Ben Gamari pushed to branch wip/T26110 at Glasgow Haskell Compiler / GHC Commits: bb3b2fa7 by Ben Gamari at 2025-06-12T13:38:55-04:00 compiler: Fix seq'ing of typecheck output for timing As noted in #26110, previously the `withTiming` call characterising typechecking would fail to force anything at all. This meant that laziness could easily compromise the accuracy of timings. We now try to force a reasonable subset of `TcGblEnv`. I do *not* force the entire structure as many of its constituents have no easy way to reduce them to normal form. Fixes #26110. - - - - - 2 changed files: - compiler/GHC/Tc/Module.hs - compiler/GHC/Tc/Types.hs Changes: ===================================== compiler/GHC/Tc/Module.hs ===================================== @@ -211,7 +211,7 @@ tcRnModule hsc_env mod_sum save_rn_syntax | RealSrcSpan real_loc _ <- loc = withTiming logger (text "Renamer/typechecker"<+>brackets (ppr this_mod)) - (const ()) $ + (maybe () seqTcGblEnv . snd) $ initTc hsc_env hsc_src save_rn_syntax this_mod real_loc $ withTcPlugins hsc_env $ withDefaultingPlugins hsc_env $ ===================================== compiler/GHC/Tc/Types.hs ===================================== @@ -30,7 +30,7 @@ module GHC.Tc.Types( -- The environment types Env(..), - TcGblEnv(..), TcLclEnv(..), modifyLclCtxt, TcLclCtxt(..), + TcGblEnv(..), seqTcGblEnv, TcLclEnv(..), modifyLclCtxt, TcLclCtxt(..), setLclEnvTcLevel, getLclEnvTcLevel, setLclEnvLoc, getLclEnvLoc, lclEnvInGeneratedCode, IfGblEnv(..), IfLclEnv(..), @@ -171,10 +171,11 @@ import GHC.Unit.Module.Deps import GHC.Unit.Module.ModDetails import GHC.Utils.Error -import GHC.Utils.Outputable import GHC.Utils.Fingerprint -import GHC.Utils.Panic import GHC.Utils.Logger +import GHC.Utils.Misc ( seqList ) +import GHC.Utils.Outputable +import GHC.Utils.Panic import GHC.Builtin.Names ( isUnboundName ) @@ -697,6 +698,19 @@ data TcGblEnv -- ^ See Note [Generating fresh names for FFI wrappers] } +-- | Force the final result bits of a 'TcGblEnv'. This is used +-- to +seqTcGblEnv :: TcGblEnv -> () +seqTcGblEnv env = + tcg_type_env env `seq` + tcg_ann_env env `seq` + maybe () (`seqList` ()) (tcg_rn_exports env) `seq` + seqList (tcg_import_decls env) `seq` + seqList (tcg_merged env) `seq` + maybe () (`seq` ()) (tcg_rn_decls env) `seq` + tcg_dus env `seq` + () + -- NB: topModIdentity, not topModSemantic! -- Definition sites of orphan identities will be identity modules, not semantic -- modules. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/bb3b2fa7af0cd02a96c2223755654577... -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/bb3b2fa7af0cd02a96c2223755654577... You're receiving this email because of your account on gitlab.haskell.org.