Re: [Boost-bugs] [Boost C++ Libraries] #11998: Static const variables cannot be logged

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #11998: Static const variables cannot be logged
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2016-02-18 10:02:04

#11998: Static const variables cannot be logged
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  Reporter:  Hendrik Schall <torres@…>  |      Owner:  andysem
      Type:  Bugs                       |     Status:  new
 Milestone:  To Be Determined           |  Component:  log
   Version:  Boost 1.60.0               |   Severity:  Problem
Resolution:                             |   Keywords:  log static const
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Comment (by andysem):

 I don't think this is a bug in the library.

 The static constant members have to be defined in some (one) translation
 unit, which gives them storage. In C++11 and later this is required if a
 reference to the variable is taken, which happens when you call the
 `operator<<`. In pre-C++11 versions of the language, IIRC, the definition
 is required unconditionally.

 The type conversion that you use as a workaround makes the `operator<<`
 bind the reference to a temporary, that's why it works. I'm not sure how
 it works differently in 1.59 since I don't see any changes that could lead
 to that but there were such changes since 1.58 - the `operator<<`
 overloads could have been chosen differently before, which would result in
 not taking the reference.

 However, I can see that your use case could be useful, and I'll see if I
 can support it in the future.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/11998#comment:1>
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