[Boost-bugs] [Boost C++ Libraries] #12027: is_base_of<B, D> should work ehen B is incomplete

Subject: [Boost-bugs] [Boost C++ Libraries] #12027: is_base_of<B, D> should work ehen B is incomplete
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2016-02-27 11:37:28

#12027: is_base_of<B, D> should work ehen B is incomplete
------------------------------+-------------------------
 Reporter:  akrzemi1          |      Owner:  johnmaddock
     Type:  Bugs              |     Status:  new
Milestone:  To Be Determined  |  Component:  type_traits
  Version:  Boost 1.61.0      |   Severity:  Problem
 Keywords:                    |
------------------------------+-------------------------
 The Standard ([meta.rel]) requires that in is_base_of<B, D> D must be a
 complete type, but it does not require the same of B. This makes sense,
 because if we compare a complete type D and an incomplete type B, the
 former is surely not derived from the latter.

 In contrast, boost::is_base_of imposes an additional constraint that B
 must also be complete:

 http://www.boost.org/doc/libs/1_60_0/libs/type_traits/doc/html/boost_typetraits/reference/is_base_of.html


 Can you remove this extra constraint? It appears to be spoiling one
 Boost.Optional tests:

 http://www.boost.org/development/tests/master/developer/output/oracle-

 sparc-S2-12-5-cpp11-boost-bin-v2-libs-optional-test-optional_test-test-
 sun-12-5_cpp11-release-threading-multi.html

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/12027>
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