[Build with Boost shared memory support; for large scale authoritative DNS servers]),
[use_shared_memory=$withval])
if test X$use_shared_memory = Xyes -a "$BOOST_MAPPED_FILE_WOULDFAIL" = "yes"; then
if test X$use_shared_memory = Xyes -a "$BOOST_MAPPED_FILE_WOULDFAIL" = "yes" -a "$want_dns" = "yes"; then
AC_MSG_ERROR([Boost shared memory does not compile on this system. If you don't need it (most normal users won't) build without it by rerunning this script with --without-shared-memory; using a different compiler or a different version of Boost may also help.])