+AS_CASE([$dx_cv_bison_define_cmdline], [yes],
+[AC_CACHE_CHECK([whether $BISON supports api.token.raw],
+ [dx_cv_bison_api_token_raw], [dx_cv_bison_api_token_raw=no
+cat >conftest.y <<'EOF'
+%token T_TEST
+%{
+int yylex(void) { return 0; }
+void yyerror(const char *msg) { }
+%}
+%%
+input:
+EOF
+AS_IF([$BISON --define api.token.raw conftest.y >&AS_MESSAGE_LOG_FD 2>&1],
+[AC_COMPUTE_INT([testval], [T_TEST], [#include "conftest.tab.c"
+])
+AS_IF([test "$testval" -lt 256], [dx_cv_bison_api_token_raw=yes])])])
+AS_CASE([$dx_cv_bison_api_token_raw], [yes],
+ [AS_VAR_APPEND([BISON_COMPAT], [" --define api.token.raw"])])])
+