Ded Ded - 3 months ago 37
C++ Question

C++ RTTI in a Windows 64-bit VectoredExceptionHandler, MS Visual Studio 2015

I'm working on small Windows Exception handling engine trying to gather maximum information from the system, including C++ exceptions RTTI.

In a 32-bit VectoredExceptionHandler compiled by MSVS 2015, I successfully can obtain std::type_info pointer to RTTI of the type being thrown. It can easily be found in

((_ThrowInfo*) ExceptionPointers->ExceptionRecord->ExceptionInformation[2])->pCatchableTypeArray->arrayOfCatchableTypes[0]
(see classic article of Raymond Chen, some definitions from MS's
ehdata.h
file and many others). This method is based on fetching
pCatchableTypeArray
member of MSVC built-in
_ThrowInfo
structure data which is built by the compiler.

But in 64-bit environment,
_ThrowInfo
contains no direct RTTI: unfortunately,
pCatchableTypeArray
is NULL. In disassembly window, I see that it is NULL even before a call to
_CxxThrowException
, main MS throw-handler. I searched through a number of articles concerning new 64-bit exception-handling mechanism used in MSVC, but there is no information on RTTI. But maybe I missed something.

Are there any ways to obtain std::type_info (or simply type name) of the C++ exception being thrown in a vectored exception handler working in 64-bit MSVC environment?

Here's the output of dumping 32-bit and 64-bit exception info:

32-bit (RTTI success):

VectoredExceptionHandler(): Start

exc->ExceptionCode = 0xE06D7363
exc->ExceptionAddress = 0x74E2C54F
exc->NumberParameters = 3
exc->ExceptionInformation[0] = 0x19930520 (sig)
exc->ExceptionInformation[1] = 0x004FFD9C (object)
exc->ExceptionInformation[2] = 0x003AD85C (throwInfo)
exc->ExceptionInformation[3] = 0x005B18F8 (module)

throwInfo->attributes = 0x00000000
throwInfo->pmfnUnwind = 0x00000000
throwInfo->pForwardCompat = 0x00000000
throwInfo->pCatchableTypeArray = 0x003AD870

object = 0x004FFD9C
throwInfo = 0x003AD85C
module = 0x00000000

throwInfo->pCatchableTypeArray = 0x003AD870
cArray = 0x003AD870

cArray->arrayOfCatchableTypes[0] = 0x003AD878
cType = 0x003AD878

cType->pType = 0x003AFA70
type = 0x003AFA70

type->name() = "struct `int __cdecl main(void)'::`2'::meow_exception"
cType->sizeOrOffset = 4

VectoredExceptionHandler(): End

main(): catch (meow_exception { 3 })


64-bit (RTTI failure)

VectoredExceptionHandler(): Start

exc->ExceptionCode = 0xE06D7363
exc->ExceptionAddress = 0x000007FEFCE0A06D
exc->NumberParameters = 4
exc->ExceptionInformation[0] = 0x0000000019930520 (sig)
exc->ExceptionInformation[1] = 0x000000000025FBE0 (object)
exc->ExceptionInformation[2] = 0x000000013FC52AB0 (throwInfo)
exc->ExceptionInformation[3] = 0x000000013FBE0000 (module)

module = 0x000000013FBE0000

throwInfo->attributes = 0x00000000
throwInfo->pmfnUnwind = 0x0000000000000000
throwInfo->pForwardCompat = 0x0000000000072AD0
throwInfo->pCatchableTypeArray = 0x0000000000000000

VectoredExceptionHandler(): End

main(): catch (meow_exception { 3 })


The code used to get these dumps:

#include <stdio.h>
#include <typeinfo>
#include <windows.h>

//--------------------------------------------------------------------------------------------------

const unsigned EXCEPTION_CPP_MICROSOFT = 0xE06D7363, // '?msc'
EXCEPTION_CPP_MICROSOFT_EH_MAGIC_NUMBER1 = 0x19930520, // '?msc' version magic, see ehdata.h

EXCEPTION_OUTPUT_DEBUG_STRING = 0x40010006, // OutputDebugString() call
EXCEPTION_THREAD_NAME = 0x406D1388; // Passing name of thread to the debugger

void OutputDebugPrintf (const char* format, ...);

