strange behavior when compile multi controllers project
<p>I have some codes as below</p>

<pre><code>#import &lt;UIKit/UIKit.h&gt;

@interface ViewMoreSettingController : UIViewController &lt;  UITableViewDelegate,     UITableViewDataSource &gt;
{}



@end




#import "ViewMoreSettingController.h"


@implementation ViewMoreSettingController

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
    // Custom initialization
}
return self;
}

- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view.
}

- (void)viewDidUnload
{
[super viewDidUnload];
// Release any retained subviews of the main view.
}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return (interfaceOrientation == UIInterfaceOrientationPortrait);
}

@end
</code></pre>

<p>// "MoreController.h"</p>

<pre><code>#import &lt;UIKit/UIKit.h&gt;
@class ViewMoreSettingController;


@interface MoreController : UIViewController  &lt;UITableViewDataSource,UITableViewDelegate&gt;{


ViewMoreSettingController *vViewMoreSettingController;
}


@property (retain,nonatomic) ViewMoreSettingController *vViewMoreSettingController;

@end
</code></pre>

<p>//------------------------------"MoreController.m"</p>

<pre><code>#import "MoreController.h"

#import "ViewMoreSettingController.h"


@implementation MoreController

@synthesize vViewMoreSettingController;

-(void)doSomething
{


        ViewMoreSettingController * temController ;
        temController=[[ViewMoreSettingController alloc]initWithNibName:@"ViewMoreSetting" bundle:nil];//a: if remove this line it will compile successfully

        [self.navigationController  pushViewController:vViewMoreSettingController animated:YES];


        [temController release];






   }
</code></pre>

<p>it will report </p>

<p>Undefined symbols for architecture i386:
  "_OBJC_CLASS_$_ViewMoreSettingController", referenced from:
      objc-class-ref in MoreController.o
ld: symbol(s) not found for architecture i386
clang: error: linker command failed with exit code 1 (use -v to see invocation)</p>

<p>if I remove line a: it will compile successfully.</p>

<p>Welcome any comment</p>
