#endif
#if HAVE_STDBOOL_H
# include <stdbool.h>
+#else
+# ifndef HAVE__BOOL
+# ifdef __cplusplus
+typedef bool _Bool;
+# else
+# define _Bool signed char
+# endif
+# endif
+# define bool _Bool
+# define false 0
+# define true 1
+# define __bool_true_false_are_defined 1
#endif
#if HAVE_UNISTD_H
# include <unistd.h>