//--------------------------------------------------------------------------------------------------

long WINAPI VectoredExceptionHandler (EXCEPTION_POINTERS* pointers)
{
const EXCEPTION_RECORD* exc = pointers->ExceptionRecord;

if (exc->ExceptionCode == EXCEPTION_OUTPUT_DEBUG_STRING ||
exc->ExceptionCode == EXCEPTION_THREAD_NAME)
return EXCEPTION_CONTINUE_SEARCH;

OutputDebugPrintf ("\n%s(): Start\n\n", __func__);

OutputDebugPrintf ("exc->ExceptionCode = 0x%X\n", exc->ExceptionCode);
OutputDebugPrintf ("exc->ExceptionAddress = 0x%p\n", exc->ExceptionAddress);

if (exc->ExceptionInformation[0] == EXCEPTION_CPP_MICROSOFT_EH_MAGIC_NUMBER1 &&
exc->NumberParameters >= 3)
{
OutputDebugPrintf ("exc->NumberParameters = %u\n", exc->NumberParameters);

OutputDebugPrintf ("exc->ExceptionInformation[0] = 0x%p (sig)\n", (void*) exc->ExceptionInformation[0]);
OutputDebugPrintf ("exc->ExceptionInformation[1] = 0x%p (object)\n", (void*) exc->ExceptionInformation[1]);
OutputDebugPrintf ("exc->ExceptionInformation[2] = 0x%p (throwInfo)\n", (void*) exc->ExceptionInformation[2]);
OutputDebugPrintf ("exc->ExceptionInformation[3] = 0x%p (module)\n", (void*) exc->ExceptionInformation[3]);
OutputDebugPrintf ("\n");

HMODULE module = (exc->NumberParameters >= 4)? (HMODULE) exc->ExceptionInformation[3] : NULL;

if (module)
{
OutputDebugPrintf ("module = 0x%p\n", module);
OutputDebugPrintf ("\n");
}

const _ThrowInfo* throwInfo = (const _ThrowInfo*) exc->ExceptionInformation[2];

if (throwInfo)
{
OutputDebugPrintf ("throwInfo->attributes = 0x%08X\n", throwInfo->attributes);
OutputDebugPrintf ("throwInfo->pmfnUnwind = 0x%p\n", throwInfo->pmfnUnwind);
OutputDebugPrintf ("throwInfo->pForwardCompat = 0x%p\n", throwInfo->pForwardCompat);
OutputDebugPrintf ("throwInfo->pCatchableTypeArray = 0x%p\n", throwInfo->pCatchableTypeArray);
OutputDebugPrintf ("\n");
}

if (throwInfo && throwInfo->pCatchableTypeArray)
{
#define RVA_TO_VA_(type, addr) ( (type) ((uintptr_t) module + (uintptr_t) (addr)) )

OutputDebugPrintf ("object = 0x%p\n", (void*) exc->ExceptionInformation[1]);
OutputDebugPrintf ("throwInfo = 0x%p\n", (void*) throwInfo);
OutputDebugPrintf ("module = 0x%p\n", (void*) module);
OutputDebugPrintf ("\n");

const _CatchableTypeArray* cArray = RVA_TO_VA_(const _CatchableTypeArray*, throwInfo->pCatchableTypeArray);

OutputDebugPrintf ("throwInfo->pCatchableTypeArray = 0x%p\n", (void*) throwInfo->pCatchableTypeArray);
OutputDebugPrintf ("cArray = 0x%p\n\n", (void*) cArray);

const _CatchableType* cType = RVA_TO_VA_(const _CatchableType*, cArray->arrayOfCatchableTypes[0]);

OutputDebugPrintf ("cArray->arrayOfCatchableTypes[0] = 0x%p\n", (void*) cArray->arrayOfCatchableTypes[0]);
OutputDebugPrintf ("cType = 0x%p\n\n", (void*) cType);

const std::type_info* type = RVA_TO_VA_(const std::type_info*, cType->pType);

OutputDebugPrintf ("cType->pType = 0x%p\n", (void*) cType->pType);
OutputDebugPrintf ("type = 0x%p\n\n", (void*) type);

