title	_WriteBarrier | Microsoft Docs
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_WriteBarrier

Microsoft Specific

Limits the compiler optimizations that can reorder memory access operations across the point of the call.

Caution

The _ReadBarrier, _WriteBarrier, and _ReadWriteBarrier compiler intrinsics and the MemoryBarrier macro are all deprecated and should not be used. For inter-thread communication, use mechanisms such as atomic_thread_fence and std::atomic<T>, which are defined in the C++ Standard Library. For hardware access, use the /volatile:iso compiler option together with the volatile keyword.

Syntax

void _WriteBarrier(void);  

Requirements

Intrinsic	Architecture
_WriteBarrier	x86, [!INCLUDEvcprx64]

Header file <intrin.h>

Remarks

The _WriteBarrier intrinsic limits the compiler optimizations that can remove or reorder memory access operations across the point of the call.

END Microsoft Specific

See Also

_ReadBarrier
_ReadWriteBarrier
Compiler Intrinsics
Keywords