[PATCH 5.0 074/139] objtool: Allow AR to be overridden with HOSTAR

Greg Kroah-Hartman
2019-05-23T19:23:23Z

From: Nathan Chancellor <natechancellor@gmail.com>

commit 8ea58f1e8b11cca3087b294779bf5959bf89cc10 upstream.

Currently, this Makefile hardcodes GNU ar, meaning that if it is not
available, there is no way to supply a different one and the build will
fail.

$ make AR=llvm-ar CC=clang LD=ld.lld HOSTAR=llvm-ar HOSTCC=clang \
HOSTLD=ld.lld HOSTLDFLAGS=-fuse-ld=lld defconfig modules_prepare
...
AR /out/tools/objtool/libsubcmd.a
/bin/sh: 1: ar: not found
...

Follow the logic of HOST{CC,LD} and allow the user to specify a
different ar tool via HOSTAR (which is used elsewhere in other
tools/ Makefiles).

Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Cc: <stable@vger.kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/80822a9353926c38fd7a152991c6292491a9d0e8.1558028966.git.jpoimboe@redhat.com
Link: https://github.com/ClangBuiltLinux/linux/issues/481
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
tools/objtool/Makefile | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/tools/objtool/Makefile
+++ b/tools/objtool/Makefile
@@ -7,11 +7,12 @@ ARCH := x86
endif

# always use the host compiler
+HOSTAR ?= ar
HOSTCC ?= gcc
HOSTLD ?= ld
+AR = $(HOSTAR)
CC = $(HOSTCC)
LD = $(HOSTLD)
-AR = ar

ifeq ($(srctree),)
srctree := $(patsubst %/,%,$(dir $(CURDIR)))