Avoid undefined behavior in Windows ftok(3) emulation #9958
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`.nFileIndexHigh` is a unsigned 32bit number. Casting that to `__int64` and shifting left by 32bits triggers undefined behavior if the most significant bit of `.nFileIndexHigh` is set. We could avoid that by casting to `(__uint64)`, but in that case the whole clause doesn't have an effect anymore, so we drop it altogether.
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.nFileIndexHighis a unsigned 32bit number. Casting that to__int64and shifting left by 32bits triggers undefined behavior if the most significant bit of.nFileIndexHighis set. We could avoid that by casting to(__uint64), but in that case the whole clause doesn't have an effect anymore, so we drop it altogether.