merge up to ghc HEAD 16-Apr-2011

[ghc-hetmet.git] / compiler / rename / RnBinds.lhs

diff --git a/compiler/rename/RnBinds.lhs b/compiler/rename/RnBinds.lhs
index 4899adb..6c57cb2 100644 (file)
--- a/compiler/rename/RnBinds.lhs
+++ b/compiler/rename/RnBinds.lhs
@@ -357,7 +357,9 @@ rnLocalValBindsAndThen binds@(ValBindsIn _ sigs) thing_inside
                --      let x = x in 3
                -- should report 'x' unused
        ; let real_uses = findUses dus result_fvs
-       ; warnUnusedLocalBinds bound_names real_uses
+             -- Insert fake uses for variables introduced implicitly by wildcards (#4404)
+             implicit_uses = hsValBindsImplicits binds'
+       ; warnUnusedLocalBinds bound_names (real_uses `unionNameSets` implicit_uses)
 
        ; let
             -- The variables "used" in the val binds are: 
@@ -773,7 +775,7 @@ rnGRHS ctxt = wrapLocFstM (rnGRHS' ctxt)
 rnGRHS' :: HsMatchContext Name -> GRHS RdrName -> RnM (GRHS Name, FreeVars)
 rnGRHS' ctxt (GRHS guards rhs)
   = do { pattern_guards_allowed <- xoptM Opt_PatternGuards
-       ; ((guards', rhs'), fvs) <- rnStmts (PatGuard ctxt) guards $
+        ; ((guards', rhs'), fvs) <- rnStmts (PatGuard ctxt) guards $ \ _ ->
                                    rnLExpr rhs
 
        ; unless (pattern_guards_allowed || is_standard_guard guards')