Tiva TM4C123G strange behaviour

Hello Guys. 

Debugging this code I encountered strange behaviour

CODE:

#include <stdint.h>
#include <stdbool.h>
#include "inc/hw_types.h"
#include "inc/hw_gpio.h"
#include "driverlib/pin_map.h"
#include "driverlib/sysctl.c"
#include "driverlib/sysctl.h"
#include "driverlib/gpio.c"
#include "driverlib/gpio.h"

#define LED_PERIPH SYSCTL_PERIPH_GPIOF
#define LED_BASE GPIO_PORTF_BASE
#define RED_LED GPIO_PIN_1

#define Button_PERIPH SYSCTL_PERIPH_GPIOF
#define ButtonBase GPIO_PORTF_BASE
#define Button GPIO_PIN_4
#define Button2 GPIO_PIN_0

int main(void)
{
 //Set the clock to 80Mhz
  SysCtlClockSet(SYSCTL_SYSDIV_2_5|SYSCTL_USE_PLL|SYSCTL_OSC_MAIN|SYSCTL_XTAL_16MHZ);
  HWREG(GPIO_PORTF_BASE+GPIO_O_LOCK) = GPIO_LOCK_KEY;
  HWREG(GPIO_PORTF_BASE+GPIO_O_CR) |= GPIO_PIN_0;

  SysCtlPeripheralEnable(LED_PERIPH);
  SysCtlDelay(9);

  GPIOPinTypeGPIOInput(ButtonBase, Button);
  GPIOPinTypeGPIOInput(ButtonBase, Button2);
  GPIOPadConfigSet(ButtonBase ,Button,GPIO_STRENGTH_2MA,GPIO_PIN_TYPE_STD_WPU);
  GPIOPadConfigSet(ButtonBase ,Button2,GPIO_STRENGTH_2MA,GPIO_PIN_TYPE_STD_WPU); //When I comment out this line the LED blinks faster

  GPIOPinTypeGPIOOutput(LED_BASE, RED_LED);

  uint32_t value=0;
  uint8_t state=0;
  while(1){
    value= GPIOPinRead(ButtonBase,Button);
    if( (value & GPIO_PIN_4)==0)
      state^=RED_LED;

    GPIOPinWrite(LED_BASE,RED_LED, state);
    SysCtlDelay(7000000);
  }
}

When I comment out this line:

  GPIOPadConfigSet(ButtonBase ,Button2,GPIO_STRENGTH_2MA,GPIO_PIN_TYPE_STD_WPU);

The LED is blinking faster then when the line is not commented.

Another think that bothers me - When I press the reset button of the Target Board the code crashes and never runs properly again. What might cause this? With the blinking led I don't have such a problem.

Thank you.