newlib scanf 函数一直卡住

change this file
	libgloss/libnosys/_exit.c

#include <limits.h>
#include "config.h"
#include <_ansi.h>
#include <_syslist.h>
#include <sys/syscall.h>
#include <unistd.h>

void
_exit (int rc)
{
        syscall(SYS_exit, rc);
  /* Default stub just causes a divide by 0 exception.  */
//  int x = rc / INT_MAX;
 // x = 4 / x;
//      abort();
  /* Convince GCC that this function never returns.  */
  //for (;;)
   // ;
}