Hello, I am using date_time library from Boost 1.36. When running this code: #include <boost/date_time/gregorian/gregorian.hpp> void RunDates() { boost::gregorian::date today(boost::gregorian::day_clock::local_day()); std::string todayString=boost::gregorian::to_simple_string(today); boost::gregorian::date todayFromString(boost::gregorian::from_simple_string(todayString)); } I get a reproducible crash when calling from_simple_string command on the last line of the function. Here is the backtrace: #0 0x961c9a12 in __gnu_debug::_Safe_iterator_base::_M_attach () #1 0x00003029 in __gnu_debug::_Safe_iterator_base::_Safe_iterator_base (this=0xbffff3ac, __seq=0x100698, __constant=false) at debug/ safe_base.h:89 #2 0x00006796 in __gnu_debug ::_Safe_iterator<std::_Rb_tree_iterator<std::pair<std::string const, unsigned short> >, __gnu_debug_def::map<std::string, unsigned short, std::less<std::string>, std::allocator<std::pair<std::string const, unsigned short> > > >::_Safe_iterator (this=0xbffff3ac, __i=@0xbffff35c, __seq=0x100680) at debug/safe_iterator.h:110 #3 0x000068a2 in __gnu_debug_def::map<std::string, unsigned short, std::less<std::string>, std::allocator<std::pair<std::string const, unsigned short> > >::find (this=0x100680, __x=@0xbffff4a4) at debug/ map.h:220 #4 0x00006f11 in boost::date_time::month_str_to_ushort<boost::gregorian::greg_month> (s=@0xbffff4a4) at date_parsing.hpp:68 #5 0x000071cb in boost::date_time::parse_date<boost::gregorian::date> (s=@0xbffff51c, order_spec=0) at date_parsing.hpp:142 #6 0x00007445 in boost::gregorian::from_simple_string (s=@0xbffff51c) at parsers.hpp:35 #7 0x00001f85 in RunDates () at /dates.cpp:18 #8 0x00001e18 in main (argc=1, argv=0xbffff568) at /main.cpp:8 The code was compiled on OSX, gcc version 4.0.1 (Apple Inc. build 5490) with Debug flags, I am linking against dynamic data_time library. Is this a known issue in 1.36 that was fixed in 1.38? going through the list of fixes did not uncover it. The same example compiled with release flags works without problems. I am not certain if this means that I am missing some defines or that release compile misses errors that debug catches. Any help with this is really appreciated! Thank you, Alex