commit: 024e2a5779e92fffbd0a0d30c8cff725c4552626 Author: Zac Medico <zmedico <AT> gentoo <DOT> org> AuthorDate: Mon Aug 3 06:17:26 2015 +0000 Commit: Zac Medico <zmedico <AT> gentoo <DOT> org> CommitDate: Mon Aug 3 18:35:04 2015 +0000 URL: https://gitweb.gentoo.org/proj/portage.git/commit/?id=024e2a57
circular_dependency_handler: limit USE combination search (bug 555698) Limit the number of USE combinations searched to 1024 = 2 ** 10, where 10 is a constant named MAX_AFFECTING_USE, in order to avoid consuming unreasonable amounts of time. First, discard irrelevent flags that are not enabled. Since extract_affecting_use doesn't distinguish between positive and negative effects (flag? vs. !flag?), assume a positive relationship. If there are still too many combinations,then don't bother to explore any of them. X-Gentoo-Bug: 555698 X-Gentoo-Bug-url: https://bugs.gentoo.org/show_bug.cgi?id=555698 Acked-by: Brian Dolbec <dolsen <AT> gentoo.org> pym/_emerge/resolver/circular_dependency.py | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) diff --git a/pym/_emerge/resolver/circular_dependency.py b/pym/_emerge/resolver/circular_dependency.py index b710671..5c11956 100644 --- a/pym/_emerge/resolver/circular_dependency.py +++ b/pym/_emerge/resolver/circular_dependency.py @@ -14,7 +14,9 @@ from _emerge.DepPrioritySatisfiedRange import DepPrioritySatisfiedRange from _emerge.Package import Package class circular_dependency_handler(object): - + + MAX_AFFECTING_USE = 10 + def __init__(self, depgraph, graph): self.depgraph = depgraph self.graph = graph @@ -156,7 +158,7 @@ class circular_dependency_handler(object): total_flags = set() total_flags.update(affecting_use, required_use_flags) total_flags.difference_update(untouchable_flags) - if len(total_flags) <= 10: + if len(total_flags) <= self.MAX_AFFECTING_USE: affecting_use = total_flags affecting_use = tuple(affecting_use) @@ -164,6 +166,21 @@ class circular_dependency_handler(object): if not affecting_use: continue + if len(affecting_use) > self.MAX_AFFECTING_USE: + # Limit the number of combinations explored (bug #555698). + # First, discard irrelevent flags that are not enabled. + # Since extract_affecting_use doesn't distinguish between + # positive and negative effects (flag? vs. !flag?), assume + # a positive relationship. + current_use = self.depgraph._pkg_use_enabled(parent) + affecting_use = tuple(flag for flag in affecting_use + if flag in current_use) + + if len(affecting_use) > self.MAX_AFFECTING_USE: + # There are too many USE combinations to explore in + # a reasonable amount of time. + continue + #We iterate over all possible settings of these use flags and gather #a set of possible changes #TODO: Use the information encoded in REQUIRED_USE
