Re: [Boost-bugs] [Boost C++ Libraries] #2558: Unnecessary conversion warning in lexical_cast

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #2558: Unnecessary conversion warning in lexical_cast
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2013-01-21 06:30:12

#2558: Unnecessary conversion warning in lexical_cast
--------------------------------------------------+-------------------------
  Reporter:  Yang Zhang <yanghatespam@…>          |       Owner:  nasonov     
      Type:  Bugs                                 |      Status:  reopened    
 Milestone:  Boost 1.53.0                         |   Component:  lexical_cast
   Version:  Boost Development Trunk              |    Severity:  Problem     
Resolution:                                       |    Keywords:              
--------------------------------------------------+-------------------------
Changes (by anonymous):

  * status:  closed => reopened
  * resolution:  worksforme =>
  * milestone:  Boost 1.38.0 => Boost 1.53.0

Comment:

 This above code is either broken again or still broken with g++ 4.7.
 {{{
 $ g++-fsf-4.7 -I/sw/include/ -Wconversion Foo.cpp
 In file included from Foo.cpp:1:0:
 /sw/include/boost/lexical_cast.hpp: In instantiation of 'CharT*
 boost::detail::lcast_put_unsigned(T, CharT*) [with Traits =
 std::char_traits<char>; T = unsigned int; CharT = char]':
 /sw/include/boost/lexical_cast.hpp:860:13:   required from 'bool
 boost::detail::lexical_stream_limited_src<CharT, Base,
 Traits>::operator<<(int) [with CharT = char; Base =
 boost::detail::lexical_streambuf_fake; Traits = std::char_traits<char>]'
 /sw/include/boost/lexical_cast.hpp:1151:13:   required from 'Target
 boost::detail::lexical_cast(typename
 boost::call_traits<Source>::param_type, CharT*, std::size_t) [with Target
 = std::basic_string<char>; Source = int; bool Unlimited = false; CharT =
 char; typename boost::call_traits<Source>::param_type = const int;
 std::size_t = long unsigned int]'
 /sw/include/boost/lexical_cast.hpp:1174:77:   required from 'Target
 boost::lexical_cast(const Source&) [with Target = std::basic_string<char>;
 Source = int]'
 Foo.cpp:6:25:   required from here
 /sw/include/boost/lexical_cast.hpp:522:72: warning: conversion to 'char'
 from 'int' may alter its value [-Wconversion]
 /sw/include/boost/lexical_cast.hpp:524:74: warning: conversion to 'char'
 from 'int' may alter its value [-Wconversion]
 /sw/include/boost/lexical_cast.hpp:548:25: warning: conversion to 'char'
 from 'int' may alter its value [-Wconversion]
 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/2558#comment:2>
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