Why accelX always equal to zero?

In my app when I make archive (Product -> Archive) the share to get the .api then go to iTunes and install in my iPhone I have notice in the device console that accelX always equal to zero why?

Note if I click play in the Xcode all works properly.

This is my code :

- (void)accelerometer:(UIAccelerometer *)accelerometer 
    didAccelerate:(UIAcceleration *)acceleration {

CGSize winSize = [CCDirector sharedDirector].winSize;
   static float accelX = 0;
    #define kFilteringFactor 0.1
    #define kRestAccelX 0.6
    #define kShipMaxPointsPerSec (winSize.height*0.5)
    #define kMaxDiffX 0.2
    UIAccelerationValue rollingX;

rollingX = (acceleration.x * kFilteringFactor) + 
    (rollingX * (1.0 - kFilteringFactor));    

 accelX = acceleration.x - rollingX;
NSLog(@"accelX :%f",accelX);


float accelDiffX = kRestAccelX - ABS(accelX);
float accelFractionX = accelDiffX / kMaxDiffX;
float pointsPerSecX = kShipMaxPointsPerSec * accelFractionX;

_shipPointsPerSecY = pointsPerSecX;

}

the solution is to replace:

UIAccelerationValue rollingX;

by

UIAccelerationValue rollingX = 0;