id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
3486	local_time::posix_time_zone_base::calc_zone Misuses String Iterator	Rob Stewart <robert.stewart@…>	az_sw_dude	"calc_zone() starts like this:
    void calc_zone(const string_type& obj){
      const char_type empty_string[2] = {'\0'};
      stringstream_type ss(empty_string);
      typename string_type::const_iterator sit = obj.begin();
      string_type l_std_zone_abbrev, l_dst_zone_abbrev;

      // get 'std' name/abbrev
      while(std::isalpha(*sit)){
        ss << *sit++;
      }

Notice that sit is never compared against obj.end().  This code apparently assumes that some non-alpha character will appear, if only a null terminator.  However, a checked STL flags *sit, in the conditional, as an error when trying to dereference the end iterator.

The particular example I encountered in which it failed was when obj was a std::string, of length 9, containing ""Australia"".  There is no non-alpha character before advancing the iterator to the end, so operator *() fails with: ""string iterator not dereferencable"" in MSVC 8 (DevStudio 2005).

I suggest changing the loop to the following:

      typename string_type::const_iterator it(obj.begin());
      typename string_type::const_iterator end(obj.end());
      // get 'std' name/abbrev
      while (it != send && std::isalpha(*it))
      {
        ss << *it++;
      }

(You can reuse end in the rest of the function, while you're at it!)"	Bugs	closed	Boost 1.41.0	date_time	Boost 1.34.0	Showstopper	fixed	calc_zone iterator