title: Getting warning Incompatible pointer types assigning to 'NSMutableData' from NSData
body: <p>I am getting warning::Incompatible pointer types assigning to 'NSMutableData' from 'NSData' in below code </p>
  
  <pre><code>-(void) connectionDidFinishLoading:(NSURLConnection *) connection
  {
      NSLog(@"DONE. Received Bytes: %d", [webData length]);
      NSString *theXML = [[[NSString alloc] initWithBytes: [webData mutableBytes] length [webData length] encoding:NSUTF8StringEncoding] autorelease];
  
      theXML = [theXML stringByReplacingOccurrencesOfString:@"&amp;lt;" withString:@"&lt;"];
      theXML = [theXML stringByReplacingOccurrencesOfString:@"&amp;gt;" withString:@"&gt;"];
      NSLog(@"%@",theXML);
  
      if( xmlParser )
      {
          xmlParser = nil;
          [xmlParser release];
      }
  
      NSMutableString *str = [[NSMutableString alloc]initWithString:theXML];
      webData = [str dataUsingEncoding:NSUTF16StringEncoding];//WARNING
  
      xmlParser = [[[NSXMLParser alloc] initWithData:webData] autorelease];
      [xmlParser setDelegate:self];
      [xmlParser setShouldResolveExternalEntities: YES];
      [xmlParser parse];
  
      [connection release];
  }
  </code></pre>