error C2668: 'abs' : ambiguous call to overloaded function

From: Black Ice (yg-boost-users_at_[hidden])
Date: 2003-01-02 21:49:44

boost version 2002-01-02
VC 7.1 Final Beta
"error C2668: 'abs' : ambiguous call to overloaded function" when compile
following code. The same code can be built successfully in vc6.
Any suggestion are appreciated.

#define DATE_TIME_INLINE
#define BOOST_DATE_TIME_POSIX_TIME_STD_CONFIG

#include <iostream>
#include <string>
using namespace std;

#include <boost/date_time/gregorian/gregorian.hpp>
#include <boost/date_time/posix_time/posix_time.hpp>

using namespace boost::gregorian;
using namespace boost::posix_time;

void testDateTime2()
{
 date d(2002, Nov, 1); //an arbitrary date
 ptime t1(d, hours(5) + nanosec(100));//date + time of day offset
 ptime t2 = t1 - minutes(4)+seconds(2);
 ptime now = second_clock::local_time(); //use the clock
 //Get the date part out of the time
 date today = now.date();
 date tommorrow = today + date_duration(1);
 ptime tommorrow_start(tommorrow); //midnight

 cout << "d is " << to_iso_extended_string(d) << endl;
 cout << "t1 is " << to_iso_extended_string(t1) << endl;
 cout << "t2 is " << to_iso_extended_string(t2) << endl;
 cout << "now is " << to_iso_extended_string(now) << endl;
 cout << "today is " << to_iso_extended_string(today) << endl;
 cout << "tommorrow is " << to_iso_extended_string(tommorrow) << endl;
 cout << "tommorrow_start is " << to_iso_extended_string(tommorrow_start) <<
endl;

 //starting at current time iterator adds by one hour
 time_iterator titr(now,hours(1));
 for (; titr < tommorrow_start; ++titr) {
  cout << to_iso_extended_string(*titr) << endl;
 }
}

--
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