Does pacman -Syu do a force upgrade??
when i build a package myself through abs and i do a pacman -U , there are file conflicts. but when i let pacman -Syu do the upgrade, it goes through ok.
I think pacman -Syu should not do a forced upgrade (unless you add f of course) it can however do a forced downgrade (even without f option - search the forums for more info). You can of course do pacman -Uf to force an upgrade too.
pacman -Syu won't use the package you built yourself, unless you set up a local package repository, add the package to that and make sure that repo is before any other repo containing a package with the same name in your pacman.conf
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