I am creating a C++/CLI dll that will be loaded into a legacy c++ application. The legacy application does this with a traditional call to LoadLibrary. Both the application and the C++/CLI dll are compiled in 64 bit mode.
When the LoadLibrary call happens, it fails with error 193. This usually means that some non-64bit component is trying to load. When I look at the dll load output in visual studio 2010, I see the the failure is occurring when mscoree.dll is being loaded (to be exact, I see my dll loaded, then mscoree loaded, then mscoree unloaded, then my dll unloaded, then the error returned). Specifically C:\Windows\System32\mscoree.dll is being loaded, when I examine this mscoree.dll, I find that it is targeting I386.
How can I ensure that my application will link against the correct mscoree.dll? I understand this could be done with a manifest, but I can't find any good information about setting one up. The ideal solution would allow compilation in 32bit or 64bit mode and target the correct mscoree.dll.
As a side note, I found an mscoree.dll in a side-by-side folder that I verified is 64bit mode and copied it into my application directory with the hopes that it would pick up that one first. This didnt work and the C:\Windows\System32 version was still loaded.
Thanks,
Max
Output of CorFlags.exe on the C++/CLI dll
Microsoft (R) .NET Framework CorFlags Conversion Tool. Version 4.0.30319.1
Copyright (c) Microsoft Corporation. All rights reserved.
Version : v4.0.30319
CLR Header: 2.5
PE : PE32+
CorFlags : 16
ILONLY : 0
32BIT : 0
Signed : 0
Output of pedump.exe on C:\System32\mscoree.dll
PS C:\Windows\System32> pedump.exe .\mscoree.dll
Dump of file .\MSCOREE.DLL
File Header
Machine: 014C (I386)
Number of Sections: 0004
TimeDateStamp: 4B90752B -> Thu Mar 04 22:06:19 2010
PointerToSymbolTable: 00000000
NumberOfSymbols: 00000000
SizeOfOptionalHeader: 00E0
Characteristics: 2102
EXECUTABLE_IMAGE
32BIT_MACHINE
DLL
...
(pedump goes on from here to describe imports and exports but thats not important here)
Extended loading information
This is the full output from failed load.
Note: The C++/CLI dll is called DsfClr.dll
the output was obtained by running gflags.exe -i [exename] +sls and examining the results in a debugger
http://pastebin.com/FyumUiMN
UPDATE:
Using a tip posted in a below comment by Reuben, I was able to determine that mscoree.dll is indeed targeting AMD64, but pedump is providing invalid information because it is being run in WOW64. That being said I still cannot load this library, if anyone has any suggestions they would be greatly appreciated.
One more thing I have tried: I made a new C# application and referenced the C++/CLI dll, then, in the main() function, I instantiated a class in the C++/CLI dll. This caused an access violation exception before the main() function is called. When I remove the instantiation, the main function runs fine. My guess is that the instantiation is causing a delay load of my C++/CLI assembly, which causes the same load error I was seeing from the native assembly.
In case anyone runs across this error, it turned out that it was caused by my native libraries use of boost::threading. The boost::threading library uses some weird compilation settings. The result is a static library that is incompatible with clr or mixed-mode binaries. Of course, visual studio has no idea of this, so it happily links boost in and crashes when the dll is loaded.
The solution is to dynamically link in boost::threading. The easiest way to do this is to define BOOST_THREAD_DYN_LINK in your project settings. Once I defined that, the dll loaded fine.
A quick google search of C++/CLI boost threading will give plenty more information about this error
I just has a similar scenario.
LoadLibrary failed with 193.
My DLL is a managed C++/CLI DLL called from a native application with LoadLibrary.
However I only get the error on win7 systems. It loads fine on win10. The date of this original question suggests it was win7.
I narrowed it down to a thread_local class.
It appears win7 only supports basic types such as C pointers as thread_local. Anything more complex, even std::shared_ptr which win10 accepts, generates error 193 on Dll load.
For the record, the compiler is VS2015, and the code style is c++11.
Related
I've dynamically linked libhunspell.dll (HunSpell) to my application. It works, but there is a dumb problem which I don't know why it happens.
Even before I use LoadLibrary("path\\to\\libhunspell.dll"); to load it and use it, on the start of the application it attempts to load the library by itself. If I place the libhunspell.dll into the path where my main executable resides, it can load it, otherwise it reports an error, immediately after starting the application - This application has failed to start because LIBHUNSPELL.DLL was not found. Re-installing the application may fix this problem. and the application doesn't start.
I would understand if the LoadLibrary would use invalid path but this happens as soon as the executable runs, even before the first statement in WINAPI _tWinMain(HINSTANCE, HINSTANCE, LPTSTR, int) executes (I've tried to place a breakpoint and it doesn't even reach it, so this happens before).
So, as a result, I must place libhunspell.dll in the same folder as my application executable, and not in the path I want.
This is probably easy to fix although I don't what to look for.