OutputDebugPrintf ("type->name() = \"%s\"\n", type->name());
OutputDebugPrintf ("cType->sizeOrOffset = %zu\n\n", (size_t) cType->sizeOrOffset);

#undef RVA_TO_VA_
}
}

OutputDebugPrintf ("%s(): End\n", __func__);
return EXCEPTION_CONTINUE_SEARCH;
}

//--------------------------------------------------------------------------------------------------

void OutputDebugPrintf (const char* format, ...)
{
static char buf [1024] = "";

va_list arg; va_start (arg, format);
_vsnprintf_s (buf, sizeof (buf) - 1, _TRUNCATE, format, arg);
va_end (arg);

OutputDebugString (buf);
printf ("%s", buf);
}

//--------------------------------------------------------------------------------------------------

int main()
{
OutputDebugPrintf ("\n%s(): Start\n", __func__);

AddVectoredExceptionHandler (1, VectoredExceptionHandler);

struct meow_exception { int code = 3; };

try
{
throw meow_exception();
}

catch (const meow_exception& e)
{
OutputDebugPrintf ("\n%s(): catch (meow_exception { %d })\n", __func__, e.code);
}

catch (...)
{
OutputDebugPrintf ("\n%s(): catch (...)\n", __func__);
}

OutputDebugPrintf ("\n%s(): End\n", __func__);
return 0;
}


Build options:

// Microsoft (R) C/C++ Optimizing Compiler Version 19.00.24213.1 (part of VS 2015 SP3)

cl /c code.cpp /EHsc /W4
link code.obj kernel32.lib /machine:x86 /subsystem:console /debug


Thank you in advance for the answers and advices.

Ded Ded
Answer

To solve this problem I gone deeper with the research and discovered some interesting things concerning MSVC 64-bit mode. I've found that we can not rely on internal compiler-predefined types in 64-bit mode because some of them are wrong.

I compared definitions of some internal structures predefined by the compiler, such as _ThrowInfo and _CatchableType, with assembly listings produced by the compiler being run with /FAs command-line switch.

Here are the instances of these structures extracted from the assembly files (below is MSVC 2015 64-bit version):

;---------------------------------------------------------------------------------------
; Listing generated by Microsoft Optimizing Compiler Version 19.00.24213.1 
; Simplified: many lines skipped, some sections reordered etc -- Ded
;---------------------------------------------------------------------------------------

main proc

;   struct meow_exception { int code = 3; };
;   
;   try
;       {
;       throw meow_exception();

    ...
    lea  rdx, OFFSET FLAT:_TI1?AUmeow_exception@?1??main@@YAHXZ@  ; lea &_ThrowInfo
    lea  rcx, QWORD PTR $T1[rsp]
    call _CxxThrowException

;---------------------------------------------------------------------------------------
_TI1?AUmeow_exception@?1??main@@YAHXZ@                            ; _ThrowInfo
    DD  0
    DD  0
    DD  0
    DD  imagerel _CTA1?AUmeow_exception@?1??main@@YAHXZ@          ; &_CatchableTypeArray

;---------------------------------------------------------------------------------------
_CTA1?AUmeow_exception@?1??main@@YAHXZ@                           ; _CatchableTypeArray
    DD  1
    DD  imagerel _CT??_R0?AUmeow_exception@?1??main@@YAHXZ@@84    ; &_CatchableType

;---------------------------------------------------------------------------------------
_CT??_R0?AUmeow_exception@?1??main@@YAHXZ@@84                     ; _CatchableType
    DD  0
    DD  imagerel ??_R0?AUmeow_exception@?1??main@@YAHXZ@@8        ; &_TypeDescriptor
    DD  0
    DD  0ffffffffh
    ORG $+4
    DD  04h
    DD  0

;---------------------------------------------------------------------------------------
??_R0?AUmeow_exception@?1??main@@YAHXZ@@8         ; _TypeDescriptor (aka std::type_info)
    DQ  FLAT:??_7type_info@@6B@
    DQ  0
    DB  '.?AUmeow_exception@?1??main@@YAHXZ@', 0  ; Mangled type name

;---------------------------------------------------------------------------------------

The binary layout of 32-bit version of these structures is similar to 64-bit, with some little differences (FLAT modifier instead of imagerel in address fields and DD instead of DQ in _TypeDescriptor).

