mergemaster internally using make [for example] vs. WITH_META_MODE?

mergemaster [as an example] has code like:

> # grep -i make /usr/sbin/mergemaster | more
. . .
> MM_MAKE="make ${ARCHSTRING} -m ${SOURCEDIR}/share/mk"
>         ${MM_MAKE} DESTDIR=${DESTDIR} distrib-dirs >/dev/null
>       ${MM_MAKE} DESTDIR=${TEMPROOT} distrib-dirs >/dev/null &&
>       ${MM_MAKE} _obj SUBDIR_OVERRIDE=etc >/dev/null &&
>       ${MM_MAKE} everything SUBDIR_OVERRIDE=etc >/dev/null &&
>       ${MM_MAKE} DESTDIR=${TEMPROOT} distribution >/dev/null;} ||
. . .

If one is using WITH_META_MODE= for buildworld, buidlkernel, installkernel, installworld what is appropriate for scripts or other uses of make for other makefile-targets?

Are there explicit mixes of using WITH_META_MODE= for some makefile targets and not using WITH_META_MODE= for other makefile targets that need to be avoided? Does one need to force some scripts to use [or not use] WITH_META_MODE= for their "internal" make usage?


===
Mark Millard
markmi at dsl-only.net