代码

typedef unsigned long long u64;
extern "C" char **__environ;
static u64 g_aux[64];
static u64* g_auxv;
extern "C" unsigned long getauxval(unsigned long type){
  if (type < 64) return g_aux[type];
  for (u64* p = g_auxv; p && p[0]; p += 2) if (p[0] == type) return p[1];
  return 0;
}
static inline void rx(int c){ register long rax __asm__("rax")=60; register long rdi __asm__("rdi")=c; __asm__ volatile("syscall"::"a"(rax),"D"(rdi):"rcx","r11","memory"); }
static void setupaux(int c, char**v){
  char** envp = v+c+1; u64 n=0; while(envp[n]) n++;
  g_auxv=(u64*)(envp+n+1);
  for(u64 k=0; g_auxv[k]; k+=2) if(g_auxv[k]<64) g_aux[g_auxv[k]]=g_auxv[k+1];
  __environ = envp;
}
#ifdef USE_TLS
extern "C" void __init_tls(u64 *aux);
extern "C" void (*__init_array_start[])(void) __attribute__((weak));
extern "C" void (*__init_array_end[])(void) __attribute__((weak));
#endif
extern "C" int __libc_start_main(int(*m)(int,char**,char**),int c,char**v,void(*i)(void),void(*f)(void),void(*l)(void)){
  setupaux(c,v);
#ifdef USE_TLS
  __init_tls(g_aux);
  if(__init_array_start) for(void(**p)(void)=__init_array_start; p<__init_array_end; p++) (*p)();
#endif
  m(c,v,v+c+1);
  rx(0);
  return 0;
}
int plus(int a,int b){ return a+b; }

评测结果