Earlier today the release team tagged PBR 2.0.0. The reason for the major
version bump is because warnerrors has been removed in favor of
warning-is-error from sphinx >= 1.5.0.
It seems that several projects outside both inside and outside OpenStack have
capped pbr <2.0.0 so we can't actually use this release yet. The requirements
team will work with all projects to remove the cap of pbr in those projects.
The good news is that projects using upper-constraints.txt are insulated from
this and shouldn't be affected. However upper-constraints.txt isn't being used
by all projects and those projects will start seeing
ContextualVersionConflicts: (pbr 2.0.0 in gate logs. It's recommended that
those projects add a local ban for pbr and associate it with:
Then once the situation is resolved we can unwind and remove the temporary caps.
 There is at least 1 corner case where the coverage job installed directly
from a git URL and therefore that wasn't protected.
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