Then, let's compare this listing to the predefined types taken from ehdata.h file (f.e., see well-known source by Geoff Chappell or C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\crt\src\ehdata.h file in MSVC 2013; unfortunately this file doesn't exist in MSVC 2015 runtime sources):

typedef const struct _s__ThrowInfo
    {
    unsigned int         attributes;
    _PMFN                pmfnUnwind;            // this is a pointer!
    int (__cdecl        *pForwardCompat) (...); // this is a pointer too!
    _CatchableTypeArray *pCatchableTypeArray;   // this is a pointer too!
    }
    _ThrowInfo;

typedef const struct _s__CatchableType
    {
    unsigned int     properties;
    _TypeDescriptor *pType;                     // this is a pointer too!
    _PMD             thisDisplacement;
    int              sizeOrOffset;
    _PMFN            copyFunction;              // this is a pointer too!
    }
    _CatchableType;

In 32-bit mode, everything is OK because pointers are 32-bit and predefined internal definitions of structures correspond with assembly listings.

In 64-bit mode, pointers in these structures are RVAs (Relative Virtual Addresses) measured from image base of the module. This is known and well-documented feature; it truly corresponds with assembler listing above. Notice imagerel address modifiers, these mean RVAs. These RVAs are 32-bit and defined as 32-bit DD keyword.

But in 64-bit mode, from the C++ side, the corresponding pointers are considered to be 64-bit. Thus, C++ binary layout of the internal compiler structures containing pointers (such as _ThrowInfo or _CatchableType above) does not correspond to the Assembler binary layout. Sizes of these structures are greater from C++ side, and the fields offsets are wrong too.

To test this, I defined my own custom structures with the same fields represented as 32-bit integer types instead of pointers:

namespace CORRECT
    {
    struct ThrowInfo
        {
        __int32 attributes;
        __int32 pmfnUnwind;           // now this is 32-bit RVA
        __int32 pForwardCompat;       // now this is 32-bit RVA
        __int32 pCatchableTypeArray;  // now this is 32-bit RVA
        };

    struct CatchableType
        {
        __int32 properties;
        __int32 pType;                // now this is 32-bit RVA
        _PMD    thisDisplacement;
        __int32 sizeOrOffset;
        __int32 copyFunction;         // now this is 32-bit RVA
        };
    }

Then I dumped the contents of _ThrowInfo and _CatchableType using both internal definitions and my own definitions. Here's the result (MSVC 2015 64-bit):

exc->ExceptionCode               = 0xE06D7363
exc->ExceptionAddress            = 0x000007FEFD69A06D
exc->NumberParameters            = 4
exc->ExceptionInformation[0]     = 0x0000000019930520 (sig)
exc->ExceptionInformation[1]     = 0x00000000002BF8B0 (object)
exc->ExceptionInformation[2]     = 0x000000013F9C4210 (throwInfo)
exc->ExceptionInformation[3]     = 0x000000013F950000 (module)

Built-in: _ThrowInfo, size 28
_throwInfo->attributes           = 0x00000000 [ofs:  0, size: 4, type: unsigned int]
_throwInfo->pmfnUnwind           = 0x00000000 [ofs:  4, size: 8, type: void (__cdecl*)(void * __ptr64)]
_throwInfo->pForwardCompat       = 0x00074230 [ofs: 12, size: 8, type: int (__cdecl*)(void)]
_throwInfo->pCatchableTypeArray  = 0x00000000 [ofs: 20, size: 8, type: struct _s__CatchableTypeArray const * __ptr64]

Custom: CORRECT::ThrowInfo, size 16
throwInfo->attributes            = 0x00000000 [ofs:  0, size: 4, type: int]
throwInfo->pmfnUnwind            = 0x00000000 [ofs:  4, size: 4, type: int]
throwInfo->pForwardCompat        = 0x00000000 [ofs:  8, size: 4, type: int]
throwInfo->pCatchableTypeArray   = 0x00074230 [ofs: 12, size: 4, type: int]

throwInfo->pCatchableTypeArray   = 0x0000000000074230
cArray                           = 0x000000013F9C4230

