arr = (StgMutArrPtrs *)allocate(sizeofW(StgMutArrPtrs) + n);
TICK_ALLOC_PRIM(sizeofW(StgMutArrPtrs), n, 0);
SET_HDR(arr, &stg_MUT_ARR_PTRS_FROZEN_info, CCS_SYSTEM);
arr = (StgMutArrPtrs *)allocate(sizeofW(StgMutArrPtrs) + n);
TICK_ALLOC_PRIM(sizeofW(StgMutArrPtrs), n, 0);
SET_HDR(arr, &stg_MUT_ARR_PTRS_FROZEN_info, CCS_SYSTEM);