dnl Available from the GNU Autoconf Macro Archive at:dnl http://www.gnu.org/software/ac-archive/htmldoc/ac_cxx_have_sstream.htmldnlAC_DEFUN([AC_CXX_HAVE_SSTREAM],[AC_CACHE_CHECK(whether the compiler has stringstream,ac_cv_cxx_have_sstream,[AC_REQUIRE([AC_CXX_NAMESPACES]) AC_LANG_SAVE AC_LANG_CPLUSPLUS AC_TRY_COMPILE([#include <sstream>#ifdef HAVE_NAMESPACESusing namespace std;#endif],[stringstream message; message << "Hello"; return 0;], ac_cv_cxx_have_sstream=yes, ac_cv_cxx_have_sstream=no) AC_LANG_RESTORE])if test "$ac_cv_cxx_have_sstream" = yes; then  AC_DEFINE(HAVE_SSTREAM,,[define if the compiler has stringstream])fi])