ifdefs in syscalls.master

hello.

i'm new to NetBSD, and am taking a look at the sources, with particular 
interest in syscalls.

i found the file syscalls.master.  it has a number of ifdefs, such as:
#ifdef COMPAT_43
#if defined(KTRACE) || !defined(_KERNEL)
#if defined(NFS) || defined(NFSSERVER) || !defined(_KERNEL)
..
how do i find out what the settings are for a "standard" build?  i am in 
particular interested in the settings for an ARM build.

thanks!

  - sam -