4 files changed, 11 insertions, 0 deletions
diff --git a/compiler/codeGen/CgPrimOp.hs b/compiler/codeGen/CgPrimOp.hs
index 6fe934b54c..72bbf6cc58 100644
--- a/compiler/codeGen/CgPrimOp.hs
+++ b/compiler/codeGen/CgPrimOp.hs
@@ -155,6 +155,8 @@ emitPrimOp [res] SparkOp [arg] live = do
   where
 	newspark = CmmLit (CmmLabel (mkCmmCodeLabel rtsPackageId (fsLit "newSpark")))
 
+emitPrimOp [res] GetCCCSOp [] _live
+   = stmtC (CmmAssign (CmmLocal res) curCCS)
 
 emitPrimOp [res] ReadMutVarOp [mutv] _
    = stmtC (CmmAssign (CmmLocal res) (cmmLoadIndexW mutv fixedHdrSize gcWord))
diff --git a/compiler/codeGen/StgCmmPrim.hs b/compiler/codeGen/StgCmmPrim.hs
index f8cc4256f4..d546c38a90 100644
--- a/compiler/codeGen/StgCmmPrim.hs
+++ b/compiler/codeGen/StgCmmPrim.hs
@@ -228,6 +228,9 @@ emitPrimOp [res] SparkOp [arg]
             [(CmmReg (CmmGlobal BaseReg), AddrHint), ((CmmReg (CmmLocal tmp)), AddrHint)]
         emit (mkAssign (CmmLocal res) (CmmReg (CmmLocal tmp)))
 
+emitPrimOp [res] GetCCCSOp []
+   = emit (mkAssign (CmmLocal res) curCCS)
+
 emitPrimOp [res] ReadMutVarOp [mutv]
    = emit (mkAssign (CmmLocal res) (cmmLoadIndexW mutv fixedHdrSize gcWord))
 
diff --git a/compiler/prelude/primops.txt.pp b/compiler/prelude/primops.txt.pp
index 204dce2e59..ceb9226594 100644
--- a/compiler/prelude/primops.txt.pp
+++ b/compiler/prelude/primops.txt.pp
@@ -1799,6 +1799,9 @@ primop  TraceCcsOp "traceCcs#" GenPrimOp
    has_side_effects = True
    out_of_line = True
 
+primop  GetCCCSOp "getCCCS#" GenPrimOp
+   State# s -> (# State# s, Addr# #)
+
 ------------------------------------------------------------------------
 section "Etc" 
 	{Miscellaneous built-ins}
diff --git a/rts/Capability.c b/rts/Capability.c
index fd9f64f147..6c84d1ec35 100644
--- a/rts/Capability.c
+++ b/rts/Capability.c
@@ -267,6 +267,8 @@ initCapability( Capability *cap, nat i )
 
 #ifdef PROFILING
     cap->r.rCCCS = CCS_SYSTEM;
+#else
+    cap->r.rCCCS = NULL;
 #endif
 
     traceCapsetAssignCap(CAPSET_OSPROCESS_DEFAULT, i);
@@ -614,6 +616,7 @@ waitForReturnCapability (Capability **pCap, Task *task)
 #ifdef PROFILING
     cap->r.rCCCS = CCS_SYSTEM;
 #endif
+
     ASSERT_FULL_CAPABILITY_INVARIANTS(cap,task);
 
     debugTrace(DEBUG_sched, "resuming capability %d", cap->no);