X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcMType.lhs;h=74533340f3b846a68cb5d82ae0606f8447675782;hb=191292aaa7f56f32fc546478f43aa89ac67c95a3;hp=9d74ff894a09bb7463696fd526b1be69fc4cbef4;hpb=d1796b5266121ff6930d6cabba6201e48708703b;p=ghc-hetmet.git

diff --git a/compiler/typecheck/TcMType.lhs b/compiler/typecheck/TcMType.lhs
index 9d74ff8..7453334 100644
--- a/compiler/typecheck/TcMType.lhs
+++ b/compiler/typecheck/TcMType.lhs
@@ -364,8 +364,8 @@ writeMetaTyVarRef tyvar ref ty
 
   | otherwise
   = do { meta_details <- readMutVar ref; 
-       ; WARN( not (isFlexi meta_details), 
-                hang (text "Double update of meta tyvar")
+       ; ASSERT2( isFlexi meta_details, 
+                  hang (text "Double update of meta tyvar")
                    2 (ppr tyvar $$ ppr meta_details) )
 
          traceTc "writeMetaTyVar" (ppr tyvar <+> text ":=" <+> ppr ty)