if (!__malloc_initialized && !mcheck_used)
if (__malloc_initialized <= 0 && !mcheck_used)
mcheck (func)     void (*func) __P ((enum mcheck_status));{  abortfunc = (func != NULL) ? func : &mabort;  /* These hooks may not be safely inserted if malloc is already in use.  */  if (!__malloc_initialized && !mcheck_used)    {      old_free_hook = __free_hook;      __free_hook = freehook;      old_malloc_hook = __malloc_hook;      __malloc_hook = mallochook;      old_realloc_hook = __realloc_hook;      __realloc_hook = reallochook;      mcheck_used = 1;    }  return mcheck_used ? 0 : -1;}