So the question is - how do I avoid it loading it immediately and have it wait until I use LoadLibrary call?
Here is how I linked if it can help:
1) compiled libhunspell.dll in Visual Studio 2015 (I used /MT option to link it statically so it doesn't have VC++ Redistributable as a dependency).
2) created import library (libhunspell.lib) using implib.exe -a -c -f libhunspell.lib libhunspell.dll
3) linked that to the source .cpp unit which is using it using #pragma comment(lib, "libhunspell.lib") (it is RAD Studio 2010 so the .lib is required unlike newer versions).
4) later in the same .cpp used LoadLibrary to load this library and used it.
By linking in the import stubs (libhunspell.lib) the OS will load the DLL for you as it is now a static dependency.
One approach would be specify the library as a delayload dependency: /DELAYLOAD:libhunspell.lib via the linker options. You can then call LoadLibrary on the DLL.
The only other option is to stop including the .lib in the linker step, making it truly a dynamic dependency.
I assume you did Add to project a *.lib file for your DLL. That is a kind of "static" linkage done in the App initialization (prior to your forms are created). So it has two disadvantages.
You DLL must be in the same path as the Apps EXE file
Sometimes DLL file name is locked (can not be changed)
The advantage is that you do not need to do any coding for the DLL loading as the VCL do it for you ... so your app should not contain the LoadLibrary,GetProcAddress calls you just include the *.h file with propper import declarations ...
For dynamic linkage you need to remove the *.lib from your project and use WinAPI LoadLibrary + GetProcAddress for loading your DLL as josh poley suggested. Here an example:
Builder C++ calling VC++ class
Beware there was/(is?) a bug in the GetProcAddress preventing from loading all the functions from your DLL in some cases. Especially if the DLL has old legacy mangling of names the count of functions is high and the DLL was created on compiler incompatible with the mangling in question.
I'm trying to get TFS team-build to reliably build a WPF C# app. This app relies on a VB6Lib.dll which we maintain, this VB6Lib.dll itself relies on other C# libs that we also maintain.
I've set up a build definition to build (in order):
VbDependencies.sln (all libs in this have com interop set, thus the VB6 can find their TLBs)
buildVB6Lib.proj (an msbuild file which calls "VB6.exe /make /d" to make the VBLib.dll on the build server, as part of this script I've been copying the VB6Lib.dll output to C:\tmp)
MainApp.sln (in my workspace, I've added a reference to C:\tmp\VB6Lib.dll)
Does this sound ok
?
On my dev laptop I usually build the VB6, copy its output to \tmp and then regsvr32 it there before adding a reference to it in my C# solution. It's this step that I'm not convinced my build def is doing.
Also, is there a way to get more useful output from the VB6 build, currently I get "Compile Error in File 'xxx.bas' Can' find project of library", but not which actual library it can't find.
You are correct in that the critical point in your build process on the development system lies in registering the COM object. However, one does not in general want to register the COM object on the build server, as this can cause all kinds of versioning issues and silent failures when the wrong COM object is registered or the registration fails.
The proper way to accomplish this is to generate an interop assembly manually and reference that instead of the COM object. This is accomplished with the tlbimp utility, for instance:
tlbimp ..\Libraries\VBLib.dll /out:..\Libraries\Interop.VBLib.dll
Run that command on your development system, then remove the reference to VB6Lib.dll and add a reference to Interop.VBLib.dll. You can then add the tlbimp command as a prebuild event in the referencing project so that the interop assembly is always build from the correct version, and you will never again need to have your COM object registered on the build system.
My Problem: I am using Matlab COM Automation Server to call and execute matlab .m files from a VB.Net plugin for a CAD program called Rhino 3D. The code works flawlessly when set up as a simple Windows Application in Visual Studio, but when I insert it (and make the requisite reference) into my .Net plugin and test it in the CAD program I get the following error:
"Could not load file or assembly 'Interop.MLApp, Version 1.0.0.0,
culture=neutral, PublicKeyToken=null' or one of its dependencies.
the system cannot find the file specified."
What I've Tried: I am baffled as to why this occurs, but I was able to contact the CAD program's technical support staff and they suggested that it has something to do with their DotNet SDK having trouble with references that are located far outside the CAD program directory. They didn't have any solutions so I tried playing around with copylocal and this made no difference. I tried using other COM libraries and the Open Office automation server works fine, although uses url's instead of requiring a reference. I also tested Excel, which does require a reference, and it returned the error: "retrieving the COM class factory for component with CLSID {...} failed due to the following error: 80040154." This may or may not be related to the issue with the Matlab COM reference, but I thought was worthwhile to share. Perhaps is there another way to reference Interop.MLApp?
I would appreciate any suggestions or thoughts on how I might make the Matlab Interop.MLApp reference work.
