Symptoms: the kernel crashes because it cannot execute the init process

If we run mkinitcpio with the bad busybox we have something like that that appears:

/usr/lib/libc.so.6: version `GLIBC_2.28' not found (required by /usr/lib/initcpio/busybox)

# mkinitcpio -p linux-libre-pae
==> Building image from preset: /etc/mkinitcpio.d/linux-libre-pae.preset: 'default'
  -> -k /boot/vmlinuz-linux-libre-pae -c /etc/mkinitcpio.conf -g /boot/initramfs-linux-libre-pae.img
==> Starting build: 4.17.11-gnu-1-pae
  -> Running build hook: [base]
/usr/lib/initcpio/busybox: /usr/lib/libc.so.6: version `GLIBC_2.28' not found (required by /usr/lib/initcpio/busybox)
  -> Running build hook: [udev]
  -> Running build hook: [autodetect]
  -> Running build hook: [modconf]
  -> Running build hook: [block]
  -> Running build hook: [encrypt]
  -> Running build hook: [lvm2]
  -> Running build hook: [filesystems]
  -> Running build hook: [keyboard]
  -> Running build hook: [fsck]
==> Generating module dependencies
==> Creating gzip-compressed initcpio image: /boot/initramfs-linux-libre-pae.img
==> Image generation successful
==> Building image from preset: /etc/mkinitcpio.d/linux-libre-pae.preset: 'fallback'
  -> -k /boot/vmlinuz-linux-libre-pae -c /etc/mkinitcpio.conf -g /boot/initramfs-linux-libre-pae-fallback.img -S autodetect
==> Starting build: 4.17.11-gnu-1-pae
  -> Running build hook: [base]
/usr/lib/initcpio/busybox: /usr/lib/libc.so.6: version `GLIBC_2.28' not found (required by /usr/lib/initcpio/busybox)
  -> Running build hook: [udev]
  -> Running build hook: [modconf]
  -> Running build hook: [block]
  -> Running build hook: [encrypt]
  -> Running build hook: [lvm2]
  -> Running build hook: [filesystems]
  -> Running build hook: [keyboard]
  -> Running build hook: [fsck]
==> Generating module dependencies
==> Creating gzip-compressed initcpio image: /boot/initramfs-linux-libre-pae-fallback.img
==> Image generation successful

If I revert to busybox 1.28.4-1.0 the mkinitcpio went fine

# pacman -U mkinitcpio-busybox-1.28.4-1.0-i686.pkg.tar.xz
loading packages...
warning: downgrading package mkinitcpio-busybox (1.29.2-1.0 => 1.28.4-1.0)
resolving dependencies...
looking for conflicting packages...

Package (1)         Old Version  New Version  Net Change

mkinitcpio-busybox  1.29.2-1.0   1.28.4-1.0     0.00 MiB

Total Installed Size:  0.44 MiB
Net Upgrade Size:      0.00 MiB

:: Proceed with installation? [Y/n] 
(1/1) checking keys in keyring                                                       [################################################] 100%
(1/1) checking package integrity                                                     [################################################] 100%
(1/1) loading package files                                                          [################################################] 100%
(1/1) checking for file conflicts                                                    [################################################] 100%
(1/1) checking available disk space                                                  [################################################] 100%
:: Processing package changes...
(1/1) downgrading mkinitcpio-busybox                                                 [################################################] 100%
:: Running post-transaction hooks...
(1/5) Updating linux-libre-lts initcpios...
==> Building image from preset: /etc/mkinitcpio.d/linux-libre-lts.preset: 'default'
  -> -k /boot/vmlinuz-linux-libre-lts -c /etc/mkinitcpio.conf -g /boot/initramfs-linux-libre-lts.img
==> Starting build: 4.14.58-gnu-1-lts
  -> Running build hook: [base]
  -> Running build hook: [udev]
  -> Running build hook: [autodetect]
  -> Running build hook: [modconf]
  -> Running build hook: [block]
  -> Running build hook: [encrypt]
  -> Running build hook: [lvm2]
  -> Running build hook: [filesystems]
  -> Running build hook: [keyboard]
  -> Running build hook: [fsck]
==> Generating module dependencies
==> Creating gzip-compressed initcpio image: /boot/initramfs-linux-libre-lts.img
==> Image generation successful
==> Building image from preset: /etc/mkinitcpio.d/linux-libre-lts.preset: 'fallback'
  -> -k /boot/vmlinuz-linux-libre-lts -c /etc/mkinitcpio.conf -g /boot/initramfs-linux-libre-lts-fallback.img -S autodetect
==> Starting build: 4.14.58-gnu-1-lts
  -> Running build hook: [base]
  -> Running build hook: [udev]
  -> Running build hook: [modconf]
  -> Running build hook: [block]
  -> Running build hook: [encrypt]
  -> Running build hook: [lvm2]
  -> Running build hook: [filesystems]
  -> Running build hook: [keyboard]
  -> Running build hook: [fsck]
==> Generating module dependencies
==> Creating gzip-compressed initcpio image: /boot/initramfs-linux-libre-lts-fallback.img
==> Image generation successful
[...]