configure WARNINGs or errors?

[George Shaffer]

While attempting to install NTP 4.2.0 from source on an i386 OpenBSD 3.3
system I received the following warnings.

ksh: WARNING: sys/proc.h: present but cannot be compiled
ksh: WARNING: sys/proc.h: check for missing prerequisite headers?
ksh: WARNING: sys/proc.h: proceeding with the preprocessor's result
ksh: WARNING:     ## ------------------------------------ ##
ksh: WARNING:     ## Report this to address@hidden ##
ksh: WARNING:     ## ------------------------------------ ##
ksh: WARNING: sys/sysctl.h: present but cannot be compiled
ksh: WARNING: sys/sysctl.h: check for missing prerequisite headers?
ksh: WARNING: sys/sysctl.h: proceeding with the preprocessor's result
ksh: WARNING:     ## ------------------------------------ ##
ksh: WARNING:     ## Report this to address@hidden ##
ksh: WARNING:     ## ------------------------------------ ##

Subsequently make failed and I was not able to install NTP from source. 
The OpenBSD is a minimal (no X, games, or misc) but otherwise standard
install.

I installed NTP from an OpenBSD package.

George Shaffer