[PATCH 4.18 53/53] ARC: build: Dont set CROSS_COMPILE in archs Makefile

From: Greg Kroah-Hartman
Date: Thu Oct 18 2018 - 13:58:56 EST

4.18-stable review patch. If anyone has any objections, please let me know.


From: Alexey Brodkin <abrodkin@xxxxxxxxxxxx>

commit 40660f1fcee8d524a60b5101538e42b1f39f106d upstream.

There's not much sense in doing that because if user or
his build-system didn't set CROSS_COMPILE we still may
very well make incorrect guess.

But as it turned out setting CROSS_COMPILE is not as harmless
as one may think: with recent changes that implemented automatic
discovery of __host__ gcc features unconditional setup of
CROSS_COMPILE leads to failures on execution of "make xxx_defconfig"
with absent cross-compiler, for more info see [1].

Set CROSS_COMPILE as well gets in the way if we want only to build
.dtb's (again with absent cross-compiler which is not really needed
for building .dtb's), see [2].

Note, we had to change LIBGCC assignment type from ":=" to "="
so that is is resolved on its usage, otherwise if it is resolved
at declaration time with missing CROSS_COMPILE we're getting this
error message from host GCC:

| gcc: error: unrecognized command line option -mmedium-calls
| gcc: error: unrecognized command line option -mno-sdata

[1] http://lists.infradead.org/pipermail/linux-snps-arc/2018-September/004308.html
[2] http://lists.infradead.org/pipermail/linux-snps-arc/2018-September/004320.html

Signed-off-by: Alexey Brodkin <abrodkin@xxxxxxxxxxxx>
Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
Cc: Rob Herring <robh@xxxxxxxxxx>
Signed-off-by: Vineet Gupta <vgupta@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

arch/arc/Makefile | 10 +---------
1 file changed, 1 insertion(+), 9 deletions(-)

--- a/arch/arc/Makefile
+++ b/arch/arc/Makefile
@@ -6,14 +6,6 @@
# published by the Free Software Foundation.

-ifeq ($(CROSS_COMPILE),)
-CROSS_COMPILE := arc-linux-
-CROSS_COMPILE := arceb-linux-
KBUILD_DEFCONFIG := nsim_700_defconfig

cflags-y += -fno-common -pipe -fno-builtin -mmedium-calls -D__linux__
@@ -73,7 +65,7 @@ ldflags-$(CONFIG_CPU_BIG_ENDIAN) += -EB
# --build-id w/o "-marclinux". Default arc-elf32-ld is OK
ldflags-$(upto_gcc44) += -marclinux

-LIBGCC := $(shell $(CC) $(cflags-y) --print-libgcc-file-name)
+LIBGCC = $(shell $(CC) $(cflags-y) --print-libgcc-file-name)

# Modules with short calls might break for calls into builtin-kernel
KBUILD_CFLAGS_MODULE += -mlong-calls -mno-millicode