SwiftUI3.0 What the hell is this? Help!

What the hell is this? I code a view in Xcode 13 beta 5 and run it in iOS 15 beta 6. I don't understand what these error message mean, please help!

dyld4 config: DYLD_LIBRARY_PATH=/usr/lib/system/introspection DYLD_INSERT_LIBRARIES=/Developer/usr/lib/libBacktraceRecording.dylib:/Developer/usr/lib/libMainThreadChecker.dylib:/Developer/Library/PrivateFrameworks/DTDDISupport.framework/libViewDebuggerSupport.dylib
dyld4 config: DYLD_LIBRARY_PATH=/usr/lib/system/introspection DYLD_INSERT_LIBRARIES=/Developer/usr/lib/libBacktraceRecording.dylib:/Developer/usr/lib/libMainThreadChecker.dylib:/Developer/Library/PrivateFrameworks/DTDDISupport.framework/libViewDebuggerSupport.dylib
dyld4 config: DYLD_LIBRARY_PATH=/usr/lib/system/introspection DYLD_INSERT_LIBRARIES=/Developer/usr/lib/libBacktraceRecording.dylib:/Developer/usr/lib/libMainThreadChecker.dylib:/Developer/Library/PrivateFrameworks/DTDDISupport.framework/libViewDebuggerSupport.dylib
dyld4 config: DYLD_LIBRARY_PATH=/usr/lib/system/introspection DYLD_INSERT_LIBRARIES=/Developer/usr/lib/libBacktraceRecording.dylib:/Developer/usr/lib/libMainThreadChecker.dylib:/Developer/Library/PrivateFrameworks/DTDDISupport.framework/libViewDebuggerSupport.dylib
import SwiftUI

@available(iOS 15.0, *)
struct ExerciseEditView: View {
  @Environment(\.presentationMode) var presentationMode: Binding<PresentationMode>

  @State var headerTitle: String = "Count"
  @State var name: String = ""
  @State var count: Int = 0
  @State var min: Int = 0
  @State var sec: Int = 0
  @State var weight: Int = 0
   
  var body: some View {
    Form{
      Section("Name"){
        TextField("name", text: $name, prompt: Text("name"))
      }
       
       
      Section(self.headerTitle){
        Picker("pickTime", selection: $headerTitle){
          Text("Count")
            .tag("Count")
          Text("Time")
            .tag("Time")
        }
        .pickerStyle(.segmented)
         
        if self.headerTitle == "Time" {
          Picker("time", selection: $min){
            ForEach(0...60, id:\.self){value in
              Text("\(value)")
                .tag(value)
            }
          }
          .pickerStyle(.wheel)
          .frame(height: 60)
        }else {
          Picker("count", selection: $count){
            ForEach(0...100, id:\.self){value in
              Text("\(value)")
                .tag(value)
            }
          }
          .pickerStyle(.wheel)
          .frame(height: 60)
        }
      }
      Section("Weight"){
        Picker("weight", selection: $weight){
          ForEach(0...500, id:\.self){value in
            Text("\(value)")
              .tag(value)
          }
        }
        .pickerStyle(.wheel)
        .frame(height: 60)
      }
    }
    .navigationTitle("Exercise")
    .navigationBarTitleDisplayMode(.large)
    .navigationBarItems(trailing: HStack{
      Button(action:{
        presentationMode.wrappedValue.dismiss()
      }){
        Text("Done")
      }
    })
  }
}
SwiftUI3.0 What the hell is this? Help!
 
 
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