Provide a bit of anti-foot-shooting protection. Make sure that in the

non-cross cases without DESTDIR, that the bin/sh that we're about to
install works.  Otherwise, a 'make installworld' without having already
rebooted with a post-signal-fix kernel is a rather big disaster when
important things like /bin/sh coredump.

Makefile.inc1

@@ -356,6 +356,13 @@ installcheck:
 		false; \
 	fi
 .endif
+.if ${TARGET_ARCH} == ${MACHINE_ARCH} && \
+    (!defined(DESTDIR) || ${DESTDIR} == "" || ${DESTDIR} == "/")
+	@echo "Checking to see if your booted kernel is fresh enough.."
+	${.OBJDIR}/bin/sh/sh -c \
+	    'echo "Testing installed kernel for new sigaction(2) syscall"'
+	@echo "Seems ok.."
+.endif
 
 #
 # distributeworld