1.0.1.1:

    mach exception handlers for x86/macos

    Added experimental support for mach exception handling under
    x86/macos. To enable this, turn on the feature
    :mach-exception-handler at build time.

  * restructure args to sb-posix:define-call so that :largefile
    becomes :options :largefile and add a new :c-name keyword arg.
  * for #+mach-exception-handler builds, make sb-posix:fork
    reestablish the mach exception handling thread after forking.
  * add doc/internals-notes/mach-exception-handler-notes.
  * memory_fault_handler no longer static for BSD.
  * added mach_error_memory_fault_handler for unexpected memory
    faults.
  * #+mach-exception-handler thread changes to allocate and deallocate
    mach ports.
  * added protect_control_stack_{return_}guard_page_thread calls that
    take a thread argument
  * sigill_handler no longer static on x86.
  * mach exception handling code in x86-darwin-os.c. See
    doc/internals-notes/mach-exception-handler-notes for details.