id,summary,reporter,owner,description,type,status,milestone,component,version,severity,resolution,keywords,cc
12913,Undefined behaviour in serialization library,John Maddock,Robert Ramey,"Hi Robert, 

while testing multiprecision with clang's sanitizers I found some undefined behaviour in the serialization lib.  The issue can be seen by running serialization's own tests with undefined-behaviour sanitizer turned on - in fact nearly all the tests fail, but most of the failures look like issues with the tests rather than the library.  However building test_binary_xml_archive with clang++ -fsanitize=address -fsanitize=undefined -fno-sanitize-recover=undefined results in:

{{{
../../../boost/archive/detail/interface_oarchive.hpp:47:16: runtime error: downcast of address 0x7ffd0a934990 which does not point to an object of type 'boost::archive::xml_oarchive'
0x7ffd0a934990: note: object is of type 'boost::archive::xml_oarchive_impl<boost::archive::xml_oarchive>'
 fd 7f 00 00  78 ae d3 9c d6 7f 00 00  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  00 00 00 00
              ^~~~~~~~~~~~~~~~~~~~~~~
              vptr for 'boost::archive::xml_oarchive_impl<boost::archive::xml_oarchive>'
SUMMARY: AddressSanitizer: undefined-behavior ../../../boost/archive/detail/interface_oarchive.hpp:47:16 in 

}}}

Which looks like a genuine issue to me.
",Bugs,assigned,To Be Determined,serialization,Boost Development Trunk,Problem,,,