port-macppc/43011: macppc64 prebuild cleanup fails in macppc/stand/ofwboot if macppc build done before

[dennis.c.ferguson%gmail.com@localhost]

>Number:         43011
>Category:       port-macppc
>Synopsis:       macppc64 prebuild cleanup fails in macppc/stand/ofwboot if 
>macppc build done before
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    port-macppc-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Mar 19 12:05:00 +0000 2010
>Originator:     Dennis Ferguson
>Release:        very recent 5.99.24
>Organization:
>Environment:
NetBSD acer.hk.akit-ferguson.com 5.99.24 NetBSD 5.99.24 (GENERIC) #0: Sun Mar 
14 17:25:30 HKT 2010  
dennis%acer.hk.akit-ferguson.com@localhost:/usr/obj/sys/arch/amd64/compile/GENERIC
 amd64

>Description:
If you do a

    MACHINE=macppc ./build.sh distribution

and then follow it with a

    MACHINE=macppc64 ./build.sh distribution

then the second build will fail trying to clean out the
sys/arch/macppc/stand/ofwboot/obj (left over from the macppc
build) because the directory ofwboot/obj/powerpc64 doesn't
exist, e.g.

cleandir ===> sys/arch/macppc/stand/ofwboot
cleaning the kern library objects
no ARCHSUBDIR for powerpc64 nor powerpc64

*** Failed target:  .BEGIN
*** Failed command: false

It may also fail if you reverse the order of the builds, though
I haven't tried that.
>How-To-Repeat:
See above.
>Fix:
Just manually doing a (cd sys/arch/macppc/stand/ofwboot/obj; rm -rf *)
prior to building makes the build happy.  I'm embarrassed to
say I have no idea what to fix in the build makefiles to
make them do it themselves.