diff options
Diffstat (limited to 'compiler/GHC/Tc/Solver/Monad.hs')
| -rw-r--r-- | compiler/GHC/Tc/Solver/Monad.hs | 32 |
1 files changed, 19 insertions, 13 deletions
diff --git a/compiler/GHC/Tc/Solver/Monad.hs b/compiler/GHC/Tc/Solver/Monad.hs index b5cf81ad9d..b9a9354eff 100644 --- a/compiler/GHC/Tc/Solver/Monad.hs +++ b/compiler/GHC/Tc/Solver/Monad.hs @@ -25,7 +25,7 @@ module GHC.Tc.Solver.Monad ( updWorkListTcS, pushLevelNoWorkList, - runTcPluginTcS, addUsedGRE, addUsedGREs, keepAlive, + runTcPluginTcS, recordUsedGREs, matchGlobalInst, TcM.ClsInstResult(..), QCInst(..), @@ -151,7 +151,7 @@ import GHC.Core.TyCon import GHC.Types.Error ( mkPlainError, noHints ) import GHC.Types.Name import GHC.Types.TyThing -import GHC.Types.Name.Reader ( GlobalRdrEnv, GlobalRdrElt ) +import GHC.Types.Name.Reader import GHC.Unit.Module ( HasModule, getModule, extractModule ) import qualified GHC.Rename.Env as TcM @@ -175,7 +175,8 @@ import Control.Monad import GHC.Utils.Monad import Data.IORef import GHC.Exts (oneShot) -import Data.List ( mapAccumL, partition, find ) +import Data.List ( mapAccumL, partition ) +import Data.Foldable #if defined(DEBUG) import GHC.Data.Graph.Directed @@ -1373,17 +1374,22 @@ tcLookupClass c = wrapTcS $ TcM.tcLookupClass c tcLookupId :: Name -> TcS Id tcLookupId n = wrapTcS $ TcM.tcLookupId n --- Setting names as used (used in the deriving of Coercible evidence) --- Too hackish to expose it to TcS? In that case somehow extract the used --- constructors from the result of solveInteract -addUsedGREs :: [GlobalRdrElt] -> TcS () -addUsedGREs gres = wrapTcS $ TcM.addUsedGREs gres +-- Any use of this function is a bit suspect, because it violates the +-- pure veneer of TcS. But it's just about warnings around unused imports +-- and local constructors (GHC will issue fewer warnings than it otherwise +-- might), so it's not worth losing sleep over. +recordUsedGREs :: Bag GlobalRdrElt -> TcS () +recordUsedGREs gres + = do { wrapTcS $ TcM.addUsedGREs gre_list + -- If a newtype constructor was imported, don't warn about not + -- importing it... + ; wrapTcS $ traverse_ (TcM.keepAlive . greMangledName) gre_list } + -- ...and similarly, if a newtype constructor was defined in the same + -- module, don't warn about it being unused. + -- See Note [Tracking unused binding and imports] in GHC.Tc.Utils. -addUsedGRE :: Bool -> GlobalRdrElt -> TcS () -addUsedGRE warn_if_deprec gre = wrapTcS $ TcM.addUsedGRE warn_if_deprec gre - -keepAlive :: Name -> TcS () -keepAlive = wrapTcS . TcM.keepAlive + where + gre_list = bagToList gres -- Various smaller utilities [TODO, maybe will be absorbed in the instance matcher] -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |