My Arch update broke today with the following error which was due to a missing soname entry in the older nss packages.

The error was identified and a post describing the error with a fix was posted to the ArchLinux news feed. Read Here

? sudo pacman -Syu                          
.....
.....
(201/201) checking for file conflicts                                                                  [------------------------------------------------------------] 100%
error: failed to commit transaction (conflicting files)
nss: /usr/lib/p11-kit-trust.so exists in filesystem
lib32-nss: /usr/lib32/p11-kit-trust.so exists in filesystem
Errors occurred, no packages were upgraded.
? pacman -Syu --overwrite /usr/lib\*/p11-kit-trust.so
.....
.....

? sudo pacman -Syu                                        
:: Synchronizing package databases...
 core is up to date
 extra is up to date
 community is up to date
 multilib is up to date
 endeavouros is up to date                                                   0.0   B  0.00   B/s 00:00 [c  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  ]   0%
:: Starting full system upgrade...
 there is nothing to do