Hi, Warning: noob inside. I am new to boost, and quite a bit rusty with C+ +, having spent the past few years with other languages. Nonetheless. I downloaded, built and installed Boost 1.40 just fine on Mac OS X 10.6 (Snow Leopard). I set up a XCode 3.2 project to compile and run the demo.cpp program delivered with the Serialization library. It crashes deep inside this line: restore_schedule(new_schedule, filename.c_str()); GDB gives the following error message: malloc: *** error for object 0x1000581a0: pointer being freed was not allocated The stack crawl shows: #0 0x7fff81202ff6 in __kill #1 0x7fff812a4072 in abort #2 0x7fff811bb095 in free #3 0x7fff836031e8 in std::string::reserve #4 0x7fff836032fe in std::string::append #5 0x10028ccac in boost ::archive::text_iarchive_impl<boost::archive::text_iarchive>::load at text_iarchive_impl.ipp:55 #6 0x100024a5e in boost ::archive::load_access::load_primitive<boost::archive::text_iarchive, std::string> at iserializer.hpp:109 #7 0x100024a83 in boost ::archive ::detail::load_non_pointer_type<boost::archive::text_iarchive, std::string>::load_primitive::invoke at iserializer.hpp:332 #8 0x100024aa8 in boost ::archive ::detail::load_non_pointer_type<boost::archive::text_iarchive, std::string>::invoke at iserializer.hpp:417 #9 0x100024acd in boost::archive::load<boost::archive::text_iarchive, std::string> at iserializer.hpp:542 #10 0x100024afe in boost ::archive ::detail ::common_iarchive <boost::archive::text_iarchive>::load_override<std::string> at common_iarchive.hpp:61 #11 0x100024b2b in boost ::archive ::basic_text_iarchive <boost::archive::text_iarchive>::load_override<std::string> at basic_text_iarchive.hpp:62 #12 0x100024b59 in boost ::archive ::text_iarchive_impl <boost::archive::text_iarchive>::load_override<std::string> at text_iarchive.hpp:66 #13 0x100024b8c in boost ::archive ::detail ::interface_iarchive <boost::archive::text_iarchive>::operator>><std::string> at interface_iarchive.hpp:61 #14 0x100024bc3 in boost ::archive ::detail ::interface_iarchive <boost::archive::text_iarchive>::operator&<std::string> at interface_iarchive.hpp:68 #15 0x100026688 in bus_stop_corner::serialize<boost::archive::text_iarchive> at main.cpp: 123 #16 0x1000266c3 in boost::serialization::access::serialize<boost::archive::text_iarchive, bus_stop_corner> at access.hpp:109 and so on... The last frame for which I have source code is #5. There the crashes occurs in the following routine: template<class Archive> BOOST_ARCHIVE_DECL(void) text_iarchive_impl<Archive>::load(std::string &s) { std::size_t size; * this->This() >> size; // skip separating space is.get(); // borland de-allocator fixup #if BOOST_WORKAROUND(_RWSTD_VER, BOOST_TESTED_AT(20101)) if(NULL != s.data()) #endif s.resize(size); // <============== crash here if(0 < size) is.read(&(*s.begin()), size); } In that frame, s is the empty string (its internal buffer points to a 0 byte), and size is 11. Suspecting a bug in OS X std::string class, I checked that the following program works fine: int main() { std::string s; std::size_t size = 11; std::cout << s << std::endl; s.resize(size); std::cout << s << std::endl; } So I tried to follow the stack up tracking the string object to see where and how it was created. I lost track of it in frame #15 on the following line: ar & street1 & street2; Note that this is back to the sample code. I decided to split that line into two lines, and surely now the crashes occurs there: ar & street1; I'm going to go on tracing through that, but maybe this rings a bell with someone, that would save me time... I can post more info if needed. Best regards and thanks, Jean-Denis