[Boost-bugs] [Boost C++ Libraries] #11742: lengauer_tarjan_dominator_tree: doesn't respect indexMap parameter

Subject: [Boost-bugs] [Boost C++ Libraries] #11742: lengauer_tarjan_dominator_tree: doesn't respect indexMap parameter
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2015-10-21 00:51:42

#11742: lengauer_tarjan_dominator_tree: doesn't respect indexMap parameter
---------------------------------------------+----------------------
 Reporter:  Justin Viiret <justin.viiret@…>  |      Owner:  jewillco
     Type:  Bugs                             |     Status:  new
Milestone:  To Be Determined                 |  Component:  graph
  Version:  Boost 1.59.0                     |   Severity:  Problem
 Keywords:                                   |
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 The more complex version of `lengauer_tarjan_dominator_tree`, as described
 in the BGL documentation, takes a parameter `indexMap` which is to be used
 as the index map of the graph.

 However, if you look at the code for
 `lengauer_tarjan_dominator_tree_without_dfs` (which is called by the
 `lengauer_tarjan_dominator_tree` function), the `indexMap` argument is not
 used, and instead the `dominator_visitor` just uses `get(vertex_index, g)`
 explicitly when constructing its internal property maps.

 This means that graphs that do not have a `vertex_index` property can't
 use the algorithm.

 I believe the correct fix is to pass the provided index map into the
 `dominator_visitor` constructor, and use it when constructing the other
 maps held by the visitor.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/11742>
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