[Bug 31335] New: __RTDynamicCast (aka dynamic_cast<>) broken on win64

http://bugs.winehq.org/show_bug.cgi?id=31335

Bug #: 31335
           Summary: __RTDynamicCast (aka dynamic_cast<>) broken on win64
           Product: Wine
           Version: 1.5.9
          Platform: x86
        OS/Version: Linux
            Status: NEW
          Severity: normal
          Priority: P2
         Component: msvcrt
        AssignedTo: [e-mail]
        ReportedBy: [e-mail]
    Classification: Unclassified

An MFC app compiled with Visual C++ 2010 for 64 bit failed with builtin
msvcr100.dll.  The +msvcrt log shows things like

trace:msvcrt:MSVCRT___RTDynamicCast obj: 0x14a008 unknown: 0 src: 0x403000
{vtable=0x4021e8 name=.?AVCObject@@ ()} dst: 0x403018 {vtable=0x4021e8
name=.?AVCPerson@@ ()} do_throw: 0)
trace:msvcrt:dump_obj_locator 0x402240: sig=00000000 base_offset=00000000
flags=00000000 type=0x403018 {vtable=0x4021e8 name=.?AVCPerson@@ ()}
hierarchy=0x402254
trace:msvcrt:dump_obj_locator   hierarchy: sig=00000000 attr=00000000 len=2
base classes=0x402264
trace:msvcrt:dump_obj_locator     base class 0x402270: num 1 off 0,-1,0 attr
00000040 type 0x403018 {vtable=0x4021e8 name=.?AVCPerson@@ ()}
trace:msvcrt:dump_obj_locator     base class 0x40228c: num 0 off 0,-1,0 attr
00000040 type 0x403000 {vtable=0x4021e8 name=.?AVCObject@@ ()}

(Can't tell what +relay shows because of bug 31330.)

The very first RTTI dynamic_cast I tried seems to reproduce the problem;
it throws the exception
Unhandled exception: C++ exception(object = 0x0022fbc0, type = 0x7fe293732980)
in 64-bit code (0x000000007b84a034).
when it should have succeed.

See attachment for kinda-rtti.cc, kinda-rtti-64.exe, and kinda-rtti.exe,
built with Visual C+ 2010's cl.exe /MD for 64 and 32 bits respectively
(as well as kinda-rtci.cc, kinda-rtci-64.exe, and kinda-rtci.exe, which
demonstrates that the older RTCI seems to work fine on 64 bits,
so older MFC apps might not run into this problem.)