#pragma unmanaged makes vc_redist a must dependency - visual-c++

My MSIX-packaged project uses a hand-made C++ DLL, which requires Visual C++ Runtime (vc_redist) to run, otherwise it will silently crash. I would like to allow users to run it without having to find / install vc_redist by themselves.
I did find people mentioning that including VCLibs as a dependency in the MSIX package manifest thing, but it didn't work for my project for some reason. I assume in some part of the code it is explicitly targeting the runtime from vc_redist.
Here is the project: https://github.com/AkazaRenn/FruitLanguageSwitcher/
The DLL project is inside at here:
https://github.com/AkazaRenn/FruitLanguageSwitcher/tree/main/Core/LanguageSwitcher
I can be certain that this DLL project is the issue, with this part removed the project would start with no problems.
Any help is greatly appreciated, thanks in advance!
Update: Did a lot of tests and found it's related to the #pragma unmanaged piece I put on the DLL. Didn't think too much about it since it seemed to be working, but actually it has an impact. I've changed it into a more precise way and seems fine now. Would like any explanation on such behavior.

Related

Missing .dll error reoccurence

I have a question regarding VC++ 5.0.
For a dialog-based project I am writing, I have linked it to a particular dynamic link library called File32.dll by adding the corresponding .lib file to my project debug folder as you do.
I also linked to this library in the Project Settings. This library contains functions specific to a particular application which I need to access. All of the necessary header files have been included and the project builds without errors or warnings.
The problem is that once I try to debug and run the dialog, an error appears:
The program can't start because OUTPUT.dll is missing from your
computer.Try reinstalling the program to fix this problem.
OUTPUT.dll is a library I am not linking to for this project. And when I add this particular .dll to my debug folder, the same error appears with a different .dll (SYSINT32.dll).
No matter how much I add these dlls to my debug folder, the error message reappears with a new dll. Bare in mind, the project debugged and ran successfully before I linked to File32.lib. So I feel that the problem lies with File32.lib. Any ideas on what might be happening with the linker?
Use Dependency Walker to open your File32.dll. It will show all DLLs this one (statically) depends on. It will also highlight the missing ones.
As for VC++ 5.0 ... I feel the need to comment ...
Visual C++ 5.0, which included MFC 4.21 and was released 1997-04-28 (...)
that's an amazing 18 years :-)

Visual Studio 2010 C++/CLI in Static Library Mode: could not find assembly 'mscorlib.dll'

I am working on a C++/CLI project with VS 2012 in Dynamic Library (.dll) and x64 mode.
If I switch the mode to Static Library, I get the error below.
Error 1 error C1107: could not find assembly 'mscorlib.dll': please specify the assembly search path using /AI or by setting the LIBPATH environment variable C:\Depot\Main\Current\Sln\ALibraryProject\Stdafx.cpp 1 1 ALibraryProject
I tried removing the reference to the mscorlib.dll then adding it again from:
Project > Properties > General > Common Properties
But that didn't help. As I know that VS handles the reference to the .NET assemblies, I don't want to add a disk file reference to it as it seems illogical! Did anybody face this before?
I had the same problem when converting my solution from the VS2010 compiler to VS2013 compiler.
I resolved it by changing the project settings (for the project containing the managed .cpp file that was throwing this error) as follows: In Project Settings | C/C++ | General | Additional #using Directories I added the macro $(FrameworkPathOverride). This resolves to the reference assembly directory for the version of .NET that you're targeting, which in my case is C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework.NETFramework\v4.5.1
If I switch the mode to Static Library
This is not the typical error you get when you try to build a static library with /clr in effect. I'd have to assume you've been tinkering with project settings to get rid of the inscrutable linker errors you get when you try to do this.
Core issue is that the C++/CLI build system doesn't support static libraries that contain MSIL. Managed code doesn't use a linker, binding happens at runtime. Which makes the essential difference between static libraries and DLLs disappear. So Microsoft decided to not support it because it didn't make much sense to implement it. Unfortunately they don't yell loud enough when you try to do it anyway, the linker errors you get don't give enough of a hint what you did wrong. Workarounds, like merging with ILMerge don't work either, it cannot deal with mixed-mode assemblies. Merging the native code sections and their associated relocation table entries is very untrivial.
Keep in mind that it is fine to link native static libraries. A typical C++/CLI project has only the ref class wrappers that need to be built with /clr in effect. You can glue any amount of native code from libraries into the final assembly.
I'm forced to theorize about the actual compile error, too many programmers get this error for another reason that doesn't have anything to do with building static libraries and they are harassing me in the comments.
Do beware that targeting a different version of .NET than the one you have installed on your machine is quite a hazardous affair, particularly so if you want to target 4.0 and you have 4.5.x installed. The key element in your .vcxproj file is the <TargetFrameworkVersion>. This will be missing if you started the project targeting an old .NET version, you have to insert it yourself. The IDE also doesn't support changing it if it is present, again edit by hand.
Which is enough to coax MSBuild into generating the proper compile command. You can verify if that panned-out well, look in the *.tlog subdirectory of the Debug build directory for your project. The cl.command.1.tlog file shows the options that were passed to the compiler. It should contain:
/AI"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework.NETFramework\v4.0"
/FU"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework.NETFramework\v4.0\mscorlib.dll"
Note the subdirectory, very important that it matches your intended .NET target. v4.0 in this example. And very, very important that it does not point to c:\windows\microsoft.net, the legacy location for reference assemblies.
I have the same problem. Having a dll doesn't work, as I need to provide a native C++ wrapper for a .net object so it can fulfil a natice c++ interface - I can't use .net in a dll interface - this gives a compile error
This worked as a static library in VS 2010 (with .net 4)
Some of my executables and dlls which also have some code with /clr. They don't have an issue. I'm not trying to make a net Lbirary.
I solved it by removing dependency in old and not updated mixed lib, which was also configured only in Debug configuration, and as result, it started to get the same error as yours after I changed some code.
It was not simple to find it, because error is not clear, and the dependency was set up via "Additional Dependencies" in project settings.
Open visual studio and unload your project then Go to the project folder and open file .vcxproj . Search for tag "targetFrameworkVersion"
(if not present it means ur project is not using dot net frameworks.so no requirement of change)
Change it to required version
Save the file.
And now reload the project .

