fixes#7198
We recently bumped the bundled version of PyQt (5.14.2->5.15.4).
It seems the new version has a lot more dynamic dependencies.
From https://doc.qt.io/qt-5/linux-requirements.html :
> From Qt 5.15 onwards, Qt does require libxcb 1.11. Also, the -qt-xcb
> configure option got removed that was bundling some of the libs below.
We are using the prebuilt wheels for PyQt5 from PyPI. Presumably those
had previously been built using the -qt-xcb option.
Ubuntu 20.04 needs `libxcb-xinerama.so.0`
and Debian 10 needs `libxcb-util.so.1` for the Qt `xcb` plugin.
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ported from 380f04a805
see https://github.com/Electron-Cash/Electron-Cash/issues/2196
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In particular, see this comment:
>> I confirmed that both Ubuntu 20.04 and Debian 10.8 clean install have an issue with the 4.2.4 AppImage.
>
> Any idea what broke it? I assume it used to work.
Yes, it did work in 4.2.3 which used PyQt5 5.13.2. I just had a look at the xcb plugin and it definitely has less dependencies:
```
ago@ubuntu2004vm:~/src/Electron-Cash/dist$ ldd squashfs-root/usr/lib/python3.6/site-packages/PyQt5/Qt/plugins/platforms/libqxcb.so|grep xcb
libX11-xcb.so.1 => /lib/x86_64-linux-gnu/libX11-xcb.so.1 (0x00007f0ec9d07000)
libxcb.so.1 => /lib/x86_64-linux-gnu/libxcb.so.1 (0x00007f0ec9cdd000)
libxcb-xkb.so.1 => /lib/x86_64-linux-gnu/libxcb-xkb.so.1 (0x00007f0ec6ead000)
```
compared to PyQt5 5.15.2 in 4.2.4:
```
ago@ubuntu2004vm:~/src/Electron-Cash/dist$ ldd squashfs-root/usr/lib/python3.8/site-packages/PyQt5/Qt/plugins/platforms/libqxcb.so|grep xcb
libX11-xcb.so.1 => /lib/x86_64-linux-gnu/libX11-xcb.so.1 (0x00007fcb5715f000)
libxcb-icccm.so.4 => /lib/x86_64-linux-gnu/libxcb-icccm.so.4 (0x00007fcb57158000)
libxcb-image.so.0 => /lib/x86_64-linux-gnu/libxcb-image.so.0 (0x00007fcb56f51000)
libxcb-shm.so.0 => /lib/x86_64-linux-gnu/libxcb-shm.so.0 (0x00007fcb56f4c000)
libxcb-util.so.1 => /lib/x86_64-linux-gnu/libxcb-util.so.1 (0x00007fcb56d46000)
libxcb-keysyms.so.1 => /lib/x86_64-linux-gnu/libxcb-keysyms.so.1 (0x00007fcb56d41000)
libxcb-randr.so.0 => /lib/x86_64-linux-gnu/libxcb-randr.so.0 (0x00007fcb56d2e000)
libxcb-render-util.so.0 => /lib/x86_64-linux-gnu/libxcb-render-util.so.0 (0x00007fcb56d27000)
libxcb-render.so.0 => /lib/x86_64-linux-gnu/libxcb-render.so.0 (0x00007fcb56d16000)
libxcb-shape.so.0 => /lib/x86_64-linux-gnu/libxcb-shape.so.0 (0x00007fcb56d11000)
libxcb-sync.so.1 => /lib/x86_64-linux-gnu/libxcb-sync.so.1 (0x00007fcb56d07000)
libxcb-xfixes.so.0 => /lib/x86_64-linux-gnu/libxcb-xfixes.so.0 (0x00007fcb56cfd000)
libxcb-xinerama.so.0 => /lib/x86_64-linux-gnu/libxcb-xinerama.so.0 (0x00007fcb56cf8000)
libxcb-xkb.so.1 => /lib/x86_64-linux-gnu/libxcb-xkb.so.1 (0x00007fcb56cda000)
libxcb.so.1 => /lib/x86_64-linux-gnu/libxcb.so.1 (0x00007fcb56cae000)
```
Had to also bump ubuntu version 18.04->20.04,
as was getting errors running the self-compiled pyinstaller otherwise (weird...):
```
from .utils.git import get_repo_revision
ModuleNotFoundError: No module named 'PyInstaller.utils'
```
(similar to https://github.com/pyinstaller/pyinstaller/issues/4403 )
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Note re appimage: when trying to compile python 3.8.x on ubuntu 16.04, I am getting:
./Modules/posixmodule.c: In function ‘os_copy_file_range_impl’:
./Modules/posixmodule.c:10351:15: error: implicit declaration of function ‘copy_file_range’ [-Werror=implicit-function-declaration]
ret = copy_file_range(src, p_offset_src, dst, p_offset_dst, count, flags);
This is because ubuntu 16.04 has too old glibc.
This slightly increases the AppImage size but allows us to be more
compatible with older distributions.
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taken from Electron-Cash/Electron-Cash@96644acd6fd66f866a86613974bb68bb99f00d8c
Thorsten Hempel
ThomasV
SomberNight
Axel Gembe
gruve-p
Jin Eguchi