[Bug middle-end/51585] New: [4.7 Regression] verify_flow_info failed ICE with virtual inheritance

[reichelt at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51585

             Bug #: 51585
           Summary: [4.7 Regression] verify_flow_info failed ICE with
                    virtual inheritance
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: reich...@gcc.gnu.org


The following valid code snippet triggers an ICE on trunk:

==========================
struct A {};

struct B : virtual A
{
  virtual A& foo();
};

struct C : B
{
  virtual B& foo();
};

B& C::foo() {}
==========================

bug.cc: In member function 'B& C::_ZTch0_v0_n12_N1C3fooEv()':
bug.cc:10:14: error: fallthru to exit from bb 2
bug.cc:10:14: error: fallthru edge after a control statement in bb 2
bug.cc:10:14: error: wrong outgoing edge flags at end of bb 2
bug.cc:10:14: internal compiler error: verify_flow_info failed
Please submit a full bug report, [etc.]