modernc.org/cc@v1.0.1/testdata/gcc-6.3.0/gcc/testsuite/gcc.c-torture/compile/20081119-1.c (about)

     1  unsigned long long
     2  f (__builtin_va_list  ap)
     3  {
     4    return __builtin_va_arg (ap, unsigned long long);
     5  }