blob: fb5190652196d21428b9783c39d4957a53b12c95 [file] [log] [blame]
From dfd38cb29c0768692f886d3ab9158bd2b3132582 Mon Sep 17 00:00:00 2001
From: Changqing Li <changqing.li@windriver.com>
Date: Tue, 22 Nov 2022 15:20:48 +0800
Subject: [PATCH] makefile: use conditional assignment for KBUILD_OUTPUT
Refer [1],from make 4.4, all variables that are marked as export will
also be passed to the shell started by the shell function. use "=" will
make KBUILD_OUTPUT always empty for shell function, use "?=" to make
"export KBUILD_OUTPUT" in enrironment can work.
[snip of 4.4 NEWS]
* WARNING: Backward-incompatibility!
Previously makefile variables marked as export were not exported to commands
started by the $(shell ...) function. Now, all exported variables are
exported to $(shell ...).
[snip]
[1] https://git.savannah.gnu.org/cgit/make.git/tree/NEWS?h=4.4&id=ed493f6c9116cc217b99c2cfa6a95f15803235a2#n74
Upstream-Status: Submitted [linuxptp-devel@lists.sourceforge.net]
Signed-off-by: Changqing Li <changqing.li@windriver.com>
---
makefile | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/makefile b/makefile
index 529d8a0..3db60fa 100644
--- a/makefile
+++ b/makefile
@@ -15,7 +15,7 @@
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
-KBUILD_OUTPUT =
+KBUILD_OUTPUT ?=
DEBUG =
CC ?= $(CROSS_COMPILE)gcc
--
2.25.1