Add {-# OPTIONS_GHC -w #-} and some blurb to all compiler modules

[ghc-hetmet.git] / compiler / coreSyn / CoreSubst.lhs

diff --git a/compiler/coreSyn/CoreSubst.lhs b/compiler/coreSyn/CoreSubst.lhs
index 6a2255c..2029180 100644 (file)
--- a/compiler/coreSyn/CoreSubst.lhs
+++ b/compiler/coreSyn/CoreSubst.lhs
@@ -6,6 +6,13 @@
 Utility functions on @Core@ syntax
 
 \begin{code}
+{-# OPTIONS_GHC -w #-}
+-- The above warning supression flag is a temporary kludge.
+-- While working on this module you are encouraged to remove it and fix
+-- any warnings in the module. See
+--     http://hackage.haskell.org/trac/ghc/wiki/WorkingConventions#Warnings
+-- for details
+
 module CoreSubst (
        -- Substitution stuff
        Subst, TvSubstEnv, IdSubstEnv, InScopeSet,
@@ -45,6 +52,8 @@ import Outputable
 import PprCore         ()              -- Instances
 import Util
 import FastTypes
+
+import Data.List
 \end{code}
 
 
@@ -307,6 +316,7 @@ substRecBndrs subst bndrs
 substIdBndr :: Subst           -- Substitution to use for the IdInfo
            -> Subst -> Id      -- Substitition and Id to transform
            -> (Subst, Id)      -- Transformed pair
+                               -- NB: unfolding may be zapped
 
 substIdBndr rec_subst subst@(Subst in_scope env tvs) old_id
   = (Subst (in_scope `extendInScopeSet` new_id) new_env tvs, new_id)
@@ -324,6 +334,7 @@ substIdBndr rec_subst subst@(Subst in_scope env tvs) old_id
        -- rec_subst, when dealing with a mutually-recursive group
     new_id = maybeModifyIdInfo mb_new_info id2
     mb_new_info = substIdInfo rec_subst (idInfo id2)
+       -- NB: unfolding info may be zapped
 
        -- Extend the substitution if the unique has changed
        -- See the notes with substTyVarBndr for the delVarEnv