From fdbd473ce57080845c13750e72bb82fa0ca32e33 Mon Sep 17 00:00:00 2001
From: Glen Barber <gjb@FreeBSD.org>
Date: Wed, 6 Jan 2016 05:23:25 +0000
Subject: [PATCH] Add a new target to touch the ${.OBJDIR}/release file, which
 indicates the 'release' target has run (in order to prevent subsequent
 invocations that may clobber original build output).

As is, the 'release' target is a dummy target that does nothing
more than depend on subsequent targets.  Unless 'make obj' is
invoked prior to 'make release', .OBJDIR and .CURDIR will always
be '/usr/src/release' (or wherever /usr/src is located).

When 'make release' invokes 'make real-release' (and subsequent
targets), .OBJDIR is not updated, which still leads to src/ tree
pollution.

While arguably a hack, 'make release' will invoke the original
dummy targets as originally intended, but instead of touching an
empty file (or returing @true), will call a 'release-done' target
that will trigger the behavior that was intended to prevent
a subsequent invocation.

Discussed with:	hrs
MFC after:	3 days
X-MFC-With:	r293173
Sponsored by:	The FreeBSD Foundation
---
 release/Makefile | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/release/Makefile b/release/Makefile
index 07b8048de48..ba1ca80c050 100644
--- a/release/Makefile
+++ b/release/Makefile
@@ -281,7 +281,11 @@ ftp: packagesystem
 	cp *.txz MANIFEST ftp
 
 release:	real-release vm-release cloudware-release
-	touch ${.OBJDIR}/${.TARGET}
+	${MAKE} -C ${.CURDIR} ${.MAKEFLAGS} release-done
+	true
+
+release-done:
+	touch release
 
 real-release:
 	${MAKE} -C ${.CURDIR} ${.MAKEFLAGS} obj