Hi! When I run the following program, #include <boost/program_options.hpp> int main() { boost::program_options::positional_options_description positional; return 0; } the program aborts with the error sandbox(1791) malloc: *** error for object 0x7fff70506500: pointer being freed was not allocated *** set a breakpoint in malloc_error_break to debug My platform is Mac OS X 10.6.7. I installed Boost 1.46.1 on my own, like so: ./bootstrap --prefix=/usr/local ./bjam memory-model=64 ./bjam install The toolset bjam chose was darwin, which uses gcc-4.0 if I understood the build correctly. I also tried rebuilding boost with ./bjam memory-model=64 toolset=darwin-4.2 but the issue persisted. Any idea what causes this crash? Matan