diff options
| -rw-r--r-- | compiler/codeGen/StgCmmPrim.hs | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/compiler/codeGen/StgCmmPrim.hs b/compiler/codeGen/StgCmmPrim.hs index 2169465fbb..34c2d06e90 100644 --- a/compiler/codeGen/StgCmmPrim.hs +++ b/compiler/codeGen/StgCmmPrim.hs @@ -1350,6 +1350,10 @@ doWritePtrArrayOp :: CmmExpr doWritePtrArrayOp addr idx val = do dflags <- getDynFlags let ty = cmmExprType dflags val + -- This write barrier is to ensure that the heap writes to the object + -- referred to by val have happened before we write val into the array. + -- See #12469 for details. + emitPrimCall [] MO_WriteBarrier [] mkBasicIndexedWrite (arrPtrsHdrSize dflags) Nothing addr ty idx val emit (setInfo addr (CmmLit (CmmLabel mkMAP_DIRTY_infoLabel))) -- the write barrier. We must write a byte into the mark table: |