While testing the Arch Linux packages I’ve been running UnitySetup quite a lot.
I’ve noticed that some temporary files are being left in /tmp/.Trash-0 and at least on my system (Gnome) emptying the trash doesn’t get rid of them. So you need to delete them manually with rm -r /tmp/.Trash-0 or you end up wasting a few Gb of ram until the next reboot.
It’s using g_file_trash.
It looks like this can result in undesired behavior when /tmp is on a different volume than the “main” trash.
I see a bit of internet argument about whose fault this is and how(/whether) it should be fixed.