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@Nexuapex Nexuapex/bit_cast.h
Created Apr 1, 2018

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Minimal-dependencies implementation of bit_cast.
#include <string.h>
#if defined(__has_attribute)
#if __has_attribute(always_inline)
#define ALWAYS_INLINE __attribute__((always_inline))
#endif
#endif
#if defined(_MSC_VER)
// To reduce debug build overhead:
// Enable intrinsic memcpy: /Oi
// Enable force-inlining: /Ob1
#define ALWAYS_INLINE __forceinline
#endif
template <typename Dest, typename Source>
ALWAYS_INLINE Dest bit_cast(const Source& source)
{
static_assert(sizeof(Dest) == sizeof(Source), "bit_cast to type of a different size");
static_assert(__has_trivial_copy(Dest), "bit_cast to a type which is not trivially copyable");
static_assert(__has_trivial_copy(Source), "bit_cast from a type which is not trivially copyable");
// Note: could avoid calling constructor/destructor for Dest type, which is
// what this proposed implementation (for C++20 standardization) does:
// https://github.com/jfbastien/bit_cast/blob/master/bit_cast.h
Dest dest;
memcpy(&dest, &source, sizeof(dest));
return dest;
}
// Example:
// https://godbolt.org/g/oqFZFH
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