diff options
| -rw-r--r-- | compiler/main/TidyPgm.lhs | 10 |
1 files changed, 3 insertions, 7 deletions
diff --git a/compiler/main/TidyPgm.lhs b/compiler/main/TidyPgm.lhs index be4c683276..174054ee61 100644 --- a/compiler/main/TidyPgm.lhs +++ b/compiler/main/TidyPgm.lhs @@ -58,7 +58,7 @@ import qualified ErrUtils as Err import Control.Monad import Data.Function import Data.List ( sortBy ) -import Data.IORef ( readIORef, writeIORef ) +import Data.IORef ( atomicModifyIORef ) \end{code} @@ -857,9 +857,7 @@ tidyTopName mod nc_var maybe_ref occ_env id -- Now we get to the real reason that all this is in the IO Monad: -- we have to update the name cache in a nice atomic fashion - | local && internal = do { nc <- readIORef nc_var - ; let (nc', new_local_name) = mk_new_local nc - ; writeIORef nc_var nc' + | local && internal = do { new_local_name <- atomicModifyIORef nc_var mk_new_local ; return (occ_env', new_local_name) } -- Even local, internal names must get a unique occurrence, because -- if we do -split-objs we externalise the name later, in the code generator @@ -867,9 +865,7 @@ tidyTopName mod nc_var maybe_ref occ_env id -- Similarly, we must make sure it has a system-wide Unique, because -- the byte-code generator builds a system-wide Name->BCO symbol table - | local && external = do { nc <- readIORef nc_var - ; let (nc', new_external_name) = mk_new_external nc - ; writeIORef nc_var nc' + | local && external = do { new_external_name <- atomicModifyIORef nc_var mk_new_external ; return (occ_env', new_external_name) } | otherwise = panic "tidyTopName" |