return True if user may need to turn shell off
    if mac OS version is 16 (sierra) or higher, may need to set shell off due
    to os's security requirements
    http://stackoverflow.com/questions/39702871/gdb-kind-of-doesnt-work-on-macos-sierra

def warn_startup_with_shell_off(platform, gdb_args):
    """return True if user may need to turn shell off
    if mac OS version is 16 (sierra) or higher, may need to set shell off due
    to os's security requirements
    http://stackoverflow.com/questions/39702871/gdb-kind-of-doesnt-work-on-macos-sierra
    """
    darwin_match = re.match("darwin-(\d+)\..*", platform)
    on_darwin = darwin_match is not None and int(darwin_match.groups()[0]) >= 16
    if on_darwin:
        shell_is_off = "startup-with-shell off" in gdb_args
        return not shell_is_off
    return False