X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Ftypes%2FGenerics.lhs;h=01632d35963183999354deabdd5177da9ec533db;hp=c0fb4fc097340642ed9271926eb8671afcf85f83;hb=66579ff945831c5fc9a17c58c722ff01f2268d76;hpb=766b34f81d81d009f1070e297756423fbadbd421

diff --git a/compiler/types/Generics.lhs b/compiler/types/Generics.lhs
index c0fb4fc..01632d3 100644
--- a/compiler/types/Generics.lhs
+++ b/compiler/types/Generics.lhs
@@ -398,7 +398,7 @@ mkGenericNames tycon
   where
     tc_name  = tyConName tycon
     tc_occ   = nameOccName tc_name
-    tc_mod   = nameModule tc_name
+    tc_mod   = ASSERT( isExternalName tc_name ) nameModule tc_name
     from_RDR = mkOrig tc_mod (mkGenOcc1 tc_occ)
     to_RDR   = mkOrig tc_mod (mkGenOcc2 tc_occ)
 \end{code}