So, first time I tried to install Arch Linux ARM on the RasberryPi 4, and when I reached to pacman-key --init, this happened:
$this->bbcode_second_pass_code('', '
[root@alarmpi alarm]# pacman-key --init
pacman-conf: error while loading shared libraries: /usr/lib/libexpat.so.1: invalid ELF header
')
I checked the source files of https://archlinuxarm.org/packages/armv7h/expat, and the system's /usr/lib/libexpat.so.1.6.9 is different than that of the package:
$this->bbcode_second_pass_code('', '
[root@alarmpi alarm]# md5sum /usr/lib/libexpat.so.1.6.9
5ff9600840e5d5522b039616b936c89a /usr/lib/libexpat.so.1.6.9
[root@alarmpi alarm]# md5sum /home/alarm/usr/lib/libexpat.so.1.6.9
58984abbc203d8f29036a95d33ee816c /home/alarm/usr/lib/libexpat.so.1.6.9
')
In the end, I copied the library manually, and it fixed the issue. Not sure if this is a corruption issue or a legit one, so I'm opening this report.