Re: [Boost-bugs] [Boost C++ Libraries] #13315: boost 1.65.1 gcc 5.4 redefinition error in boost/type_traits/is_unsigned.hpp

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #13315: boost 1.65.1 gcc 5.4 redefinition error in boost/type_traits/is_unsigned.hpp
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2017-12-01 13:23:58

#13315: boost 1.65.1 gcc 5.4 redefinition error in
boost/type_traits/is_unsigned.hpp
-------------------------------+--------------------------
  Reporter:  wiki908@…         |      Owner:  John Maddock
      Type:  Support Requests  |     Status:  new
 Milestone:  Boost 1.65.0      |  Component:  type_traits
   Version:  Boost 1.65.0      |   Severity:  Problem
Resolution:                    |   Keywords:
-------------------------------+--------------------------

Comment (by Michel Morin):

 I think this is a compiler bug (though I don't understand what happens in
 the code).
 Here is a smaller testcase
 {{{
 #include <iostream>

 typedef unsigned long long cl_ulong __attribute__((aligned(8)));

 void f()
 {
     // unsigned long long x; // OK
     cl_ulong x; // Error
     std::cout << x;
 }

 template <class T> struct is_unsigned {};
 template <> struct is_unsigned<      unsigned long long> {};
 template <> struct is_unsigned<const unsigned long long> {};
 }}}

 G++-5 fails to compile the code on C++11, 14, 17 modes with the following
 error messages
 {{{
 Line14: error: redefinition of 'struct is_unsigned<long long unsigned
 int>'
  template <> struct is_unsigned<const unsigned long long> {};
                     ^
 Line13: error: previous definition of 'struct is_unsigned<long long
 unsigned int>'
  template <> struct is_unsigned<      unsigned long long> {};
 }}}

-- 
Ticket URL: <https://svn.boost.org/trac10/boost/ticket/13315#comment:2>
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