pointer to LPC_GPIO1->DIR not working!

I used the following 2 statements to replace LPC_GPIO1->DIR |= (1 << pinNumber);

unsigned int volatile * const lpc_gpio1_dir_ptr = (unsigned int *) LPC_GPIO1->DIR                                                            
*lpc_gpio1_dir_ptr|= (1 << pinNumber);

But it does not work.

// ****************************************************************************
// Program - Blinky
// Description - Blink LED
// Author - TL Fong
// Version - 0.40
// Date - 2013jul12hkt2040
// License - Free
// Hardware - Somy ARM Cortex M0 LPC1114/301 Learning Board 
// Software - Keil uVision 4.71.2.0 ARM CC
// Method - Incremental testing
// Hardware configuration notes
//   1. LED1 is connected to PIO1-8 
// ****************************************************************************

#include <stdio.h>
#include "LPC11xx.h"
#include "timer.h"

void setPortPinDirection(int portNumber, int pinNumber)
  {
  unsigned int volatile * const lpc_gpio1_dir_ptr = (unsigned int *) LPC_GPIO1-
                                                                     >DIR;
    switch( portNumber )
    {
    case 1:
      LPC_GPIO1->DIR |= (1 << pinNumber);    
      // *lpc_gpio1_dir_ptr|= (1 << pinNumber);
      break;
    case 2:
      LPC_GPIO2->DIR |= (1 << pinNumber);
      break;    
    default:
      break;
    }
}

// #define PORTBASE 0x40000000
// unsigned int volatile * const port = (unsigned int *) PORTBASE;
// The variable port is a constant pointer to a volatile unsigned integer, so we can access the memory-mapped register using:
// *port = value; /* write to port */
// value = *port; /* read from port */


void setPortPinValue(int portNumber, int pinNumber, int pinValue)
{
switch( portNumber )
{
case 1:
 if (pinValue == 1)
 LPC_GPIO1->DATA &= ~(1 << pinNumber);        
else
 LPC_GPIO1->DATA |= (1 << pinNumber);
break;
    case 2:
      ;
 break;    
default:
 break;
}
}

void blinkLed(int ledNumber, int onTime, int offTime, int blinkCount)
{
int count;

switch( ledNumber )
{
case 1:
setPortPinDirection(1, 8);
 
 for (count = 0; count < blinkCount; count--)
 {
 setPortPinValue(1, 8, 0);
        delayTenthSecond(onTime);    
   setPortPinValue(1, 8, 1);
        delayTenthSecond(offTime);
 }
      break;
    case 2:
      ;
 break;    
default:
 break;
}
}

int main()
  {
setPortPinDirection(1, 8);
blinkLed(1, 5, 10, 20); // Led 1, off 0.5 sec, on 1 sec, blink 20 times

  }

// ****************************************************************************
// End of Program
// ****************************************************************************