diff options
| -rw-r--r-- | System/Posix/Signals.hs | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/System/Posix/Signals.hs b/System/Posix/Signals.hs index 92b54b0..89dd12b 100644 --- a/System/Posix/Signals.hs +++ b/System/Posix/Signals.hs @@ -97,10 +97,11 @@ import Foreign.C import System.IO.Unsafe import System.Posix.Types import System.Posix.Internals +import Control.Concurrent (withMVar) #ifdef __GLASGOW_HASKELL__ #include "Signals.h" -import GHC.Conc ( ensureIOManagerIsRunning ) +import GHC.Conc ( ensureIOManagerIsRunning, signalHandlerLock ) #endif -- ----------------------------------------------------------------------------- @@ -322,6 +323,8 @@ installHandler int handler maybe_mask = do Just (SignalSet x) -> withForeignPtr x $ install' where install' mask = + -- prevent race with the IO manager thread, see #1922 + withMVar signalHandlerLock $ \_ -> alloca $ \p_sp -> do rc <- case handler of |