For a dep string like "|| ( foo bar ) gorp? ( bar baz )" with USE=gorp enabled, both foo and bar will be pulled in, and later foo will be removed by --depclean.
As a real life example, the current virtual/wine-0-r5 exhibits this behavior. RDEPEND=" staging? ( || ( app-emulation/wine-staging[staging] app-emulation/wine-any[staging] ) ) d3d9? ( || ( app-emulation/wine-d3d9[d3d9] app-emulation/wine-any[d3d9] ) ) || ( app-emulation/wine-vanilla[abi_x86_32=,abi_x86_64=] app-emulation/wine-staging[abi_x86_32=,abi_x86_64=] app-emulation/wine-d3d9[abi_x86_32=,abi_x86_64=] app-emulation/wine-any[abi_x86_32=,abi_x86_64=] ) !app-emulation/wine:0" emerging virtual/wine[staging] will pull in app-emulation/wine-staging and app-emulation/wine-vanilla where it would be satisfied with just wine-staging, virtual/wine[staging,d3d9] pulls in app-emulation/wine-{vanilla,staging,d3d9} where it would be satisfied with just wine-any.
It seems like the delayed || deps evaluation from bug 264434 should handle it, so that needs some investigation: https://gitweb.gentoo.org/proj/portage.git/commit/?id=e6a9e9692a8e98ccf45d90447ae083619b6f47f9
The code from bug 264434 doesn't handle the virtual/wine deps because there are multiple overlapping || groups.
When there are multiple overlapping || groups, we want to process the smaller groups first, so that the choices made for the smaller groups will influence the choices made for the larger groups.
Since virtuals are handled by recursive expansion (bug 141118), the delayed || evaluation implementation from bug 264434 doesn't apply.
The problem can be solved in the dep_zapdeps function by conversion to disjunctive normal form (DNF). For, example, this: || ( foo bar ) || ( bar baz ) Translates to DNF as: || ( ( foo bar ) ( foo baz ) ( bar bar ) ( bar baz ) ) And then the ( bar bar ) choice can be preferred since it is satisfied by the fewest number of packages.
Since DNF results in exponential explosion of the formula, my plan is to only use DNF for that parts of the dependencies that have overlapping atoms.
I have a working patch: https://github.com/gentoo/portage/pull/226
Patch posted for review: https://archives.gentoo.org/gentoo-portage-dev/message/305b6a9dbc72467a1757a7c108398a78
The bug has been referenced in the following commit(s): https://gitweb.gentoo.org/proj/portage.git/commit/?id=9fdaf9bdbdf500b7120aa95cb2ca421b931e6cea commit 9fdaf9bdbdf500b7120aa95cb2ca421b931e6cea Author: Zac Medico <zmedico@gentoo.org> AuthorDate: 2017-11-05 22:21:43 +0000 Commit: Zac Medico <zmedico@gentoo.org> CommitDate: 2017-11-14 03:35:19 +0000 dep_check: use DNF to optimize overlapping virtual || deps (bug 632026) Deps like these: || ( foo bar ) || ( bar baz ) Translate to disjunctive normal form (DNF): || ( ( foo bar ) ( foo baz ) ( bar bar ) ( bar baz ) ) Using DNF, if none of the packages are currently installed, then the ( bar bar ) choice will be automatically preferred since it is satisfied by the fewest number of packages. If the ( foo baz ) choice is already satisfied, then that choice will be preferred instead. Since DNF results in exponential explosion of the formula, only use DNF for the parts of the dependencies that have overlapping atoms. In order to simplify the implementation of the dnf_convert function, this patch also fixes _expand_new_virtuals to normalize results in the same way as use_reduce (with no redundant nested lists). Bug: https://bugs.gentoo.org/632026 Reviewed-by: Manuel Rüger <mrueg@gentoo.org> Reviewed-by: Alec Warner <antarus@gentoo.org> pym/portage/dep/_dnf.py | 90 +++++++++++++ pym/portage/dep/dep_check.py | 136 ++++++++++++++++++- pym/portage/tests/dep/test_dnf_convert.py | 48 +++++++ pym/portage/tests/dep/test_overlap_dnf.py | 28 ++++ .../resolver/test_virtual_minimize_children.py | 145 +++++++++++++++++++++ 5 files changed, 440 insertions(+), 7 deletions(-)}
