- machine/hal_sysinfo.h sys/table.h sys/param.h sys/sysctl.h \
- sys/systemcfg.h],,, [AC_INCLUDES_DEFAULT])
+ machine/hal_sysinfo.h sys/table.h sys/param.h sys/systemcfg.h],,,
+ [AC_INCLUDES_DEFAULT])
+ dnl <sys/sysctl.h> requires <sys/param.h> on OpenBSD 4.0.
+ AC_CHECK_HEADERS([sys/sysctl.h],,,
+ [AC_INCLUDES_DEFAULT
+ #if HAVE_SYS_PARAM_H
+ # include <sys/param.h>
+ #endif
+ ])