App deployment error

[Djolas2001]

@kshegunov Is there any solution? I yesterday tried to update both MinGW and Qt, but both have latest versions.

[kshegunov]

@Djolas2001
See my edited answer. I believe you have mismatch in architectures for one, and that you should try tracking the missing dependent symbol in Qt5Core.dll.

[Djolas2001]

@kshegunov Excuse me, I am new in programming, so can you explain me how to try tracking the missing dependent symbol?

[kshegunov]

@Djolas2001

how to try tracking the missing dependent symbol?

I meant finding which dll exports it and what might be the problem with said dll.
I had checked and the dll that exports that particular symbol is libstdc++-6.dll So you should search for the problem there.

I am new in programming

Okay, then. Take a quick glance here so you have at least a basic understanding of the matter. Now to the core:
The .exe has a list of dll files to load, and each of them have a list of their own. So when you start your program there's a special application (in the OS) called the loader that starts transferring the needed dlls to memory, and finally when that's done it does the same for your executable. Only when it's finished your program can actually run.

Your (original) problem is that Qt5Core.dll (used in your application) uses an external function (from another .dll) but that function (or symbol) can't be found by the loader. Those dlls are called dependencies, because Qt5Core.dll can't be loaded before any other .dll it references. What you see with the dependency walker is the dependency tree - the modules (in windows terms) that have to be loaded before your application; and when you expand each of them you see the exported symbols.

At the end of the day, leaving technicalities aside, every single dll must be loaded, and every single symbol found in those loaded dlls for your application to run. Since, the loader can't locate the __cxa_throw_bad_array_new_length symbol your application fails to run. A hint, is that it runs fine inside your IDE, so that means that in all probability you had deployed a wrong dll, or rather wrong combination of dlls. What I suspect happened is that you'd built your application and had shipped dlls from MinGW that are different from those used when Qt was built. Or you have copied 32bit dlls, when 64bit ones are expected.

Probably the cleanest attempt would be to create a new empty folder and carefully copy each of the dlls. Also, make sure that compiler versions match between all the dlls and the application. And don't copy the system dlls - kernel32, msvcrt, shell32 etc. at least until you're convinced your application is working fine without them (you can copy those at the end of the deployment if it's really required, although I don't believe it is).

I know it's not exactly what you were expecting, but it's the best I can do without actually doing it myself.

[Djolas2001]

@kshegunov I have tried everything, but error repeats. I have re-installed MinGW and Qt both completely with right versions, put all correct dll. And nothing helps.

[SGaist]

Hi,

Did you use windeployqt to deploy your application ?

[hskoglund]

Hi, do you still get the same error "... ____cxa_throw_bad_array_new_length ..."?

I think perhaps you are copying the wrong Qt5Core.dll to your directory (where your image viewer.exe program is), you're sure you are copying Qt5Core.dll from C:\Qt\5.6\mingw492_32\bin and not from C:\Qt\Tools\QtCreator\bin?

[kshegunov]

@Djolas2001
I don't know what to suggest ... See @hskoglund's note and if nothing else works, walk us through the whole process - what dll you copied from what folder to which directory.

[Djolas2001]

I get same error. Folder link with dlls and error link. Also I have completely re-installed Qt, and now I have only MinGW as compiler so I can't miss.

[hskoglund]

Hi, how big (in bytes) is your Qt5Core.dll in your folder in D:
Also what date and time does it have?

[Djolas2001]

Here are all information about Qt5Core.dll. Also I have created short video, about how I move files.

[hskoglund]

Hi, very good idea with making a movie, now I think what your problem is, I mean how to solve it:

first, your Qt5Core.dll is indeed correct, the problem was Windows 10 saying (incorrectly) that the "..the procedure entry point __cxa_throw_bad...... could not be located in Qt5Core.dll"

Actually Qt5Core.dll imports this function from another dll called libstdc++-6.dll
This file is a part of the MinGW toolchain, but on your Windows PC you got multiple versions of this file, and the one in your path is older than the one in Qt 5.6.

So try also copying the libstdc++-6.dll from C:\Qt\5.6\mingw49_32\bin directory to your folder D: and then try to start your app again.

[Djolas2001]

@hskoglund Thank you very much, now it works. :)