Intermittent Segmentation Faults since #239

[dougkpowers]

I'm getting some intermittent seg faults since #239. It has not been consistent so I'm struggling to pin it down.

Mac OS
Exception Type: EXC_BAD_ACCESS (SIGSEGV)
Exception Codes: KERN_INVALID_ADDRESS at 0x00007fe7bbb00000
Exception Note: EXC_CORPSE_NOTIFY

Top of Thread #0: 0 libsystem_kernel.dylib 0x00007fff20669a5e __ulock_wait + 10

Top of Thread #1: 0 libsystem_malloc.dylib 0x00007fff204c618d small_malloc_from_free_list + 344
.... WriteGeometryVisitor::operator()(boost::geometry::model::multi_polygon<boost::geometry::model::polygon<boost::geometry::model::d2::point_xy<double, boo
st::geometry::cs::cartesian>, true, true, std::__1::vector

Top of Thread #2: 0 bool boost::geometry::detail::get_turns::get_turns_in_sections

Just putting this out there to see if anyone else is experiencing this.

[kleunen]

Try this:
#245

[dougkpowers]

haven't received a segfault since pulling latest.