problem running "make cleandir"

[Robert Huff]

	I run "make cleandir" in /usr/src as part of building world/kernel.
	On a system that gets updated every midnight, for the last few days I 
have been getting:

make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: duplicate 
script for target "all_subdir_libnv" ignored
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: using 
previous script for "all_subdir_libnv" defined here
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: duplicate 
script for target "all-man_subdir_libnv" ignored
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: using 
previous script for "all-man_subdir_libnv" defined here
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: duplicate 
script for target "checkdpadd_subdir_libnv" ignored
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: using 
previous script for "checkdpadd_subdir_libnv" defined here
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: duplicate 
script for target "clean_subdir_libnv" ignored
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: using 
previous script for "clean_subdir_libnv" defined here
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: duplicate 
script for target "cleandepend_subdir_libnv" ignored
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: using 
previous script for "cleandepend_subdir_libnv" defined here
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: duplicate 
script for target "cleandir_subdir_libnv" ignored
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: using 
previous script for "cleandir_subdir_libnv" defined here
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: duplicate 
script for target "cleanilinks_subdir_libnv" ignored
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: using 
previous script for "cleanilinks_subdir_libnv" defined here
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: duplicate 
script for target "depend_subdir_libnv" ignored
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: using 
previous script for "depend_subdir_libnv" defined here
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: duplicate 
script for target "distribute_subdir_libnv" ignored
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: using 
previous script for "distribute_subdir_libnv" defined here
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: duplicate 
script for target "lint_subdir_libnv" ignored
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: using 
previous script for "lint_subdir_libnv" defined here
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: duplicate 
script for target "maninstall_subdir_libnv" ignored
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: using 
previous script for "maninstall_subdir_libnv" defined here
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: duplicate 
script for target "manlint_subdir_libnv" ignored
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: using 
previous script for "manlint_subdir_libnv" defined here
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: duplicate 
script for target "obj_subdir_libnv" ignored
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: using 
previous script for "obj_subdir_libnv" defined here
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: duplicate 
script for target "objlink_subdir_libnv" ignored
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: using 
previous script for "objlink_subdir_libnv" defined here
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: duplicate 
script for target "realinstall_subdir_libnv" ignored
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: using 
previous script for "realinstall_subdir_libnv" defined here
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: duplicate 
script for target "regress_subdir_libnv" ignored
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: using 
previous script for "regress_subdir_libnv" defined here
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: duplicate 
script for target "tags_subdir_libnv" ignored
make[2]: "/usr/src/share/mk/bsd.subdir.mk" line 89: warning: using 
previous script for "tags_subdir_libnv" defined here
make[3]: "/usr/src/share/mk/bsd.subdir.mk" line 104: warning: duplicate 
script for target "includes" ignored
make[3]: "/usr/src/share/mk/bsd.subdir.mk" line 69: warning: using 
previous script for "includes" defined here

	World and kernel are synched at r263263.
	Is there a missing or damaged file somewhere, have I managed to mangle 
something else, or is there a more subtle problem?

	Respectfully,


				Robert Huff