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C1075 error reading tlh file

  • Hi,

    I am trying to access a c# dll from QT using COM. I am able to do this no problem in C++ in visual studio, when I add the same code to QT i get an error when building:

    C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\include\comdef.h:56: error: C1075: end of file found before the left brace '{' at 'c:\users\mypath\myfile.tlh(19)' was matched

    The generated tlh file using QT (with VC++ Compiler 12) appears identical to the tlh file generated by visual studio and there certainly doesn't appear to be a missing brace.

    Unfortunately I am unable to use any compiler other than VC++ Compiler 12 (2013) do to restrictions placed on me by some 3rd party software (Siemens WinCC OA).

    The import line is:
    #import "C:\Users\mypath\myfile.tlb" raw_interfaces_only

    Any suggestions?

    tlh file contents follow:

    // Created by Microsoft (R) C/C++ Compiler Version 12.00.40629.0 (e9f66a42).
    // c:\users\mypath\myclass.tlh
    // C++ source equivalent of Win32 type library C:\Users\mypath\Myclass.tlb
    // compiler-generated file created 02/11/20 at 10:33:06 - DO NOT EDIT!
    // Cross-referenced type libraries:
    //  #import "C:\Windows\Microsoft.NET\Framework64\v4.0.30319\mscorlib.tlb"
    #pragma once
    #pragma pack(push, 8)
    #include <comdef.h>
    namespace MyClass {
    // Forward references and typedefs
    struct __declspec(uuid("7cd620e2-86e5-4de1-95b8-9319b9d4e4d9"))
    /* LIBID */ __MyClass;
    struct /* coclass */ TheClass;
    struct __declspec(uuid("0e01bd9c-c1c5-3f60-9ae2-fd5ddfcdb7ae"))
    /* dual interface */ _TheClass;
    // Smart pointer typedef declarations
    _COM_SMARTPTR_TYPEDEF(_TheClass, __uuidof(_TheClass));
    // Type library items
    struct __declspec(uuid("7dee8be0-f9db-4c27-b407-463a9d67aea6"))
        // [ default ] interface _TheClass
        // interface _Object
    struct __declspec(uuid("0e01bd9c-c1c5-3f60-9ae2-fd5ddfcdb7ae"))
    _TheClass : IDispatch
        // Raw methods provided by interface
          virtual HRESULT __stdcall get_ToString (
            /*[out,retval]*/ BSTR * pRetVal ) = 0;
          virtual HRESULT __stdcall Equals (
            /*[in]*/ VARIANT obj,
            /*[out,retval]*/ VARIANT_BOOL * pRetVal ) = 0;
          virtual HRESULT __stdcall GetHashCode (
            /*[out,retval]*/ long * pRetVal ) = 0;
          virtual HRESULT __stdcall GetType (
            /*[out,retval]*/ struct _Type * * pRetVal ) = 0;
          virtual HRESULT __stdcall GetTheThing (
            /*[in]*/ BSTR arg,
            /*[out,retval]*/ BSTR * pRetVal ) = 0;
    } // namespace MyClass
    #pragma pack(pop)

  • Lifetime Qt Champion

    Hi @Mike10,

    it should not matter if you use the same MSVC compiler from within Visual Studio or Qt Creator, as long as the compiler options are equal. Do note that qmake does set some options by default (like UNICODE) that might lead to different results than in Visual Studio.

    So can you show your .pro file and the compiler call from Compile Output that leads to the given error message?


  • @aha_1980


    Thanks for the reply.

    Pro file contents:

    QT       += core gui
    greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
    TARGET = csharp_import
    TEMPLATE = app
    SOURCES += main.cpp\
    HEADERS  += mainwindow.h
    FORMS    += mainwindow.ui

    cpp file:

    #include "mainwindow.h"
    #include "ui_mainwindow.h"
    #import "C:\Users\mypath\Myclass.tlb" raw_interfaces_only
    MainWindow::MainWindow(QWidget *parent) :
        ui(new Ui::MainWindow)
        CoInitialize(0); // Init COM
        BSTR thing_to_send = ::SysAllocString(L"My thing, or ... ");
        BSTR returned_thing;
        MyClass::_TheClassPtr obj(__uuidof(MyClass::TheClass));
        HRESULT hResult = obj->GetTheThing(thing_to_send, &returned_thing);
        delete ui;

