diff --git a/Makefile b/Makefile
index e5cfe7b3fb9e..603124a03ae0 100644
--- a/Makefile
+++ b/Makefile
@@ -127,7 +127,7 @@ TGTS=	all all-man buildenv buildenvvars buildkernel buildworld \
 	installworld kernel-toolchain libraries lint maninstall \
 	obj objlink rerelease showconfig tags toolchain update \
 	_worldtmp _legacy _bootstrap-tools _cleanobj _obj \
-	_build-tools _compiler-metadata _cross-tools _includes _libraries \
+	_build-tools _build-metadata _cross-tools _includes _libraries \
 	build32 distribute32 install32 buildsoft distributesoft installsoft \
 	builddtb xdev xdev-build xdev-install \
 	xdev-links native-xtools stageworld stagekernel stage-packages \
diff --git a/Makefile.inc1 b/Makefile.inc1
index 33648befb6bb..56ef0929e2d6 100644
--- a/Makefile.inc1
+++ b/Makefile.inc1
@@ -643,6 +643,49 @@ LIBCOMPAT= SOFT
 .include "Makefile.libcompat"
 .endif
 
+# META_MODE normally ignores host file changes since every build updates
+# timestamps (see NO_META_IGNORE_HOST in sys.mk).  There are known times
+# when the ABI breaks though that we want to force rebuilding WORLDTMP
+# to get updated host tools.
+.if ${MK_META_MODE} == "yes" && defined(NO_CLEAN) && \
+    !defined(NO_META_IGNORE_HOST) && !defined(NO_META_IGNORE_HOST_HEADERS)
+
+.if !defined(OBJDIR_HOST_OSRELDATE)
+.if exists(${OBJTREE}${.CURDIR}/host-osreldate.h)
+OBJDIR_HOST_OSRELDATE!=	\
+    awk '/^\#define[[:space:]]*__FreeBSD_version/ { print $$3 }' \
+    ${OBJTREE}${.CURDIR}/host-osreldate.h
+.else
+OBJDIR_HOST_OSRELDATE=	0
+.endif
+.export OBJDIR_HOST_OSRELDATE
+.endif
+
+# Note that this logic is the opposite of normal BOOTSTRAP handling.  We want
+# to compare the WORLDTMP's OSRELDATE to the host's OSRELDATE.  If the WORLDTMP
+# is older than the ABI-breakage OSRELDATE of the HOST then we rebuild.
+.for _ver in ${META_MODE_BAD_ABI_VERS}
+.if ${OSRELDATE} >= ${_ver} && ${OBJDIR_HOST_OSRELDATE} < ${_ver}
+_meta_mode_need_rebuild=	${_ver}
+.endif
+.endfor
+.if defined(_meta_mode_need_rebuild)
+.info META_MODE: Rebuilding host tools due to ABI breakage in __FreeBSD_version ${_meta_mode_need_rebuild}.
+NO_META_IGNORE_HOST_HEADERS=	1
+.export NO_META_IGNORE_HOST_HEADERS
+.endif
+.endif
+# This is only used for META_MODE+filemon to track what the oldest
+# __FreeBSD_version is in WORLDTMP.  This purposely does NOT have
+# a make dependency on /usr/include/osreldate.h as the file should
+# only be copied when it is missing or meta mode determines it has changed.
+# Since host files are normally ignored without NO_META_IGNORE_HOST
+# the file will never be updated unless that flag is specified.  This
+# allows tracking the oldest osreldate to force rebuilds via
+# META_MODE_BADABI_REVS above.
+host-osreldate.h: # DO NOT ADD /usr/include/osreldate.h here
+	@cp -f /usr/include/osreldate.h ${.TARGET}
+
 WMAKE=		${WMAKEENV} ${MAKE} ${WORLD_FLAGS} -f Makefile.inc1 DESTDIR=${WORLDTMP}
 
 IMAKEENV=	${CROSSENV}
@@ -820,12 +863,13 @@ _cross-tools:
 	@rm -f ${.OBJDIR}/compiler-metadata.mk
 	${_+_}cd ${.CURDIR}; ${XMAKE} cross-tools
 	${_+_}cd ${.CURDIR}; ${XMAKE} kernel-tools
-_compiler-metadata:
+_build-metadata:
 	@echo
 	@echo "--------------------------------------------------------------"
-	@echo ">>> stage 3.1: recording compiler metadata"
+	@echo ">>> stage 3.1: recording build metadata"
 	@echo "--------------------------------------------------------------"
 	${_+_}cd ${.CURDIR}; ${WMAKE} compiler-metadata.mk
+	${_+_}cd ${.CURDIR}; ${WMAKE} host-osreldate.h
 _includes:
 	@echo
 	@echo "--------------------------------------------------------------"
@@ -864,7 +908,7 @@ WMAKE_TGTS+=	_cleanobj
 WMAKE_TGTS+=	_obj
 .endif
 WMAKE_TGTS+=	_build-tools _cross-tools
-WMAKE_TGTS+=	_compiler-metadata
+WMAKE_TGTS+=	_build-metadata
 WMAKE_TGTS+=	_includes
 .endif
 .if !defined(NO_LIBS)
diff --git a/share/mk/sys.mk b/share/mk/sys.mk
index 202b60a263e7..c2811cd2115b 100644
--- a/share/mk/sys.mk
+++ b/share/mk/sys.mk
@@ -78,6 +78,7 @@ META_MODE?= normal
 # this should not be a real problem for incremental builds.
 # XXX: This relies on the existing host tools retaining ABI compatibility
 # through upgrades since they won't be rebuilt on header/library changes.
+# This is mitigated by Makefile.inc1 for known-ABI-breaking revisions.
 # Note that these are prefix matching, so /lib matches /libexec.
 .MAKE.META.IGNORE_PATHS+= \
 	${__MAKE_SHELL} \