Unity5f4: Bug in CharacterController.

Hello
I have problem with CharacterController in Unity5f4.
Its look like CharacterController not always detect collisions.
Sometimes just randomly ignore some BoxColliders etc and then CharacterController
just falling through collider.
Everytime when run a game sometimes some colliders is ignored, sometimes is all ok.

I prepare little code to reproduce this problem:

using UnityEngine;
using System.Collections;

public class Test : MonoBehaviour
{
    public        GameObject            toCharacter;            // any prefab with CharacterController
    public        GameObject            toCreate;                // any prefab with BoxCollider
    public        int                    amount = 250;            // how many cubes to create. more == greater chance of collider fail

    private        bool                onlyOneTime;
    private        CharacterController    cc;

    int TestCollision()
    {
        // now we testing boxcolliders floor...
        // sometimes charactercontroller.Move() ignore some boxcolliders
        int c = 0;
        for(int x=0;x<amount;x++)
            for(int y=0;y<amount;y++)
            {
                cc.transform.position = new Vector3(x*2,5,y*2);
                CollisionFlags cf = cc.Move(Vector3.down * 100);
                if((cf & CollisionFlags.Below) != 0) c++; 
            }
      return c;
    }

    void Start ()
    {
        // create charactercontroller for testing
        GameObject gp = (GameObject)Instantiate(toCharacter);
        cc = gp.GetComponent<CharacterController>();

        // create boxcolliders as floor for charactercontroller
        for(int x=0;x<amount;x++)
            for(int y=0;y<amount;y++)
                Instantiate(toCreate,new Vector3(x*2,0,y*2),Quaternion.identity);
    }
   
    void Update ()
    {
        if(onlyOneTime == false)
        {
            int x = TestCollision();
            Debug.Log( x + " boxes collided, but should " + (amount*amount) + " collided." );
            onlyOneTime = true;
        }
    }
}

everytime when i run i have different results in Debug.Log:

Run nr.1: (some colliders fail)
62454 boxes collided, but should 62500 collided.
Run nr.2: (sometimes is ok)
62500 boxes collided, but should 62500 collided.
Run nr.3: (some colliders fail)
62488 boxes collided, but should 62500 collided.
Run nr.4: (some colliders fail)
62470 boxes collided, but should 62500 collided.
Run nr.5: (again is all ok)
62500 boxes collided, but should 62500 collided.
Run nr.6: (some colliders fail)
62458 boxes collided, but should 62500 collided.
Run nr.7: (again ok)
62500 boxes collided, but should 62500 collided.
Run nr.8: (fail)
62464 boxes collided, but should 62500 collided.
Run nr.9: (one collider fail)
62499 boxes collided, but should 62500 collided.
Run nr.10: (now is ok)
62500 boxes collided, but should 62500 collided.

also i prepare unitypackage with test.scene.

2019465–130653–boxcollider.unitypackage (12.1 KB)

i tried smaller number of colliders like 5K i didn’t see any collisions missed …
in my opinion… i don’t think there is a game need that sort of huge of check of 62k+ in one frame.

Hello. I am expiriencing same issue, but it occurs randomly when I hit Play button and my scene is using not more than 50 colliders, maybe less.
Bump, please!

This sounds like it may be related to the following post: