The mysterious __cxa_throw_bad_array_new_length
 

When I run my program from the command line from Kubuntu 18.04 (a clean install in a VM)
it shows what the problem is.

./ChemicalADlg
./ChemicalADlg: relocation error: ./ChemicalADlg: symbol __cxa_throw_bad_array_new_length version Qt_5 not defined in file libQt5Gui.so.5 with link time reference

Doing a websearch for __cxa_throw_bad_array_new_length seems to give random discussions about make files.
There is explanation as to what __cxa_throw_bad_array_new_length is or where it comes from, which .SO file.


I use QT Creator, which is an IDE to compile my program.
My program, ChemiADlg, is also a GUI application.
On 2 PCs (Kubuntu 18.04), where Qt Creator is installed, my EXE runs fine.
On a clean install of Kubuntu 18.04, I get __cxa_throw_bad_array_new_length.
On a clean install of OpenSuse Tumbleweed, I get __cxa_throw_bad_array_new_length.

This means that if I install QT Creator, which takes something like 3 GB, my program magically will work. I can't ask ordinary people to install it just to run a 638 kB EXE.

What magic is QT Creator doing? Where is this __cxa_throw_bad_array_new_length and do all Linux not have it?

This is my project page.
https://sourceforge.net/projects/chemicala/

~~~~vmelkon

most probably it is a Qt version mismatch

 

Sounds like QT Creator is not compiling the software correctly - I would guess a configuration issue, but perhaps a QT Creator bug.

Either way, you're probably most likely to get a solution on the Qt forums - if you do please add a reply here too.

That doesn't make sense.
I am compiling for Qt 5.9.9
while OpenSuse has Qt 5.12 or something like that.

Not really. There aren't many QT users. I have asked a couple of questions on their forum and the answers provided are pretty short.
I ended up helping other people there. There is a lack of knowledgeable people. I am wondering if I made a mistake by choosing Qt.

~~~~vmelkon

This is a "usual" error message when some program was compiled using Qt version X but was running with Qt version Y.

Or there is another way as it was explained by boughtonp

Really? I thought Qt was one of the more popular ones.

*shrug* Well in that case raising it as a bug might help: https://bugreports.qt.io/browse/QTBUG

Based on Qt's versioning scheme 5.12 should be backwards compatible with 5.9


In addition, I would download the source code and try searching for stuff like 'throw.*bad.*array' to try and figure out what's triggering it and if there's a workaround.

That still does not make sense.
On Windows, when we compile a program and if our EXE needs a certain DLL and needs a certain function from that DLL, if that DLL is missing that function, then you'll get a similar message to the above.

My Linux EXE is not making a call to cxa_throw_bad_array_new_length. That function doesn't even look like a Qt function. It does not start with q or Q.

So definitely, the problem does not come from my EXE. I did not screw around with the .SO files that comes with OpenSuse either. Also, keep in mind that the same msg is being thrown by Kubuntu 18.04. So the Qt libraries that come with these OSes are intact and perfectly the right version.

~~~~vmelkon

According to this: https://stackoverflow.com/questions/...stom-built-gcc you are getting the message because of a link error.

It would seem your comment about a clean install on the hosts where it fails might be key. If your application is using dynamic linking you will need the libraries you linked to. When you install QT Creator you are also installing a version of the QT libraries and unless you statically link to those libraries they will need to be installed on the host machine.
https://doc.qt.io/qt-5/linux-deployment.html

shared libraries may use another libraries, so that is not that trivial. Actually it is a chain of libs and it is broken, that causes the relocation error.
__cxa_throw_bad_array_new_length is defined in libstdc++.so.6, so probably your version is too old or you need to use an older Qt or your compiled with a different libstdc++ or ???

My host OS is Kubuntu 18.04 and my 2 guests OSes are Kubuntu 18.04 and openSuse Tumbleweed.
I do know that Kubuntu 18.04 has libstdc++.so.6.0.25 and the size is 1,594,864 bytes.
The Kubuntu 18.04 in my VM also has the same file and same size.

Interestingly, if I open libstdc++.so.6.0.25 with Kate, I can see the function __cxa_throw_bad_array_new_length.

So, they are the same version.

~~~~vmelkon

I already tried taking the needed .SO files and placed it along with my Linux EXE and made a .SH file and run the .SH file. The .SH file comes from https://doc.qt.io/qt-5/linux-deployment.html
That just points to another cryptic error message. Something about a missing Qt plugging, xcb.
I am not using any plugins in my program. It is a simple project.

What tools are you guys using to program? What IDE? What libraries?

~~~~vmelkon

I mostly use vim - I don't use an ide very often. Currently I'm using gtkmm for gui and the libraries depend on the project. I have used QT and it's a very good product.

To get an idea of the libraries and versions you're using in your project you can run: ldd -v <yourexecutable>

You will get a list of the libraries you are linking against and the versions. You can then check and see if they exist on the computers you are testing on. You may be surprised to see the output. Installing the QT libraries brings a host of other dependencies. You can't just count on this stuff being there. There are a variety of approaches that can be taken from distributing source code with build instructions to using a packaging system. The easiest is proably to statically link your application.


Here's the output from a QT audio application:

Isn't VIM a simple text editor that runs in the terminal?
Can I have multiple files open with it and view them side by side, hit the compile button, or hit run in DEBUGGER button and do debugging?

Without a GUI and a debugger, I don't think I would be efficient at finding problems in my app.

It is a good product, it is beautiful, and I can efficiently debug with it and end up with a EXE.


I've done that. There is only a handful of .so files.
One nasty thing about Linux seems to be that it uses links on the .SO files.
For example if my app needs libQt5Core.so.5.9.9
and Linux might come with libQt5Core.so.14.2 only and there is another file called a link file libQt5Core.so.14 and there is another file libQt5Core.so
and these 2 point to libQt5Core.so.14.2

Why is it nasty? Because if I try to copy these things from my host OS to the one running in VirtualBox, it fails. It can only copy real files. It can't copy fake files like these link files.

Not really.
This page describes on what to do
https://doc.qt.io/qt-5/linux-deployment.html

#1. The configure file does not exist in /opt/Qt
#2. It exists in /opt/Qt/5.9.9/Src
#3. I ran it. Then, you have to run ./make and that runs for +1 h and consumes a lot of HDD space and I went to bed
#4. I wake and it it has failed with some cryptic messages.


So, I installed Kubuntu 20.10 in the VM and tried my EXE and also one of my other projects.


Is that something easy to do? I guess I have to make a .DEB file.

~~~~vmelkon

ldd ChemicalADlg ?

You want to know what ldd ChemicaADlg gives?

This is for the ChemicaADlg compiled for Qt 5.9.9
This is for the ChemicaADlg compiled for Qt 5.15.2
~~~~vmelkon