libxt-1.1.5-1 is missing from mirrors (I think all, but I trashed part of my mirrorlist, but also tried on website). Appears to be all architectures (arm, arm6, arm7 arm64--tested from website). Can download x86 version, so I think something broke between here and upstream.
[rseike@alarmpi ~]$ sudo pacman -S libxt
resolving dependencies...
looking for conflicting packages...
Packages (1) libxt-1.1.5-1
Total Download Size: 0.49 MiB
Total Installed Size: 1.98 MiB
:: Proceed with installation? [Y/n]
:: Retrieving packages...
error: failed retrieving file 'libxt-1.1.5-1-armv7h.pkg.tar.xz' from ca.us.mirror.archlinuxarm.org : Operation too slow. Less than 1 bytes/sec transferred the last 10 seconds
error: failed retrieving file 'libxt-1.1.5-1-armv7h.pkg.tar.xz' from co.us.mirror.archlinuxarm.org : The requested URL returned error: 404
error: failed retrieving file 'libxt-1.1.5-1-armv7h.pkg.tar.xz' from fl.us.mirror.archlinuxarm.org : The requested URL returned error: 404
error: failed retrieving file 'libxt-1.1.5-1-armv7h.pkg.tar.xz' from mi.us.mirror.archlinuxarm.org : The requested URL returned error: 404
error: failed retrieving file 'libxt-1.1.5-1-armv7h.pkg.tar.xz' from de.us.mirror.archlinuxarm.org : The requested URL returned error: 404
warning: failed to retrieve some files
error: failed to commit transaction (unexpected error)
Errors occurred, no packages were upgraded.