well, today i (partially) realized why my basic drivers don’t work: the preinstalled packages amdgpu and amdgpu-dkms seem to not work due to amdgpu-dkms being unconfigured. tried configuring it and got the same error. around about there my system stopped using even the iGPU and i had to uninstall some other drivers (thanks @lena@gregtech.eu )
@sudoleah @myersguy this will refresh db without updating system and install package. If new package depends on newer libraries than other installed packages, it will break dependencies for installed packages. That might be easily solved with local solib dependency tracking (like gentoo preserved-libs database), but arch does not have it.