    Compiler output:

    11:13:15: Configuration unchanged, skipping qmake step.
    11:13:15: Starting: "C:\Qt\Qt5.5.1\Tools\QtCreator\bin\jom.exe" 
    	C:\Qt\Qt5.5.1\Tools\QtCreator\bin\jom.exe -f Makefile.Debug
    	cl -c -nologo -FS -Zi -MDd -GR -W3 -w34100 -w34189 -w44996 -EHsc /Fddebug\csharp_import.pdb -DUNICODE -DWIN32 -DQT_LARGEFILE_SUPPORT -DQ_BYTE_ORDER=Q_LITTLE_ENDIAN -DQT_NO_PRINTER -DQT_NO_PRINTDIALOG -DWINAPI_FAMILY=WINAPI_FAMILY_APP -DX64 -D__X64__ -D__x64__ -DQT_WIDGETS_LIB -DQT_GUI_LIB -DQT_CORE_LIB -DQT_OPENGL_ES_2 -DQT_OPENGL_ES_2_ANGLE -I..\csharp_import -I. -I..\..\..\..\Qt\Qt5.5.1\5.5\winrt_x64\include -I..\..\..\..\Qt\Qt5.5.1\5.5\winrt_x64\include\QtWidgets -I..\..\..\..\Qt\Qt5.5.1\5.5\winrt_x64\include\QtGui -I..\..\..\..\Qt\Qt5.5.1\5.5\winrt_x64\include\QtANGLE -I..\..\..\..\Qt\Qt5.5.1\5.5\winrt_x64\include\QtCore -Idebug -I. -I..\..\..\..\Qt\Qt5.5.1\5.5\winrt_x64\mkspecs\winrt-x64-msvc2013 -Fodebug\ @C:\Users\mypath\AppData\Local\Temp\mainwindow.obj.16568.0.jom
    C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\include\comdef.h(56) : fatal error C1075: end of file found before the left brace '{' at 'c:\users\mypath\build-csharp_import-qt_5_5_1_for_windows_runtime_64bit-debug\debug\myclass.tlh(19)' was matched
    jom: C:\Users\mypath\build-csharp_import-Qt_5_5_1_for_Windows_Runtime_64bit-Debug\Makefile.Debug [debug\mainwindow.obj] Error 2
    jom: C:\Users\mypath\build-csharp_import-Qt_5_5_1_for_Windows_Runtime_64bit-Debug\Makefile [debug] Error 2
    11:13:17: The process "C:\Qt\Qt5.5.1\Tools\QtCreator\bin\jom.exe" exited with code 2.
    Error while building/deploying project csharp_import (kit: Qt 5.5.1 for Windows Runtime 64bit)
    When executing step "Make"
    11:13:17: Elapsed time: 00:02.

  • Lifetime Qt Champion

    Hi @Mike10,

    1. It seems you build for Windows RT, is that wanted/correct?
    2. I'd try to place the import in a file that does not include QObject and co. itself. Does it work then?


  • 1)Yes I want to build for windows
    2) No - this made no difference


  • Lifetime Qt Champion

    Hi @Mike10,

    Windows RT != Windows.

    Do you want to build classic Windows API apps or Windows RT = UWP apps?


  • The kits I have are:
    Qt 5.5.1 for windows phone arm MSVC2013 32bit
    Qt 5.5.1 for windows phone x86 MSVC2013 32bit (Emulator)
    Qt 5.5.1 for windows runtime 64bit

    So I chose the last of those.

    I actually want to make a dll for integration with WinCC OA that will also link to a C# library. The first part of this works and I can build a dll that works as a WinCC OA plugin, I am struggling with the 2nd part so created a new project with same settings as the working WinCC OA project.

  • Lifetime Qt Champion

    Hi @Mike10

    none of them are real Windows kits. I'd try to install a Qt MSVC xxxx version (without UWP resp. RT in it).

    If you are not tied to the old Qt versions and compilers, I'd even use a newer one.


  • @aha_1980

    Unfortunately WinCC OA 3.15 requires no later than QT 5.5.1, MSVC 2013 and Win 64bit

    I have downloaded a different file from and that does indeed seem to have resolved the compilation issue :)

    I am now getting an error at runtime but could be something daft so I will look into more.


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