[SOLVED] The mysterious __cxa_throw_bad_array_new_length

vmelkon · 01-02-2021, 04:22 PM

Quote:

Originally Posted by NevemTeve

ToDo's

1. find this libQt5Gui.so.5

2. check is it exports this symbol:

Code:

nm --with-symbol-versions -D libQt5Gui.so.5 |
grep __cxa_throw_bad_array_new_length

3. if it does export it, find out if it accidental or intentional. (This will be the hard part.)

I ran that on a PC where Qt Creator is installed. I have installed it with the sudo command. Perhaps I should have installed it as a regular user?

Anyway, this is interesting

Code:

nm --with-symbol-versions -D /opt/Qt/5.9.9/gcc_64/lib/libQt5Gui.so.5 | grep __cxa_throw_bad_array_new_length
Gives:
00000000004aa800 T __cxa_throw_bad_array_new_length@@Qt_5@@Qt_5

nm --with-symbol-versions -D /opt/Qt/5.12.2/gcc_64/lib/libQt5Gui.so.5 | grep __cxa_throw_bad_array_new_length
Gives:
000000000050f0d0 T __cxa_throw_bad_array_new_length@@Qt_5@@Qt_5

nm --with-symbol-versions -D /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5 | grep __cxa_throw_bad_array_new_length
Gives:
nothing

Code:

nm --with-symbol-versions -D /opt/Qt/5.9.9/gcc_64/lib/libQt5Widgets.so.5 | grep __cxa_throw_bad_array_new_length
Gives:
nothing

nm --with-symbol-versions -D /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 | grep __cxa_throw_bad_array_new_length
Gives:
nothing

Code:

nm --with-symbol-versions -D /opt/Qt/5.9.9/gcc_64/lib/libQt5Core.so.5 | grep __cxa_throw_bad_array_new_length
Gives:
                 U __cxa_throw_bad_array_new_length


nm --with-symbol-versions -D /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 | grep __cxa_throw_bad_array_new_length
Gives:
                 U __cxa_throw_bad_array_new_length@@CXXABI_1.3.8@CXXABI_1.3.8

/opt/Qt/5.9.9/gcc_64/lib
is a folder created by the Qt Creator installer. There are a lot of .SO files there and other file types.
libQt5Gui.so.5.9.9
^^^^^My Project uses 5.9.9

There is also Qt 5.12.2 that I can use but the same problem is present
/opt/Qt/5.12.2/gcc_64/lib/
has the file
libQt5Gui.so.5.12.2

Code:

nm --with-symbol-versions -D /opt/Qt/5.12.2/gcc_64/lib/libQt5Gui.so.5 | grep __cxa_throw_bad_array_new_length
Gives:
000000000050f0d0 T __cxa_throw_bad_array_new_length@@Qt_5@@Qt_5

/usr/lib/x86_64-linux-gnu/
has
libQt5Gui.so.5.14.2

~~~~vmelkon

vmelkon · 01-03-2021, 12:32 AM

Quote:

Originally Posted by NevemTeve

ToDo's

1. find this libQt5Gui.so.5

2. check is it exports this symbol:

Code:

nm --with-symbol-versions -D libQt5Gui.so.5 |
grep __cxa_throw_bad_array_new_length

3. if it does export it, find out if it accidental or intentional. (This will be the hard part.)

I asked about it at
https://forum.qt.io/topic/122290/dif...i-so-5-linux/2

So, for me, the problem is solved. I just replaced the offending file in /opt/Qt and recompiled my 3 projects.
Thanks NevemTeve and everyone who tried to help.

~~~~vmelkon

NevemTeve · 01-03-2021, 06:34 AM

I would try this to remove the problematic symbol:

Code:

objcopy --strip-symbol __cxa_throw_bad_array_new_length libQt5Gui.so.5

Then rebuild your executable.

vmelkon · 01-03-2021, 10:39 AM

Quote:

Originally Posted by NevemTeve

I would try this to remove the problematic symbol:

Code:

objcopy --strip-symbol __cxa_throw_bad_array_new_length libQt5Gui.so.5

Then rebuild your executable.

I copied the offending file (libQt5Gui.so.5.9.9) to my home folder
/home/jake

Code:

nm --with-symbol-versions -D libQt5Gui.so.5.9.9 | grep __cxa_throw_bad_array_new_length
Gives:
00000000004aa800 T __cxa_throw_bad_array_new_length@@Qt_5

objcopy --strip-symbol __cxa_throw_bad_array_new_length libQt5Gui.so.5.9.9

nm --with-symbol-versions -D libQt5Gui.so.5.9.9 | grep __cxa_throw_bad_array_new_length
Gives:
00000000004aa800 T __cxa_throw_bad_array_new_length@@Qt_5

I also tried

Code:

nm --with-symbol-versions -D /home/jake/libQt5Gui.so.5.9.9 | grep __cxa_throw_bad_array_new_length
Gives:
00000000004aa800 T __cxa_throw_bad_array_new_length@@Qt_5

objcopy --strip-symbol __cxa_throw_bad_array_new_length /home/jake/libQt5Gui.so.5.9.9

nm --with-symbol-versions -D /home/jake/libQt5Gui.so.5.9.9 | grep __cxa_throw_bad_array_new_length
Gives:
00000000004aa800 T __cxa_throw_bad_array_new_length@@Qt_5

so it looks like it was not able to remove it.
However, that is a neat idea.

~~~~vmelkon

NevemTeve · 01-03-2021, 11:55 AM

I've Just checked, It doesn't affect dynamic symbols.

pan64 · 01-03-2021, 12:28 PM

from my point of view: if the given shared object needs that [any] symbol you need to "serve"it, so you need to use it with the required and compatible libraries.
Actually the available libstdc++ and libQt5Gui.so.5 are not compatible with each other. Or if you build that so: the development/build environment and the runtime environment are different, incompatible.

vmelkon · 01-03-2021, 06:58 PM

Quote:

Originally Posted by pan64

from my point of view: if the given shared object needs that [any] symbol you need to "serve"it, so you need to use it with the required and compatible libraries.
Actually the available libstdc++ and libQt5Gui.so.5 are not compatible with each other. Or if you build that so: the development/build environment and the runtime environment are different, incompatible.

I didn't build that SO file. It is just the version that QT Creator installs.
Perhaps there is a disagreement going on with boys over at Qt and the boys on the OS side of things.
I'm going to assume that the way done by the OS boys is the right way.

Quote:

Actually the available libstdc++ and libQt5Gui.so.5 are not compatible with each other

Which libQt5Gui.so.5? The one from the OS or the one from Qt Creator?

~~~~vmelkon