OK, I think some assumptions are wrong here. You've started the build like this:
./bootstrap --prefix /x/y --unprivileged ...
cd ../devel/rcs
export PATH=/x/y:$PATH
bmake
All that is correct, but, I'm if not mistaken, you want to use `make' instead
of `bmake'. But, that just can't be used as it is because the system make
has no idea that it has to use the pkgsrc stuff sitting in the `/x/y' prefix.
You'll have to tell system make to use the config. in `/x/y'. This worked for
me:
In `/etc/mk.conf', I added:
.ifdef BSD_PKG_MK # begin pkgsrc settings
.include "/x/y/etc/mk.conf"
.endif # end pkgsrc settings
This made make(1) behave like bmake(1). Make sure to set WRKOBJDIR too.
-RVP
PS. pkgsrc gurus please correct me if I'm wrong about any of this.