Built-in: _CatchableType, size 36
_cType->properties               = 0x00000000 [ofs:  0, size: 4, type: unsigned int]
_cType->pType                    = 0x00075D58 [ofs:  4, size: 8, type: struct _TypeDescriptor * __ptr64]
_cType->thisDisplacement.mdisp   = 0xFFFFFFFF [ofs: 12, size: 4, type: int]
_cType->thisDisplacement.pdisp   = 0x00000000 [ofs: 16, size: 4, type: int]
_cType->thisDisplacement.vdisp   = 0x00000004 [ofs: 20, size: 4, type: int]
_cType->sizeOrOffset             = 0x00000000 [ofs: 24, size: 4, type: int]
_cType->copyFunction             = 0x00000000 [ofs: 28, size: 8, type: void (__cdecl*)(void * __ptr64)]

Custom: CORRECT::CatchableType, size 28
cType->properties                = 0x00000000 [ofs:  0, size: 4, type: int]
cType->pType                     = 0x00075D58 [ofs:  4, size: 4, type: int]
cType->thisDisplacement.mdisp    = 0x00000000 [ofs:  8, size: 4, type: int]
cType->thisDisplacement.pdisp    = 0xFFFFFFFF [ofs: 12, size: 4, type: int]
cType->thisDisplacement.vdisp    = 0x00000000 [ofs: 16, size: 4, type: int]
cType->sizeOrOffset              = 0x00000004 [ofs: 20, size: 4, type: int]
cType->copyFunction              = 0x00000000 [ofs: 24, size: 4, type: int]

cArray->arrayOfCatchableTypes[0] = 0x0000000000074240
cType                            = 0x000000013F9C4240

cType->pType                     = 0x0000000000075D58
type                             = 0x000000013F9C5D58

type->name()                     = "struct `int __cdecl main(void)'::`2'::meow_exception"
cType->sizeOrOffset              = 4

See the differences in sizes of the whole structures (28 vs 16 bytes, 36 vs 28 bytes), of the pointer members (8 vs 4 bytes) and wrong offsets.

When using CORRECT:: definitions, it's easy to get correct RTTI desired.

The original C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\crt\src\ehdata.h file from MSVC 2013 runtime sources contains conditional preprocessor directives #ifdef _EH_RELATIVE_OFFSETS which substitute pointers to __int32 offsets. But predefined internal compiler types always contains 64-bit wrong pointers.

Thus, using internal definitions of RTTI structures are unreliable in 64-bit mode. One should use its own definitions where pointer members are represented as 32-bit integers (or #define _EH_RELATIVE_OFFSETS and use ehdata.h mentioned above). After that, don't forget manually convert RVAs to the common C++ pointers by adding ImageBase address as usual. But one should not trust pointer members in such structures and definitions containing such pointers because they don't reflect the true 64-bit binary layout.

I tested it with MSVC 2010, and got the same results.

Here's the code for getting correct RTTI in 64-bit MSVC environment:

#include <stdio.h>
#include <typeinfo>
#include <stdexcept>
#include <windows.h>

//------------------------------------------------------------------------------------------------------------------------------
//! These definitions are based on assembly listings produded by the compiler (/FAs) rather than built-in ones
//! @{

#pragma pack (push, 4)

namespace CORRECT
    {

    struct CatchableType
        {
        __int32 properties;
        __int32 pType;
        _PMD    thisDisplacement;
        __int32 sizeOrOffset;
        __int32 copyFunction;
        };

    struct ThrowInfo
        {
        __int32 attributes;
        __int32 pmfnUnwind;
        __int32 pForwardCompat;
        __int32 pCatchableTypeArray;
        };

    }

#pragma pack (pop)

//! @}
//------------------------------------------------------------------------------------------------------------------------------

const unsigned EXCEPTION_CPP_MICROSOFT                  = 0xE06D7363,  // '?msc'
               EXCEPTION_CPP_MICROSOFT_EH_MAGIC_NUMBER1 = 0x19930520,  // '?msc' version magic, see ehdata.h

               EXCEPTION_OUTPUT_DEBUG_STRING            = 0x40010006,  // OutputDebugString() call
               EXCEPTION_THREAD_NAME                    = 0x406D1388;  // Passing name of thread to the debugger

void OutputDebugPrintf (const char* format, ...);

