Hello!

>   cc1: warnings being treated as errors
>   ../../../../arch/i386/i386/ibcs2_machdep.c: In function `ibcs2_sendsig':
>   ../../../../arch/i386/i386/ibcs2_machdep.c:134: warning: implicit declaration
>   of function `get_vflags'
>   *** Error code 1
> This also occured when compiling from 1.3.3 source.

If I am not wrong this is exactly what got pointed out in pr 5884.
This will be fixed in 1.3.4. You can get a patch for it at
ftp://ftp.netbsd.org/pub/NetBSD/NetBSD-1.3.3/source/patches/patch-1.3.3-i386-VM86-bug.asc

Greets
-- 
   Name  : Thorsten Frueauf            Milano@irc cri@onaliM       //
   E-Mail: s_frueau@ira.uka.de oder ukfy@rz.uni-karlsruhe.de     \X/