"emerge -auv world --deep" is failing on my tree for the following reason: x11-themes/gnome-themes-2.10-0 requires x11-themes/gtk-engines-2.6.2 x11-themes/gtk-engines-2.6.2 is blocked by <=x11-themes/gnome-themes-2.8.2 currently installed is x11-themes/gnome-themes-2.8.2 The problem is resolved by explicitly unmerging gnome-themes before merging the new versions. Which means there is no _fundamental_ reason why the new versions can't be installed. The bug I'm reporting here is that emerge dependency resolution fails to recognise that merging _two_ new packages, while unmerging the old ones (it's an "emerge --update", so it will do that), is actually ok. It's caused by a kind of circular dependency: in this instance, roughly speaking, gnome-themes-2.10.0 wants gtk-engines-2.6.2, and gtk-engines-2.6.2 wants gnome-themes-2.10.0. They must be updated at the same time, for the system to continue functioning properly, and the dependency resolution doesn't seem to allow that. (This is also a case for queuing up the binary installing into "/" step so that both compiled trees for mutually dependent packages are committed to "/" simultaneously. But that's a rather fancy wishful idea). Reproducible: Always Steps to Reproduce: 1. emerge gnome-themes -auv [or what I originally was using, emerge world --deep -auv] 2. Watch it fail due to blocking conflict. 3. emerge --unmerge gnome-themes 4. Note that I already did emerge --unmerge gtk-engines before taking notes for this bug report, i.e. before the results reported from step 1. 4. emerge gnome-themes -auv => Success! Actual Results: # emerge -auv gnome-themes --oneshot These are the packages that I would merge, in order: Calculating dependencies ...done! [blocks B ] <=x11-themes/gnome-themes-2.8.2 (is blocking x11-themes/gtk-engines-2.6.2) [ebuild N ] x11-themes/gtk-engines-2.6.2 433 kB [ebuild U ] x11-themes/gnome-themes-2.10.0 [2.8.2] -accessibility -debug 2,509 kB Total size of downloads: 2,942 kB !!! Error: The above package list contains packages which cannot be installed !!! on the same system. # emerge --unmerge gnome-themes [... unmerges fine... btw, I've also unmerged gtk-engines earlier while wondering how to resolve this problem...] # emerge -auv gnome-themes --oneshot These are the packages that I would merge, in order: Calculating dependencies ...done! [ebuild N ] x11-themes/gtk-engines-2.6.2 433 kB [ebuild N ] x11-themes/gnome-themes-2.10.0 -accessibility -debug 2,509 kB Total size of downloads: 2,942 kB Do you want me to merge these packages? [Yes/No] [merge proceeds succesfully...] Expected Results: Successful update of gnome-themes and gtk-engines, with no manual intervention (the explicit unmerge of gnome-themes) required.
*** This bug has been marked as a duplicate of 79606 ***
