BuilderSet:+index crash (/builders)

https://launchpad.net/builders

OOPS-1888A1728
   - Expression: <PathExpr standard:u'context/build/fmt:link'>
   - Names:
      {'args': (),
       'context': <lp.code.model.sourcepackagerecipebuild.SourcePackageRecipeBuildJob object at 0x2ad97ad6f690>,
       'default': <object object at 0x2ad95ee32260>,
       'loop': {},
       'nothing': None,
       'options': {},
       'repeat': {},
       'request': <canonical.launchpad.webapp.servers.LaunchpadBrowserRequest instance URL=https://launchpad.net/builders/+index>,
       'template': <z3c.ptcompat.ViewPageTemplateFile object at 0x9dee590>,
       'view': <zope.browserpage.metaconfigure.SimpleViewClass from /srv/launchpad.net/production/launchpad-rev-12515/lib/lp/soyuz/browser/../templates/buildfarmbuildjob-current.pt object at 0x2ad97ad6fdd0>,
       'views': <zope.app.pagetemplate.viewpagetemplatefile.ViewMapper object at 0x11a92610>}
  Module zope.tales.expressions, line 217, in __call__
    return self._eval(econtext)
  Module zope.tales.expressions, line 194, in _eval
    ob = self._subexprs[-1](econtext)
  Module zope.tales.expressions, line 124, in _eval
    ob = self._traverser(ob, element, econtext)
  Module zope.pagetemplate.engine, line 66, in __call__
    request=request)
  Module zope.traversing.adapters, line 138, in traversePathElement
    return traversable.traverse(nm, further_path)
   - __traceback_info__: (<lp.code.model.sourcepackagerecipebuild.SourcePackageRecipeBuildJob object at 0x2ad97ad6f690>, 'build')
  Module zope.traversing.adapters, line 52, in traverse
    raise LocationError(subject, name)
   - __traceback_info__: (<lp.code.model.sourcepackagerecipebuild.SourcePackageRecipeBuildJob object at 0x2ad97ad6f690>, 'build', [])
LocationError: (<lp.code.model.sourcepackagerecipebuild.SourcePackageRecipeBuildJob object at 0x2ad97ad6f690>, 'build')