Kernel Compile Failing

[Scott Wells <scott@shadowsystems.us>]

Quick question... I'm sure it's something I've overlooked, but 
anyways... I'm trying to recompile the GENERIC kernel on 3.4.  Mainly to 
apply the arp patch, but to enable a couple of features as well.  
However, I'm getting the following errors during make depend:

...
In file included from /tmp/genassym_c.rYqzAv6338:13:
/usr/src/sys/arch/i386/compile/GENERIC/../../../../uvm/uvm_extern.h:370: 
sys/vmmeter.h: No such file or directory
/usr/src/sys/arch/i386/compile/GENERIC/../../../../uvm/uvm_extern.h:371: 
sys/queue.h: No such file or directory
/usr/src/sys/arch/i386/compile/GENERIC/../../../../uvm/uvm_extern.h:372: 
sys/tree.h: No such file or directory
In file included from /tmp/genassym_c.rYqzAv6338:13:
/usr/src/sys/arch/i386/compile/GENERIC/../../../../uvm/uvm_extern.h:374: 
sys/lock.h: No such file or directory
In file included from machine/pmap.h:43,
                 from 
/usr/src/sys/arch/i386/compile/GENERIC/../../../../uvm/uvm_pmap.h:86,
                 from 
/usr/src/sys/arch/i386/compile/GENERIC/../../../../uvm/uvm_extern.h:376,
                 from /tmp/genassym_c.rYqzAv6338:13:
machine/cpufunc.h:41: sys/cdefs.h: No such file or directory
machine/cpufunc.h:42: sys/types.h: No such file or directory
In file included from 
/usr/src/sys/arch/i386/compile/GENERIC/../../../../uvm/uvm_extern.h:377,
                 from /tmp/genassym_c.rYqzAv6338:13:
/usr/src/sys/arch/i386/compile/GENERIC/../../../../uvm/uvm_map.h:389: 
sys/time.h: No such file or directory
/usr/src/sys/arch/i386/compile/GENERIC/../../../../uvm/uvm_map.h:390: 
sys/proc.h: No such file or directory
/usr/src/sys/arch/i386/compile/GENERIC/../../../../uvm/uvm_map.h:391: 
sys/systm.h: No such file or directory
*** Error code 1

Stop in /usr/src/sys/arch/i386/compile/GENERIC (line 650 of Makefile).

However, if I add -I/usr/include to the INCLUDES line in the Makefile, 
all is good.  Did I miss something, have the config requirements changed 
since 3.2?  And is there any harm in adding in the -I/usr/include manually?

Thanks,

Scott