[project @ 2002-03-26 19:08:19 by simonpj]

Fix readHoleResult bug

diff --git a/ghc/compiler/typecheck/TcPat.lhs b/ghc/compiler/typecheck/TcPat.lhs
index cb08317..ea64699 100644 (file)
--- a/ghc/compiler/typecheck/TcPat.lhs
+++ b/ghc/compiler/typecheck/TcPat.lhs
@@ -139,7 +139,10 @@ tcPat tc_bndr pat_in@(AsPatIn name pat) pat_ty
              tvs, (name, bndr_id) `consBag` ids, lie_avail)
 
 tcPat tc_bndr WildPatIn pat_ty
-  = returnTc (WildPat pat_ty, emptyLIE, emptyBag, emptyBag, emptyLIE)
+  = zapToType pat_ty                   `thenNF_Tc` \ pat_ty' ->
+       -- We might have an incoming 'hole' type variable; no annotation
+       -- so zap it to a type.  Rather like tcMonoPatBndr.
+    returnTc (WildPat pat_ty', emptyLIE, emptyBag, emptyBag, emptyLIE)
 
 tcPat tc_bndr (ParPatIn parend_pat) pat_ty
   = tcPat tc_bndr parend_pat pat_ty