Best regards,
Ben
Try moving the assembly file(s) for MLApp into the bin directory. Based on everything I've read, this seems to be a glitch of some sort during the generation of the assembly binding where all the assemblies are merged together and their locations are assumed. I've included some links where I gleaned a bit of information about it.
http://blogs.msdn.com/isha/archive/2009/04/04/issues-with-wcf-service-when-the-asp-net-website-is-deployed-using-the-web-deployment-project-and-as-non-updatable-project.aspx
ttp://social.msdn.microsoft.com/Forums/en/netfxremoting/thread/30df57a8-2a57-4f9f-a120-30c24bc11681
ttp://social.msdn.microsoft.com/Forums/en/netfxremoting/thread/30df57a8-2a57-4f9f-a120-30c24bc11681
ttp://www.sitefinity.com/support/forums/sitefinity-3-x/bugs-issues/cannot-load-file-or-assembly-error.aspx
ttp://forums.asp.net/t/986130.aspx?PageIndex=8
ttp://stackoverflow.com/questions/408002/could-not-load-file-or-assembly-xxxx-or-one-of-its-dependencies-the-system-can
I have a solution in VS 2008 that creates a DLL. I then use that DLL in another application. If I go in to the DLL projects property pages and change the following configuration for a DEBUG build then the built dll no long provides the desired functionality. If I change it back and rebuild the DLL, then the DLL does provide the correct functionality:
Property Pages => Configuration Properties => C/C++ => Code Generation => Runtime Library
If set to "Multi-threaded Debug DLL (/MDd)"
then everything works as it should. I get the correct functionality from the DLL
If set to "Multi-threaded DLL (/MD)" then the DLL does not function properly...no runtime errors or anything, it just doesn't work (The DLL is supposed to plot some lines on a map but does not in this mode).
So the question is, why does using the /MDd flag result in correction functionality of the underlying code, while /MD results in incorrect functionality?
A little background...somebody else developed the DLL in C++ and I am using this DLL in a VB.net application.
All DLL's/debug code generation must match across everything that uses them. There may be another referenced library or object or dll or some code in there that is built using the wrong options; or specific options for an individual element that override the global project options.
The only way of figuring it out is to meticulously check all of the options for each file, checking the included and referenced libraries (.lib and .dll) and object files. Check the linker options too.
The reason why it doesn't work is probably because the debug version adds extra guard blocks around memory to allow detection of errors.
I had similar problems. My application which "used" a 3rd party DLL crashed when its runtime library was set to "Multi-threaded DLL (/MD)", but worked when its runtime library was set to "Multi-threaded Debug DLL (/MDd)".
It has something to do with passing std::strings and std::lists across the DLL interface.
Our guess was the low level definition of these types was somehow different in the two runtime libraries.
We solved our related problems using this rule...
The DLL and the DLL user must be build using the exact same runtime library.
The main difference between the two options is in the libraries that your code will be linked at later. for the debug version for example this will include LIBCMTD.LIB and a few others. if your library is going to be built as debug the you should always link with MDd. failing to do so will result in lots of unresolved external linker errors at best. and sometimes the code compiles normally but crashes at runtime. if this happens in vb.net then a catch can easily hide the error. I guess you should make sure you build setting is correct. for more detailed information check this.
I have a project which uses C++/CLI to implement a GUI and some background processing to talk to a sensor. I've got that all working and a lot of the comms stuff which we use to communicate the the sensor sits in a .dll. The problem is that I'd like to combine the library into the main executable to avoid having to worry about distributing .dlls.
I've got a demo project which works fine using a .lib but when I try and switch the mani code body to produce a .lib instead of .dll I get the following error:
1>------ Build started: Project: MyTool, Configuration: Debug Win32 ------
1>Compiling...
1>stdafx.cpp
1>.\stdafx.cpp : fatal error C1113: #using failed on 'c:\projects\MyTool\debug\MyLib.lib'
A bit of googling suggests this happens when you've not got the MSIL switch applied, but it's definitely in there in the library project.
I have a mixture of managed and unmanaged code in both my demo project and the real thing so I'm really struggling to see what the problem is here.
Any suggestions would be very gratefully received!
I am guessing a bit, but I suspect the "MyTool" project has the "MyLib" project as one of its "references" ("Project" menu >> Properties >> Common Properties >> References).
When you change the type of the MyLib project to a LIB instead of a DLL, you need to remove "MyLib" from the project references. You then update the project dependencies of the solution ("Project" menu >> "Project Dependencies...") so that MyTool depends on MyLib.
If you are linking to a mixed mode (managed/native) DLL you may get this error. Which you shouldn't if the project uses CLR even if one of the source files doesn't. But anyway, if that is the case, then try removing the reference from Project|Properties|Common Properties|References and then re-adding it.
I also ran into this. The reason it was failing was because I was compiling my native/managed C++ DLL to target .NET 4.0. And the DLL I was #using was a .NET 2.0 DLL. As such it was failing, even though the paths and file names lined up perfectly. In this case the error message was absolutely of no help at all.
I solve it by updating the independent DLL to .NET 4.0. So that both assemblies were using the same .NET framework.