Overlapping access warning in withUnsafeMutableBytes

Using Swift
6

You could also capture a copy of data or its count in the closure's capture list:

data.withUnsafeMutableBytes {[data] ptr in
  ptr[0] = UInt8(data.count)
}

data.withUnsafeMutableBytes {[count = data.count] ptr in
  ptr[0] = UInt8(count)
}

The capture list gets evaluated and the results captured by value when the closure is formed, before the exclusive access begins, avoiding the overlapping access.

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