Change an assert to a warn
Change an assert to a warn

This is in the constraint simplifier which I'm about
to rewrite, so I'm hoping the assert isn't fatal!

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