[Boost-bugs] [Boost C++ Libraries] #2045: lexical_cast<std::string> of short unsigned produces warnigns with g++ and -Wsign-promo

Subject: [Boost-bugs] [Boost C++ Libraries] #2045: lexical_cast<std::string> of short unsigned produces warnigns with g++ and -Wsign-promo
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2008-06-24 07:51:16

#2045: lexical_cast<std::string> of short unsigned produces warnigns with g++ and
-Wsign-promo
---------------------------------+------------------------------------------
 Reporter:  aeriksson_at_[hidden]  |       Owner:  nasonov     
     Type:  Bugs                 |      Status:  new         
Milestone:  Boost 1.36.0         |   Component:  lexical_cast
  Version:  Boost 1.35.0         |    Severity:  Problem     
 Keywords:                       |  
---------------------------------+------------------------------------------
 {{{
 #include <boost/lexical_cast.hpp>

 void foo() {
   short unsigned int x;
   boost::lexical_cast<std::string>(x);
 }
 }}}

 Compiled with g++ 4.2.0, boost 1.35.0, and the -Wsign-promo flag this
 produces the following warnings:

 {{{
 /opt/boost/include/boost-1_35/boost/lexical_cast.hpp: In member function
 ‘bool boost::detail::lexical_stream_limited_src<CharT, Base,
 Traits>::operator<<(short unsigned int) [with CharT = char, Base =
 boost::detail::lexical_streambuf_fake, Traits = std::char_traits<char>]’:
 /opt/boost/include/boost-1_35/boost/lexical_cast.hpp:1146:   instantiated
 from ‘Target boost::detail::lexical_cast(typename
 boost::call_traits<Source>::param_type, CharT*, size_t) [with Target =
 std::basic_string<char, std::char_traits<char>, std::allocator<char> >,
 Source = short unsigned int, bool Unlimited = false, CharT = char]’
 /opt/boost/include/boost-1_35/boost/lexical_cast.hpp:1170:   instantiated
 from ‘Target boost::lexical_cast(const Source&) [with Target =
 std::basic_string<char, std::char_traits<char>, std::allocator<char> >,
 Source = short unsigned int]’
 lexicalWarning.cpp:5:   instantiated from here
 /opt/boost/include/boost-1_35/boost/lexical_cast.hpp:910: warning: passing
 ‘short unsigned int’ chooses ‘int’ over ‘long int’
 /opt/boost/include/boost-1_35/boost/lexical_cast.hpp:910: warning:   in
 call to ‘unsigned int boost::detail::lcast_to_unsigned(int)’
 }}}

-- 
Ticket URL: <http://svn.boost.org/trac/boost/ticket/2045>
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