Resources.LoadAsync cannot be used in iOS

I want to load resources async when my game is running. So I decide to use Resources.LoadAsync.

Actually, It works well in Editor Mode. But when I get to build iOS, one error comes out.

1. I tried to delete this sentence Resources.LoadAsync and it built well. Then I added this sentence and this error came out again.

2. I tried to build Android from my PC, and it's OK. I can also run it in Editor Mode. This error only occurs when building iOS.

3. I tried to upgrade my Unity from 4.5.4 to 4.5.5, but this error is still there.

I find nobody who met the same problem before, so I have to get there and ask you guys.

I would appreciate any help. Thanks for your time.

my code is like this:

 using UnityEngine;
 using System.Collections;
 
 public class ExampleClass : MonoBehaviour {
     void Start() {
         StartCoroutine(LoadTexture());
     }
     IEnumerator LoadTexture() {
         GameObject go = GameObject.CreatePrimitive(PrimitiveType.Cube);
         ResourceRequest request = Resources.LoadAsync<Texture2D>("glass");
         yield return request;
         go.renderer.material.mainTexture = request.asset;
     }
 }

and when I build iOS, this error comes out:

Cross compilation job Assembly-CSharp.dll failed. UnityEngine.UnityException: Failed AOT cross compiler: /Applications/Unity/Unity.app/Contents/PlaybackEngines/iOSSupport/Tools/OSX/mono-xcompiler --aot=full,asmonly,nodebug,static,outfile="Assembly-CSharp.dll.s" "Assembly-CSharp.dll" current dir : /Users/xxxx/Desktop/ParkourX/Parkour/Temp/StagingArea/Data/Managed Env: Apple_PubSub_Socket_Render = '/tmp/launch-CawMnu/Render' LOGNAME = 'xxxx' __CHECKFIX1436934 = '1' MONO_PATH = '/Users/xxxx/Desktop/ParkourX/Parkour/Temp/StagingArea/Data/Managed' TMPDIR = '/var/folders/bn/ts33w4bs0sz9gtnyqwxf99_c0000gn/T/' USER = 'xxxx' SSH_AUTH_SOCK = '/tmp/launch-iXaAd5/Listeners' GC_DONT_GC = 'yes please' SHELL = '/bin/bash' __CF_USER_TEXT_ENCODING = '0x1F5:0:0' GAC_PATH = '/Users/xxxx/Desktop/ParkourX/Parkour/Temp/StagingArea/Data/Managed' HOME = '/Users/xxxx' PATH = '/usr/bin:/bin:/usr/sbin:/sbin' result file exists: False. Timed out: False stdout: stderr:

at UnityEditor.MonoProcessUtility.RunMonoProcess (System.Diagnostics.Process process, System.String name, System.String resultingFile) [0x00000] in unknown>:0 at UnityEditor.MonoCrossCompile.CrossCompileAOT (BuildTarget target, System.String crossCompilerAbsolutePath, System.String assembliesAbsoluteDirectory, CrossCompileOptions crossCompileOptions, System.String input, System.String output, System.String additionalOptions) [0x00000] in :0 at UnityEditor.MonoCrossCompile+JobCompileAOT.ThreadPoolCallback (System.Object threadContext) [0x00000] in :0 UnityEditor.HostView:OnGUI() Click to expand...

Error building Player: UnityException: Cross compilation failed.

If I delete this two sentences, like this below, it works through building iOS:

 using UnityEngine;
 using System.Collections;
 
 public class ExampleClass : MonoBehaviour {
     void Start() {
         StartCoroutine(LoadTexture());
     }
     IEnumerator LoadTexture() {
         GameObject go = GameObject.CreatePrimitive(PrimitiveType.Cube);
         /*ResourceRequest request = Resources.LoadAsync<Texture2D>("glass");
         yield return request;*/
         yield return null;
         //go.renderer.material.mainTexture = request.asset;
     }
 }