//------------------------------------------------------------------------------------------------------------------------------

long WINAPI VectoredExceptionHandler (EXCEPTION_POINTERS* pointers)
    {
    const EXCEPTION_RECORD* exc = pointers->ExceptionRecord;

    if (exc->ExceptionCode == EXCEPTION_OUTPUT_DEBUG_STRING ||
        exc->ExceptionCode == EXCEPTION_THREAD_NAME)
        return EXCEPTION_CONTINUE_SEARCH;

    OutputDebugPrintf ("\n%s(): Start\n\n", __FUNCTION__);

    OutputDebugPrintf         ("exc->ExceptionCode               = 0x%X\n", exc->ExceptionCode);
    OutputDebugPrintf         ("exc->ExceptionAddress            = 0x%p\n", exc->ExceptionAddress);

    if (exc->ExceptionInformation[0] == EXCEPTION_CPP_MICROSOFT_EH_MAGIC_NUMBER1 && 
        exc->NumberParameters >= 3)
        {
        OutputDebugPrintf     ("exc->NumberParameters            = %u\n", exc->NumberParameters);

        OutputDebugPrintf     ("exc->ExceptionInformation[0]     = 0x%p (sig)\n",       (void*) exc->ExceptionInformation[0]);
        OutputDebugPrintf     ("exc->ExceptionInformation[1]     = 0x%p (object)\n",    (void*) exc->ExceptionInformation[1]);
        OutputDebugPrintf     ("exc->ExceptionInformation[2]     = 0x%p (throwInfo)\n", (void*) exc->ExceptionInformation[2]);

        if (exc->NumberParameters >= 4)
            OutputDebugPrintf ("exc->ExceptionInformation[3]     = 0x%p (module)\n",    (void*) exc->ExceptionInformation[3]);

        OutputDebugPrintf ("\n");

        HMODULE module = (exc->NumberParameters >= 4)? (HMODULE) exc->ExceptionInformation[3] : NULL;

        #define RVA_TO_VA_(type, addr)  ( (type) ((uintptr_t) module + (uintptr_t) (addr)) )

        const         _ThrowInfo* _throwInfo = (const         _ThrowInfo*) exc->ExceptionInformation[2];
        const CORRECT::ThrowInfo*  throwInfo = (const CORRECT::ThrowInfo*) exc->ExceptionInformation[2];

        #define DUMP_(var, struc, field)  OutputDebugPrintf ("%-32s = 0x%08X [ofs: %2u, size: %u, type: %s]\n",  \
                                                             #var "->" #field, (var)->field,                 \
                                                             offsetof (struc, field), sizeof ((var)->field), \
                                                             typeid ((var)->field) .name());
        if (_throwInfo)
            {
            OutputDebugPrintf ("Built-in: _ThrowInfo, size %u\n", sizeof (_ThrowInfo));
            DUMP_ (_throwInfo, _ThrowInfo, attributes);
            DUMP_ (_throwInfo, _ThrowInfo, pmfnUnwind);
            DUMP_ (_throwInfo, _ThrowInfo, pForwardCompat);
            DUMP_ (_throwInfo, _ThrowInfo, pCatchableTypeArray);
            OutputDebugPrintf ("\n");
            }
        else
            OutputDebugPrintf ("_throwInfo is NULL\n");

        if (throwInfo)
            {
            OutputDebugPrintf ("Custom: CORRECT::ThrowInfo, size %u\n", sizeof (CORRECT::ThrowInfo));
            DUMP_ ( throwInfo, CORRECT::ThrowInfo, attributes);
            DUMP_ ( throwInfo, CORRECT::ThrowInfo, pmfnUnwind);
            DUMP_ ( throwInfo, CORRECT::ThrowInfo, pForwardCompat);
            DUMP_ ( throwInfo, CORRECT::ThrowInfo, pCatchableTypeArray);
            OutputDebugPrintf ("\n");
            }
        else
            OutputDebugPrintf ("throwInfo is NULL\n");

        if (throwInfo)
            {              
            const _CatchableTypeArray* cArray = RVA_TO_VA_(const _CatchableTypeArray*, throwInfo->pCatchableTypeArray);

