[Boost-bugs] [Boost C++ Libraries] #4714: boost::tokenizer_detail::traits_extension does not expose correctly std::_Secure_char_traits_tag on VC9

Subject: [Boost-bugs] [Boost C++ Libraries] #4714: boost::tokenizer_detail::traits_extension does not expose correctly std::_Secure_char_traits_tag on VC9
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2010-10-05 12:35:56

#4714: boost::tokenizer_detail::traits_extension does not expose correctly
std::_Secure_char_traits_tag on VC9
--------------------------------+-------------------------------------------
 Reporter:  emilm@…             |       Owner:  jsiek    
     Type:  Bugs                |      Status:  new      
Milestone:  To Be Determined    |   Component:  tokenizer
  Version:  Boost 1.44.0        |    Severity:  Problem  
 Keywords:                      |  
--------------------------------+-------------------------------------------
 This issues warning C4996: 'std::char_traits<char>::[various] ': Function
 call with parameters that may be unsafe because VC STL relies on a tag to
 chose the safe/unsafe version of the function.
 {{{
  typedef std::basic_string<char>::traits_type Tr;
  typedef boost::tokenizer_detail::traits_extension<Tr> Traits;
  cout <<
 typeid(std::_Char_traits_category_helper<Tr,true>::_Secure_char_traits).name()
 << endl;
  cout <<
 typeid(std::_Char_traits_category_helper<Traits,true>::_Secure_char_traits).name()
 << endl;
 }}}

 prints
 {{{
  _Secure_char_traits_tag
  _Unsecure_char_traits_tag
 }}}
 because _Char_traits_category_helper is defined as
 {{{
 template <class _Traits>
 class _Char_traits_category_helper<_Traits, true>
  {
   public:
   typedef typename _Traits::_Secure_char_traits _Secure_char_traits;
  };
 }}}

 so it defers to a typedef of _Secure_char_traits inside the trait. By
 default it is defined to _Unsecure_char_traits_tag.

 This affects builds with /WX (treat warnings as errors) and generally
 causes a lot of warnings for otherwise harmless code (for example
 date_time relies on tokenizer to parse strings)

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/4714>
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