[xen master] build: Allow setting KBUILD_DEFCONFIG in the environment

[patchbot@xxxxxxx]

commit adac94da8bbd8affe04dcaefac8d0872025f9e5f
Author:     Michal Orzel <michal.orzel@xxxxxxx>
AuthorDate: Wed Oct 25 10:28:34 2023 +0200
Commit:     Stefano Stabellini <stefano.stabellini@xxxxxxx>
CommitDate: Tue Nov 7 12:38:50 2023 -0800

    build: Allow setting KBUILD_DEFCONFIG in the environment
    
    At the moment, in order to use a different defconfig target than default,
    one needs to specify KBUILD_DEFCONFIG=<target> on the command line.
    Switch to weak assignment, so that it can be also obtained from
    environment similar to other KCONFIG/KBUILD variables.
    
    This change will activate the use of KBUILD_DEFCONFIG variable in CI
    build jobs that so far would have had no effect if they didn't match the
    default anyway.
    
    Note, that we will deviate from Linux in this regard.
    
    Signed-off-by: Michal Orzel <michal.orzel@xxxxxxx>
    [stefano: adjust commit message]
    Signed-off-by: Stefano Stabellini <stefano.stabellini@xxxxxxx>
    Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
---
 xen/Makefile | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/xen/Makefile b/xen/Makefile
index b923235c53..7b869f4b30 100644
--- a/xen/Makefile
+++ b/xen/Makefile
@@ -256,7 +256,8 @@ export YACC = $(if $(BISON),$(BISON),bison)
 export LEX = $(if $(FLEX),$(FLEX),flex)
 
 # Default file for 'make defconfig'.
-export KBUILD_DEFCONFIG := $(ARCH)_defconfig
+# May be overruled on the command line or set in the environment.
+export KBUILD_DEFCONFIG ?= $(ARCH)_defconfig
 
 # Copy CFLAGS generated by "Config.mk" so they can be reused later without
 # reparsing Config.mk by e.g. arch/x86/boot/.
--
generated by git-patchbot for /home/xen/git/xen.git#master