diff options
Diffstat (limited to 'compiler/simplCore/CoreMonad.lhs')
| -rw-r--r-- | compiler/simplCore/CoreMonad.lhs | 17 |
1 files changed, 16 insertions, 1 deletions
diff --git a/compiler/simplCore/CoreMonad.lhs b/compiler/simplCore/CoreMonad.lhs index 3afb8cdf5d..31547e14a2 100644 --- a/compiler/simplCore/CoreMonad.lhs +++ b/compiler/simplCore/CoreMonad.lhs @@ -762,7 +762,8 @@ instance Monad CoreM where mx >>= f = CoreM $ \s -> do (x, s', w1) <- unCoreM mx s (y, s'', w2) <- unCoreM (f x) s' - return (y, s'', w1 `plusWriter` w2) + let w = w1 `plusWriter` w2 -- forcing w before returning avoids a space leak (Trac #7702) + return $ seq w (y, s'', w) instance Applicative CoreM where pure = return @@ -781,6 +782,12 @@ instance MonadUnique CoreM where modifyS (\s -> s { cs_uniq_supply = us2 }) return us1 + getUniqueM = do + us <- getS cs_uniq_supply + let (u,us') = takeUniqFromSupply us + modifyS (\s -> s { cs_uniq_supply = us' }) + return u + runCoreM :: HscEnv -> RuleBase -> UniqSupply @@ -896,6 +903,14 @@ not be a problem, except that the new copy has its own mutable state that is not shared with that state that has already been initialized by the original GHC package. +(NB This mechanism is sufficient for granting plugins read-only access to +globals that are guaranteed to be initialized before the plugin is loaded. If +any further synchronization is necessary, I would suggest using the more +sophisticated mechanism involving GHC.Conc.Sync.sharedCAF and rts/Globals.c to +share a single instance of the global variable among the compiler and the +plugins. Perhaps we should migrate all global variables to use that mechanism, +for robustness... -- NSF July 2013) + This leads to loaded plugins calling GHC code which pokes the static flags, and then dying with a panic because the static flags *it* sees are uninitialized. |