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AndrewTsao/container_of.h

Created May 17, 2015 14:35
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CONTAINER_OF for C++
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container_of.h
template <class T, typename M>
T* container_of(M *m, const M T::*mp) {
static const T * null = reinterpret_cast<const T *>(null);
static const ptrdiff_t offset = reinterpret_cast<const ptrdiff_t>(&(null->*mp));
return reinterpret_cast<T*>(reinterpret_cast<char*>(m) - offset);
}
@hutorny
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hutorny commented Nov 14, 2016

I'm not sure if this is right: static const T * null = reinterpret_cast<const T *>(null);
Maybe you meant static const T * null = reinterpret_cast<const T *>(nullptr); ?
In such case I think you would have to use static_cast.

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