if test "$GXX" = yes; then

        OLD_CXXFLAGS="${CXXFLAGS}"

        # -Wno-return-type-c-linkage is desired so that stable ICU API is not warned about.

        CXXFLAGS="${CXXFLAGS} -std=c++11"

        ac_ext=cpp

ac_cpp='$CXXCPP $CPPFLAGS'

ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5'

ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'

ac_compiler_gnu=$ac_cv_cxx_compiler_gnu

        cat confdefs.h - <<_ACEOF >conftest.$ac_ext

/* end confdefs.h.  */

static const char16_t test[] = u"This is a UTF16 literal string.";

int

main ()

{

  ;

  return 0;

}

_ACEOF

if ac_fn_cxx_try_compile "$LINENO"; then :

  CXX_UTF16_STRING=1

else

  CXX_UTF16_STRING=0

fi

rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext

        ac_ext=c

ac_cpp='$CPP $CPPFLAGS'

ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'

ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'

ac_compiler_gnu=$ac_cv_c_compiler_gnu

        if test "$CXX_UTF16_STRING" = 1; then

            if test "$CC_UTF16_STRING" = 1; then

                CHECK_UTF16_STRING_RESULT="available";

            else

                CHECK_UTF16_STRING_RESULT="C++ only";

            fi

        else

            CXXFLAGS="${OLD_CXXFLAGS}"

        fi

    fi