[Boost-bugs] [Boost C++ Libraries] #12956: Already defined errors in VS2008 ARM because of enable_if_c

Subject: [Boost-bugs] [Boost C++ Libraries] #12956: Already defined errors in VS2008 ARM because of enable_if_c
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2017-04-07 22:01:48

#12956: Already defined errors in VS2008 ARM because of enable_if_c
------------------------------------------------+--------------------------
 Reporter:  Vyacheslav Lanovets <vyacheslav@…>  |      Owner:  johnmaddock
     Type:  Bugs                                |     Status:  new
Milestone:  To Be Determined                    |  Component:
  Version:  Boost 1.63.0                        |  multiprecision
 Keywords:  enable_if_c sfinae                  |   Severity:  Problem
------------------------------------------------+--------------------------
 Solution:Use enable_if instead of enable_if_c where possible.

 To see the problem, it's enough to include cpp_bin_float.hpp.


 Win32 compiler in VS2008 sp1 compiles it normally. But ARMV4I clarm
 compiler in the same installation with Widows Mobile 6 SDK - does not.
 While there are many Windows CE systems out there, MS stopped producing
 compilers for it long time ago. Everybody is stuck with VS2008.

 Use of "::value" as argument makes it optimistically bring the function
 into scope. And later it complaints about redefinition.


 Replacing enable_if_c with enable_if wherever possible in
 cpp_bin_float.hpp apparently forces compiler to perform substitution, and
 it fails and SFINAE works.

 (After the above is changed, clarm.exe incorrectly deduce SignType of
 eval_left_shift but it's a different investigation)

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/12956>
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