[Boost-bugs] [Boost C++ Libraries] #11701: Regression in boost::intrusive::set::equal_range

Subject: [Boost-bugs] [Boost C++ Libraries] #11701: Regression in boost::intrusive::set::equal_range
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2015-10-01 06:55:02

#11701: Regression in boost::intrusive::set::equal_range
------------------------------+------------------------
 Reporter:  nyh@…             |      Owner:  igaztanaga
     Type:  Bugs              |     Status:  new
Milestone:  To Be Determined  |  Component:  intrusive
  Version:  Boost 1.57.0      |   Severity:  Regression
 Keywords:                    |
------------------------------+------------------------
 This bug was discovered by Daniel Peebles in https://github.com/cloudius-

 systems/osv/issues/635

 '''equal_range()''' is supposed to be a slightly more efficient way to
 obtain both lower_bound() and upper_bound(). But as this issue
 demonstrates, '''boost::intrusive::set''' :: equal_range() was correct in
 Boost 1.55 (tested on a Fedora 21 installation) but is broken in Boost
 1.57 (tested on a Fedora 22 installation).

 The attached simplified reproducer program builds a boost::intrusive::set
 of a "myrange" type - simple disjoint integer ranges, and then uses a
 separate user-defined comparator "comp" in finding the lower and upper
 bound, as well as equal_range.

 The output in Boost 1.55 is the expected output:

 {{{
 equal_range: (5, 8) - (10, 13)
 lower_bound: (5, 8)
 upper_bound: (10, 13)
 }}}


 Indeed, "(5,8)" is the first item to match, and "(10,13)" is the one past
 the last.

 But, the output in Boost 1.57 is different:
 {{{
 equal_range: (5, 8) - (8, 10)
 lower_bound: (5, 8)
 upper_bound: (10, 13)
 }}}

 Note how equal_range() is now incorrect ("(8,10)" still does not compare
 less according to "comp"), and moreover, different than what upper_bound()
 returns (which is the correct response).

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/11701>
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