[Bug c++/58252] [4.9 Regression] ice in gimple_get_virt_method_for_binfo with -O2

[trippels at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58252

--- Comment #9 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
Here's a small testcase that ICEs even with the patch from comment 7 applied:

markus@x4 library % < test.ii
typedef enum {} nsresult;
class B {
  void *mMappedMemory;

public:
  virtual int m_fn1();
};
class C : public virtual B {};
class D : C {
  virtual nsresult m_fn2();
};
nsresult D::m_fn2() {
  switch (0)
  case 0:
  m_fn1();
}
markus@x4 library % c++ -r -nostdlib -flto -O2 test.ii
lto1: internal compiler error: in record_target_from_binfo, at ipa-devirt.c:673