diff options
| -rw-r--r-- | ghc/compiler/coreSyn/CoreTidy.lhs | 30 |
1 files changed, 24 insertions, 6 deletions
diff --git a/ghc/compiler/coreSyn/CoreTidy.lhs b/ghc/compiler/coreSyn/CoreTidy.lhs index 64d7c738d6..dc2c600fbc 100644 --- a/ghc/compiler/coreSyn/CoreTidy.lhs +++ b/ghc/compiler/coreSyn/CoreTidy.lhs @@ -20,8 +20,8 @@ import VarEnv import VarSet import Var ( Id, Var ) import Id ( idType, idInfo, idName, isExportedId, - idSpecialisation, idUnique, - mkVanillaGlobal, isLocalId, isImplicitId, + idSpecialisation, idUnique, isDataConWrapId, + mkVanillaGlobal, isLocalId, hasNoBinding, mkUserLocal ) import IdInfo {- loads of stuff -} @@ -204,8 +204,8 @@ mkFinalTypeEnv type_env final_ids -- in interface files, because they are needed by importing modules when -- using the compilation manager - -- We keep constructor workers, because they won't appear - -- in the bindings from which final_ids are derived! + -- We keep "hasNoBinding" Ids, notably constructor workers, + -- because they won't appear in the bindings from which final_ids are derived! keep_it (AnId id) = hasNoBinding id -- Remove all Ids except constructor workers keep_it other = True -- Keep all TyCons and Classes \end{code} @@ -393,8 +393,26 @@ tidyTopBinder :: Module -> IdEnv Bool tidyTopBinder mod ext_ids cg_info_env tidy_env rhs env@(orig_env2, occ_env2, subst_env2) id - | isImplicitId id -- Don't mess with constructors, - = (env, id) -- record selectors, and the like + | isDataConWrapId id -- Don't tidy constructor wrappers + = (env, id) -- The Id is stored in the TyCon, so it would be bad + -- if anything changed + +-- HACK ALERT: we *do* tidy record selectors. Reason: they mention error +-- messages, which may be floated out: +-- x_field pt = case pt of +-- Rect x y -> y +-- Pol _ _ -> error "buggle wuggle" +-- The error message will be floated out so we'll get +-- lvl5 = error "buggle wuggle" +-- x_field pt = case pt of +-- Rect x y -> y +-- Pol _ _ -> lvl5 +-- +-- When this happens, it's vital that the Id exposed to importing modules +-- (by ghci) mentions lvl5 in its unfolding, not the un-tidied version. +-- +-- What about the Id in the TyCon? It probably shouldn't be in the TyCon at +-- all, but in any case it will have the error message inline so it won't matter. | otherwise -- This function is the heart of Step 2 |