            OutputDebugPrintf ("throwInfo->pCatchableTypeArray   = 0x%p\n",   (void*)(ptrdiff_t) throwInfo->pCatchableTypeArray);
            OutputDebugPrintf ("cArray                           = 0x%p\n\n", (void*)            cArray);

            const         _CatchableType* _cType = RVA_TO_VA_(const         _CatchableType*, cArray->arrayOfCatchableTypes[0]);
            const CORRECT::CatchableType*  cType = RVA_TO_VA_(const CORRECT::CatchableType*, cArray->arrayOfCatchableTypes[0]);

            OutputDebugPrintf ("Built-in: _CatchableType, size %u\n", sizeof (_CatchableType));
            DUMP_ (_cType, _CatchableType, properties);
            DUMP_ (_cType, _CatchableType, pType);
            DUMP_ (_cType, _CatchableType, thisDisplacement.mdisp);
            DUMP_ (_cType, _CatchableType, thisDisplacement.pdisp);
            DUMP_ (_cType, _CatchableType, thisDisplacement.vdisp);
            DUMP_ (_cType, _CatchableType, sizeOrOffset);
            DUMP_ (_cType, _CatchableType, copyFunction);
            OutputDebugPrintf ("\n");

            OutputDebugPrintf ("Custom: CORRECT::CatchableType, size %u\n", sizeof (CORRECT::CatchableType));
            DUMP_ ( cType, CORRECT::CatchableType, properties);
            DUMP_ ( cType, CORRECT::CatchableType, pType);
            DUMP_ ( cType, CORRECT::CatchableType, thisDisplacement.mdisp);
            DUMP_ ( cType, CORRECT::CatchableType, thisDisplacement.pdisp);
            DUMP_ ( cType, CORRECT::CatchableType, thisDisplacement.vdisp);
            DUMP_ ( cType, CORRECT::CatchableType, sizeOrOffset);
            DUMP_ ( cType, CORRECT::CatchableType, copyFunction);
            OutputDebugPrintf ("\n");

            OutputDebugPrintf ("cArray->arrayOfCatchableTypes[0] = 0x%p\n",   (void*) cArray->arrayOfCatchableTypes[0]);
            OutputDebugPrintf ("cType                            = 0x%p\n\n", (void*) cType);

            const std::type_info* type = RVA_TO_VA_(const std::type_info*, cType->pType);

            OutputDebugPrintf ("cType->pType                     = 0x%p\n",   (void*)(ptrdiff_t) cType->pType);
            OutputDebugPrintf ("type                             = 0x%p\n\n", (void*)            type);

            OutputDebugPrintf ("type->name()                     = \"%s\"\n", type->name());
            OutputDebugPrintf ("cType->sizeOrOffset              = %u\n\n",   (unsigned) cType->sizeOrOffset);

            }

        #undef DUMP_
        #undef RVA_TO_VA_
        }

    OutputDebugPrintf ("%s(): End\n", __FUNCTION__);
    return EXCEPTION_CONTINUE_SEARCH;
    }

//------------------------------------------------------------------------------------------------------------------------------

void OutputDebugPrintf (const char* format, ...)
    {
    static char buf [1024] = "";

    va_list arg; va_start (arg, format);
    _vsnprintf_s (buf, sizeof (buf) - 1, _TRUNCATE, format, arg);
    va_end (arg);

    OutputDebugString (buf);
    printf ("%s", buf);
    }

//------------------------------------------------------------------------------------------------------------------------------

int main()
    {    
    OutputDebugPrintf ("\nCompiled with MSVC %d, %d-bit\n", _MSC_VER, 8 * sizeof (void*));
    OutputDebugPrintf ("\n%s(): Start\n", __FUNCTION__);

    AddVectoredExceptionHandler (1, VectoredExceptionHandler);

    struct meow_exception { int code; meow_exception() : code (3) {} };

    try
        {
        throw meow_exception();
        }

    catch (const meow_exception& e)
        {
        OutputDebugPrintf ("\n%s(): catch (meow_exception { %d })\n", __FUNCTION__, e.code);
        }

    catch (...)
        {
        OutputDebugPrintf ("\n%s(): catch (...)\n", __FUNCTION__);
        }

    OutputDebugPrintf ("\n%s(): End\n", __FUNCTION__);
    return 0;
    }