diff --git a/backends/GenerateC.hs b/backends/GenerateC.hs
index 881b3f3..92a09b0 100644
--- a/backends/GenerateC.hs
+++ b/backends/GenerateC.hs
@@ -1581,7 +1581,7 @@ realFormals (A.Formal am t n)
 genProcSpec :: Level -> A.Name -> A.SpecType -> Bool -> CGen ()
 genProcSpec lvl n (A.Proc _ (sm, rm) fs (Just p)) forwardDecl
     =  do cs <- getCompState
-          let (header, params) = if n `Set.member` csParProcs cs
+          let (header, params) = if n `Map.member` csParProcs cs
                                     || rm == A.Recursive
                                    then (genParHeader, genParParams)
                                    else (genNormalHeader, return ())
diff --git a/data/CompState.hs b/data/CompState.hs
index c54a3c7..945ae6d 100644
--- a/data/CompState.hs
+++ b/data/CompState.hs
@@ -71,6 +71,10 @@ data NameType =
 -- | An item that has been pulled up.
 type PulledItem = (Meta, Either A.Specification A.Process) -- Either Spec or ProcThen
 
+-- | Whether a wrapper is for a FORK or a PAR
+data ParOrFork = ParWrapper | ForkWrapper
+  deriving (Show, Eq, Typeable, Data)
+
 -- | An index to identify an item involved in the type unification.
 newtype UnifyIndex = UnifyIndex (Meta, Either Int A.Name)
   deriving (Typeable, Data)
@@ -154,7 +158,7 @@ data CompState = CompState {
     csFunctionReturns :: Map String [A.Type],
     csPulledItems :: [[PulledItem]],
     csAdditionalArgs :: Map String [A.Actual],
-    csParProcs :: Set A.Name,
+    csParProcs :: Map A.Name ParOrFork,
     csUnifyId :: Int,
     -- The string is the operator, the name is the munged function name
     csOperators :: [(String, A.Name, [A.Type])],
@@ -215,7 +219,7 @@ emptyState = CompState {
     csFunctionReturns = Map.empty,
     csPulledItems = [],
     csAdditionalArgs = Map.empty,
-    csParProcs = Set.empty,
+    csParProcs = Map.empty,
     csUnifyId = 0,
     csOperators = [],
     csWarnings = []
diff --git a/pregen/GenNavAST.hs b/pregen/GenNavAST.hs
index 435c1db..50d2ba6 100644
--- a/pregen/GenNavAST.hs
+++ b/pregen/GenNavAST.hs
@@ -42,6 +42,7 @@ main = do
       , genMapInstance (undefined :: String) (undefined :: [AST.Type])
       , genMapInstance (undefined :: String) (undefined :: [AST.Actual])
       , genMapInstance (undefined :: String) (undefined :: Set.Set CompState.NameAttr)
+      , genMapInstance (undefined :: AST.Name) (undefined :: CompState.ParOrFork)
       -- All the sets that are in CompState:
       , genSetInstance (undefined :: Errors.WarningType)
       , genSetInstance (undefined :: String)
diff --git a/transformations/SimplifyProcs.hs b/transformations/SimplifyProcs.hs
index db8b844..f1f2de4 100644
--- a/transformations/SimplifyProcs.hs
+++ b/transformations/SimplifyProcs.hs
@@ -21,6 +21,7 @@ module SimplifyProcs (simplifyProcs, fixLowReplicators) where
 
 import Control.Monad.State
 import Data.Generics (Data)
+import qualified Data.Map as Map
 import Data.Maybe
 import qualified Data.Set as Set
 
@@ -122,16 +123,16 @@ parsToProcs = pass "Wrap PAR subprocesses in PROCs"
         =  do s' <- doStructured s
               return $ A.Par m pm s'
     doProcess (A.Fork m n p)
-        =  wrapProcess (A.Fork m n) m p >>* A.Seq m
+        =  wrapProcess (A.Fork m n, ForkWrapper) m p >>* A.Seq m
     doProcess p = return p
 
     -- FIXME This should be generic and in Pass.
     doStructured :: A.Structured A.Process -> PassM (A.Structured A.Process)
-    doStructured = transformOnly (wrapProcess id)
+    doStructured = transformOnly (wrapProcess (id, ParWrapper))
 
-    wrapProcess wrap m p
+    wrapProcess (wrap, ty) m p
           =  do s@(A.Specification _ n _) <- makeNonceProc m p
-                modify (\cs -> cs { csParProcs = Set.insert n (csParProcs cs) })
+                modify (\cs -> cs { csParProcs = Map.insert n ty (csParProcs cs) })
                 return $ A.Spec m s (A.Only m (wrap $ A.ProcCall m n []))
 
 -- | Turn parallel assignment into multiple single assignments through temporaries.