Concurrent work on Array

Using Swift
1

Is is possible to partition an array into non-overlapping parts in a way the compiler recognizes this fact and thus knows that there is no possibility of a data race?

func doTest() async
{
	let arrSize = 10_000_000_000
	var byteArray: [UInt8] =  Array(repeating: 0, count: arrSize)
	let bytesPertask =      10_000_000
	let nbrTasks = arrSize / bytesPertask
	
	#if true	//	Swift 6: does not compile
	await withTaskGroup 
	{	taskGroup in	
	
		for i in 0 ..< nbrTasks	 
		{
			taskGroup.addTask()
			{
				/*	Swift 6 Compile Error: 
					Passing closure as a 'sending' parameter risks causing data races between code   
					in the current task and concurrent execution of the closure
				**/
				let startIndex = i * bytesPertask
				let endIndex = min( startIndex + bytesPertask, arrSize)
				
				for j in startIndex ..< endIndex { byteArray[j] = 1 }
			}
		}
		
		await taskGroup.waitForAll()
	}
	#else		//	Swift 5 or 6: compiles with Warning 
	byteArray.withUnsafeMutableBufferPointer
	{	pointer in	
	
		guard let bytePointer = pointer.baseAddress else	{return}
		DispatchQueue.concurrentPerform( iterations: nbrTasks)
		{
			i in
			
			let startIndex = i * bytesPertask
			let endIndex = min( startIndex + bytesPertask, arrSize)
			
			/*	Compile Warning: 
				Capture of 'bytePointer' with non-sendable type 'UnsafeMutablePointer<UInt8>' in 
				a '@Sendable' closure
			**/
			for j in startIndex ..< endIndex { bytePointer[j] = 1 }
		}
	}
	#endif
}

How to get rid of the warning with concurrentPerform?
How to make TaskGroup compile in Swift Language Mode 6?

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