Swift 结构警告 "Initialization of 'UnsafeMutableRawPointer' results in a dangling pointer"

Question

我搜索了很多类似问题的答案，但找不到解决此问题的正确答案。我有一个非常简单的结构

  struct MyParameters {
    var position: CGPoint
    var size: Float
  }

然后这个初始化

 var parameters = MyParameters(position: .zero, size: 0)
 let pointer = UnsafeMutableRawPointer(&parameters)

我在第二行收到警告

 Initialization of 'UnsafeMutableRawPointer' results in a dangling pointer

我知道编译器在抱怨，因为它不确定指针指向的内存是否会继续存在。但是在那种情况下传递指针的正确方法是什么？

Answer 1

使用withUnsafeMutableBytes

func foo() {
    var parameters = MyParameters(position: .zero, size: 0)
    
    withUnsafeMutableBytes(of: &parameters) { pointer in
         // here the lifetime is known
    }
}

Swift 结构警告 "Initialization of 'UnsafeMutableRawPointer' results in a dangling pointer"

Swift Struct Warning "Initialization of 'UnsafeMutableRawPointer' results in a dangling pointer"

ios

swift

struct

swift4