vld_x86 dll not found error shown when i try to run the debug mode of the application

i am new in using the Visual Leak Detector, after creating the settings as per the documentations for Visual C++ 6, and running the program in the debug mode
the error
"The application has failed to start because vld_x86.dll was not found.Re-installing the application may fix this problem"
i have reinstalled and included the path for the dll in the VC6 settings.
thanks in advance for the help.
After searching for the answer myself for quite a long time, two things finally corrected the problem for me. First, if you haven't already restarted Visual Studio after including these new files and libraries, then you should do so. Second, when I went to look into my computer to see what was added to my path in environment variables, it had add the win64. and I run win32. Hope that was descriptive enough and helps.
the include is correct and needed as far as i know.
i was having the same problem and could solve it by copying all files in vld's "bin" directory into the same folder as the executable i wanted to check for leaks.
not a very elegant way but working, i hope it works for you aswell!

LoadLibrary Module Not Found - DLL Hell After Office 2007 Install

Unfortunately this is going to be a pretty open-ended question, but I am at my wit's ends and I thought I would reach out for some advice.
This is a Visual C++ MFC app using Visual Studio 2008 SP1.
A coworker and I both had Office 2007 installed and we have both had strange DLL loading problems with our app since. Specifically, LoadLibrary is failing to load one our DLLs ( the first one it loads ) and returning error code 126 ( module not found ). What's really strange is that if I just run the executable from the windows explorer it works fine.
I took the usual steps to diagnose the problems:
Verify that the file existed and that the current working directory was pointed at it.
Run dependency walker and verify that it's dependencies are loading correctly. They are all loading ok except the ones this question says are ok to fail.
Experiment with loading some different DLLs at the same location in the code. Some of the simple 'stub' dlls succeed, but most of them fail.
Experiment with loading the DLLs that are failing from separate test apps - in an empty console app and a barebone MFC app, all the DLLs are loading fine!
Try to load the DLLs with LoadLibraryEx and the LOAD_LIBRARY_AS_DATAFILE flag, which does succeed but doesn't get us very far except to point out it's probably a dependency problem.
I really don't know what else to do at this point. Like I said, Office 2007 is a common thread in our problem but I don't know what kind of problems it could create. I really don't know even what steps to take next. Any ideas?
edit: I'm pretty sure the current working directory is not in the DLL path for some reason. It seems the DLLs that are failing are ones that need any other DLLs. If I turn on Loader Snaps debug output the current working directory does not appear to be in the DLL loading path. Any idea what could cause this?
edit2: The current build dumped the executable into a directory other than the working directory. For some reason, when I tried to load a DLL which then tried to load ANOTHER DLL, the current working directory is no longer searched. By putting the executable into the directory with all of the DLLs I am trying to load, the problems go away. Based on all of this, and the output by loader snaps, I am 98% sure this is some bizarre Visual Studio bug and I will simply have to work around it.
Office 2007 turns on SafeDllSearchMode in the registry.
http://msdn.microsoft.com/en-us/library/ms682586%28VS.85%29.aspx
With SafeDlLSearchMode, the current directory is no longer searched. To disable it, they claim you can go into regedit and set HKLM/System/CurrentControlSet/Control/SessionManager/SafeDllSearchMode to 0, but this did not work for me. Calling SetDllDirectory to the current directory DID work for me, although this only works if you are targeting XP SP1+.
The reason this caused problems in my specific app is that when we run the executable from the debugger, we keep the executable in a different directory than the current directory with all the other build files. When we run outside of Visual Studio, we first copy the executable into the directory with all of the other DLLs. The directory that the original executable is called from is ALWAYS in the search path, so if you keep your executable and your dlls together, you would never run into this problem.
Still, it's quite confusing for Microsoft to change the dll search path under us like this.
Does the DLL which fails has MSVCRT80 in dependencies? If yes, the most likely reason is that Office 2007 has overridden MSVCR80.dll

Why my App's Dll is not loading in win2000 and loading in XP

We have an installer application.
In that we have one dll related to our application.
We created setup with all respective files.
We used "Install Shield 6.3" and created a setup file.
After created build. The build is working in xp, not working in 2000.
It is showing error message as Couldn't load .dll only in win2000.
What could be the issue any idea?
Regards
Hara
It looks like one of the system/third party dll you are loading is either not available or of wrong version. Use a tool like dependency walker to check whether all the required dlls are available or not.
You have probbely missing prequsits that exits on XP but not on Win2000.
You need to run the Dependency Walker tool on Win2000 and load the problematic DLL, the tool will tell what is missing.
Try running installation with Filemon in the background, filtering with the missing DLL's name. Then, see where the DLL is searched for, and fix the problem. Hard to say without any further information, but first difference I have in mind is that the system folder in XP is C:\windows\system32, while in win2000 it is C:\winnt\system32. If you've hardcoded the system path for any reason, it might be the problem.

Resources