llvm/test/C++Frontend/2006-10-30-ClassBitfield.cpp

// RUN: %llvmgxx %s -emit-llvm -S -o -
// PR954

struct _Refcount_Base   {
  unsigned long _M_ref_count;
  int _M_ref_count_lock;
  _Refcount_Base() : _M_ref_count(0) {}
};

struct _Rope_RopeRep : public _Refcount_Base 
{
public:
  int _M_tag:8; 
};

int foo(_Rope_RopeRep* r) { return r->_M_tag; }