhanathan/ghc,spacekitteh/smcghc,gcampax/ghc,olsner/ghc,shlevy/ghc,christiaanb/ghc,mcschroeder/ghc,nathyong/microghc-ghc,holzensp/ghc,vikraman/ghc,siddhanathan/ghc,shlevy/ghc,mettekou/ghc,ml9951/ghc,gridaphobe/ghc,acowley/ghc,ghc-android/ghc,nushio3/ghc,ml9951/ghc,forked-upstream-packages-for-ghcjs/ghc,mfine/ghc,TomMD/ghc,nushio3/ghc,tjakway/ghcjvm,ekmett/ghc,ghc-android/ghc,siddhanathan/ghc,frantisekfarka/ghc-dsi,AlexanderPankiv/ghc,mfine/ghc,GaloisInc/halvm-ghc,lukexi/ghc-7.8-arm64,christiaanb/ghc,AlexanderPankiv/ghc,nkaretnikov/ghc,wxwxwwxxx/ghc,green-haskell/ghc,shlevy/ghc,vikraman/ghc,acowley/ghc,nathyong/microghc-ghc,shlevy/ghc,wxwxwwxxx/ghc,olsner/ghc,olsner/ghc,oldmanmike/ghc,bitemyapp/ghc,vTurbine/ghc,ml9951/ghc,siddhanathan/ghc,sgillespie/ghc,spacekitteh/smcghc,urbanslug/ghc,jstolarek/ghc,ml9951/ghc,tibbe/ghc,acowley/ghc,da-x/ghc,christiaanb/ghc,frantisekfarka/ghc-dsi,forked-upstream-packages-for-ghcjs/ghc,snoyberg/ghc,ezyang/ghc,lukexi/ghc,christiaanb/ghc,vTurbine/ghc,vikraman/ghc,sgillespie/ghc,nushio3/ghc,anton-dessiatov/ghc,anton-dessiatov/ghc,frantisekfarka/ghc-dsi,da-x/ghc,sdiehl/ghc,sdiehl/ghc,nomeata/ghc,wxwxwwxxx/ghc,green-haskell/ghc,tjakway/ghcjvm,nathyong/microghc-ghc,nushio3/ghc,holzensp/ghc,forked-upstream-packages-for-ghcjs/ghc,mcschroeder/ghc,lukexi/ghc-7.8-arm64,hferreiro/replay,vikraman/ghc,olsner/ghc,ezyang/ghc,fmthoma/ghc,forked-upstream-packages-for-ghcjs/ghc,holzensp/ghc,oldmanmike/ghc,urbanslug/ghc,ekmett/ghc,snoyberg/ghc,GaloisInc/halvm-ghc,AlexanderPankiv/ghc,jstolarek/ghc,gridaphobe/ghc,mcschroeder/ghc,jstolarek/ghc,christiaanb/ghc,vikraman/ghc,mfine/ghc,bitemyapp/ghc,TomMD/ghc,green-haskell/ghc,acowley/ghc,vTurbine/ghc,TomMD/ghc,sgillespie/ghc,ghc-android/ghc,ghc-android/ghc,christiaanb/ghc,hferreiro/replay,holzensp/ghc,ezyang/ghc,tjakway/ghcjvm,da-x/ghc,urbanslug/ghc,lukexi/ghc-7.8-arm64,hferreiro/replay,AlexanderPankiv/ghc,GaloisInc/halvm-ghc,ryantm/ghc,ml9951/ghc,lukexi/ghc,fmthoma/ghc,nomeata/ghc,ghc-android/ghc,bitemyapp/ghc,gcampax/ghc,urbanslug/ghc,lukexi/ghc-7.8-arm64,gcampax/ghc,mettekou/ghc,tjakway/ghcjvm,GaloisInc/halvm-ghc,lukexi/ghc-7.8-arm64,oldmanmike/ghc,gcampax/ghc,mettekou/ghc,ryantm/ghc,elieux/ghc,anton-dessiatov/ghc,TomMD/ghc,TomMD/ghc,sdiehl/ghc,shlevy/ghc,sgillespie/ghc,tibbe/ghc,acowley/ghc,holzensp/ghc,tibbe/ghc,nomeata/ghc,nathyong/microghc-ghc,mcschroeder/ghc,green-haskell/ghc,TomMD/ghc,shlevy/ghc,nushio3/ghc,gridaphobe/ghc,lukexi/ghc,TomMD/ghc,elieux/ghc,fmthoma/ghc,gridaphobe/ghc,nkaretnikov/ghc,ekmett/ghc,vTurbine/ghc,urbanslug/ghc,bitemyapp/ghc,da-x/ghc,mfine/ghc,jstolarek/ghc,wxwxwwxxx/ghc,ekmett/ghc,ml9951/ghc,GaloisInc/halvm-ghc,oldmanmike/ghc,mettekou/ghc,fmthoma/ghc,nushio3/ghc,gridaphobe/ghc,sdiehl/ghc,tjakway/ghcjvm,GaloisInc/halvm-ghc,acowley/ghc,da-x/ghc,nushio3/ghc,jstolarek/ghc,vTurbine/ghc,mfine/ghc,vikraman/ghc,spacekitteh/smcghc,ml9951/ghc,nathyong/microghc-ghc,wxwxwwxxx/ghc,tjakway/ghcjvm,mcschroeder/ghc,hferreiro/replay,acowley/ghc,sgillespie/ghc