Exception Triggered(read access violation) if QSerialPort instance is created with VECTOR dll(vxlapi.dll)

[lunchtime82]

Hello,

I have struggled with exception problem during few weeks. :(
Please give me some tips for this~

I'm trying to a program that receive GPS data by serial port, and send CAN message using the data.
Development environment is,

• IDE : Qt Creator 3.1.2(based on Qt 5.3.1)
• Qt version : Qt5.3 MSVC2013 32bit
• Compiler : Microsoft Visual C++ compiler 12.0(x86)
• Device type : Desktop(Local PC)

And for device,

• GPS device : ASCEN GPS (GPS742)
  a. This is connected with PC by USB cable.
  b. PC recognize it by serial port(COM12, Baud115200, 8 bit, No parity, one stop bit, No flowControl).
  c. It send GPS data periodically(about 1 second.)
• CAN device : VECTOR CAN/LIN Interface (VN1630)
  a. This is connected with PC by USB cable.
  b. It can control by dll files('vxlapi.h', 'vxlapi.dll', and 'vxlapi.lib')

At first, I made two individual programs,

• 'Receiving & show GPS data' : using 'QSerialPort' class. It works well.
• 'Sending dummy CAN message' : using dll files. It works well.

But when I merged these programs, It compiled well but generated exception error.(read access violation)

For Debug, I made simple console project like below,

[SerialPortControlExample_ref.pro]
@
QT += core
QT += serialport
QT -= gui

TARGET = SerialPortControlExample_ref
CONFIG += console
CONFIG -= app_bundle

TEMPLATE = app

SOURCES += main.cpp

OTHER_FILES +=
vxlapi.lib

HEADERS +=
vxlapi.h

win32: LIBS += -L$$PWD/ -lvxlapi

INCLUDEPATH += $$PWD/
DEPENDPATH += $$PWD/
@

[main.cpp]
@
#include <QtCore/QCoreApplication>
#include <QtCore/QDebug>
#include <QtSerialPort/QSerialPort>
#include <QtSerialPort/QSerialPortInfo>
#include <windows.h>
#include "vxlapi.h"

QT_USE_NAMESPACE

int main(int argc, char *argv[])
{
XLstatus xlStatus;
QCoreApplication a(argc, argv);

//------------ 1st Section --------------------------------------------------
xlStatus = xlOpenDriver();
if(xlStatus == XL_SUCCESS) qDebug() << "Open Success!!";
else qDebug() << "Open Fail!!!";
//------------- End of 1st Section-------------------------------------------

//------------ 2nd Section --------------------------------------------------
// Example use QSerialPortInfo
foreach (const QSerialPortInfo &info, QSerialPortInfo::availablePorts()) {
qDebug() << "Name : " << info.portName();
qDebug() << "Description : " << info.description();
qDebug() << "Manufacturer: " << info.manufacturer();

    // Example use QSerialPort
    QSerialPort serial;
    serial.setPort(info);
    if (serial.open(QIODevice::ReadWrite))
        serial.close();
}

//------------- End of 2nd Section-------------------------------------------

return a.exec();

}
@

[vxlapi.h, vxlapi.lib, vxlapi.dll]

• These files are included 'XL Driver Library 8.3'.
  It can be downloaded at VECTOR site :
  https://vector.com/vi_downloadcenter_en.html?product=xllib&formular_treffer_submit=1
• I copied these files on project directory.

Among above 'main.cpp' file, if one of section is commented out, it is compiled and running correctly.

A. If 1st section is commented out...
[Commannd Window]
@
Name : "COM12"
Description : "GPS USB Serial Interface Driver"
Manufacturer: "Media Tek Inc."
@

B. If 2nd section is commented out,
[Commannd Window]
@
Open Success!!
@

But when I use both section, it is compiled well but generated exception message once I run this program, like below,
[Exception Triggered Window]
@
The inferior stopped because it triggered an exception.
Stopped in thread 0 by: Exception at 0x77a1e066, code: 0xc0000005: read access violation at: 0x0, flags=0x0 (first chance).
@

The debugging result is below,
@
...
Running.
dState changed from EngineRunRequested(7) to InferiorRunOk(11) [master]
ModLoad: 75570000 755d0000 C:\WINDOWS\SysWOW64\IMM32.DLL
ModLoad: 76df0000 76ebc000 C:\WINDOWS\syswow64\MSCTF.dll
(2d4.2558): Access violation - code c0000005 (first chance)

s
sException at 0x77a1e066, code: 0xc0000005: read access violation at: 0x0, flags=0x0 (first chance) in ntdll!RtlAllocateHeap
First chance exceptions are reported before any exception handling.
This exception may be expected and handled.
eax=77280334 ebx=00000000 ecx=00000010 edx=003bf1ec esi=00000000 edi=000000e0
eip=77a1e066 esp=003bee50 ebp=003beebc iopl=0 nv up ei ng nz ac pe cy
cs=0023 ss=002b ds=002b es=002b fs=0053 gs=002b efl=00010297
ntdll!RtlAllocateHeap+0x1c:
77a1e066 8b4344 mov eax,dword ptr [ebx+44h] ds:002b:00000044=????????

*** WARNING: Unable to verify checksum for C:\JayKim\EnS\JaySW\SerialPortControlExample_ref\vxlapi.dll
*** ERROR: Symbol file could not be found. Defaulted to export symbols for C:\JayKim\EnS\JaySW\SerialPortControlExample_ref\vxlapi.dll -
s
sException at 0x77a1e066, code: 0xc0000005: read access violation at: 0x0, flags=0x0 (first chance)
dNOTE: INFERIOR SPONTANEOUS STOP
sStopped.
dState changed from InferiorRunOk(11) to InferiorStopOk(14) [master]
Resolving symbol: ntdll!RtlAllocateHeap...
<x ntdll!RtlAllocateHeap

Obtained 0x77a1e046 for ntdll!RtlAllocateHeap (#1)
<u 0x77a1e046 0x77a1e168
@

Please let me know some tips for these issues.

Thank you.