Error: Generic Array Creation

I don't understand the error of Generic Array Creation.
First I tried the following:

  public PCB[] getAll() {
       PCB[] res = new PCB[list.size()];
           for (int i = 0; i < res.length; i++) {
               res[i] = list.get(i);
            }
       list.clear();
       return res;
}

Then I tried doing this:

PCB[] res = new PCB[100];

I must be missing something cause that seems right. I tried looking it up I really did. And nothing is clicking.

My question is: What can I do to fix this?

the error is :

.\Queue.java:26: generic array creation
PCB[] res = new PCB[200];
            ^
Note: U:\Senior Year\CS451- file      
uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
1 error

Tool completed with exit code 1