[PATCH 2/2] arch: use cross_compiling to check whether it is a cross build or not

[PATCH 2/2] arch: use cross_compiling to check whether it is a cross build or not

[Masahiro Yamada]

'cross_compiling' is defined by the top Makefile and available for
arch Makefiles to check whether it is a cross build or not. A good
thing is the variable name 'cross_compiling' is self-documenting.

This is a simple replacement for m68k, mips, sh, for which $(ARCH)
and $(SRCARCH) always match.

No functional change is intended for xtensa, either.

This is rather a fix for parisc because arch/parisc/Makefile defines
UTS_MATCHINE depending on CONFIG_64BIT, therefore cc-cross-prefix
is not working in Kconfig time.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---

 arch/m68k/Makefile   | 2 +-
 arch/mips/Makefile   | 2 +-
 arch/parisc/Makefile | 2 +-
 arch/sh/Makefile     | 2 +-
 arch/xtensa/Makefile | 6 +-----
 5 files changed, 5 insertions(+), 9 deletions(-)

diff --git a/arch/m68k/Makefile b/arch/m68k/Makefile
index ea14f2046fb4..82620f14124d 100644
--- a/arch/m68k/Makefile
+++ b/arch/m68k/Makefile
@@ -16,7 +16,7 @@
 
 KBUILD_DEFCONFIG := multi_defconfig
 
-ifneq ($(SUBARCH),$(ARCH))
+ifdef cross_compiling
 	ifeq ($(CROSS_COMPILE),)
 		CROSS_COMPILE := $(call cc-cross-prefix, \
 			m68k-linux-gnu- m68k-linux- m68k-unknown-linux-gnu-)
diff --git a/arch/mips/Makefile b/arch/mips/Makefile
index e71d587af49c..258234c35a09 100644
--- a/arch/mips/Makefile
+++ b/arch/mips/Makefile
@@ -50,7 +50,7 @@ tool-archpref		= $(64bit-tool-archpref)
 UTS_MACHINE		:= mips64
 endif
 
-ifneq ($(SUBARCH),$(ARCH))
+ifdef cross_compiling
   ifeq ($(CROSS_COMPILE),)
     CROSS_COMPILE := $(call cc-cross-prefix, $(tool-archpref)-linux-  $(tool-archpref)-linux-gnu-  $(tool-archpref)-unknown-linux-gnu-)
   endif
diff --git a/arch/parisc/Makefile b/arch/parisc/Makefile
index 7d9f71aa829a..aed8ea29268b 100644
--- a/arch/parisc/Makefile
+++ b/arch/parisc/Makefile
@@ -41,7 +41,7 @@ endif
 
 export LD_BFD
 
-ifneq ($(SUBARCH),$(UTS_MACHINE))
+ifdef cross_compiling
 	ifeq ($(CROSS_COMPILE),)
 		CC_SUFFIXES = linux linux-gnu unknown-linux-gnu
 		CROSS_COMPILE := $(call cc-cross-prefix, \
diff --git a/arch/sh/Makefile b/arch/sh/Makefile
index 3bcbf52fb30e..44bcb80e791a 100644
--- a/arch/sh/Makefile
+++ b/arch/sh/Makefile
@@ -9,7 +9,7 @@
 # License.  See the file "COPYING" in the main directory of this archive
 # for more details.
 #
-ifneq ($(SUBARCH),$(ARCH))
+ifdef cross_compiling
   ifeq ($(CROSS_COMPILE),)
     CROSS_COMPILE := $(call cc-cross-prefix, sh-linux- sh-linux-gnu- sh-unknown-linux-gnu-)
   endif
diff --git a/arch/xtensa/Makefile b/arch/xtensa/Makefile
index ba9fee75e675..e9c8f064c44d 100644
--- a/arch/xtensa/Makefile
+++ b/arch/xtensa/Makefile
@@ -19,12 +19,8 @@ variant-y := $(patsubst "%",%,$(CONFIG_XTENSA_VARIANT_NAME))
 VARIANT = $(variant-y)
 export VARIANT
 
-# Test for cross compiling
-
 ifneq ($(VARIANT),)
-  COMPILE_ARCH = $(shell uname -m)
-
-  ifneq ($(COMPILE_ARCH), xtensa)
+  ifdef cross_compiling
     ifndef CROSS_COMPILE
       CROSS_COMPILE = xtensa_$(VARIANT)-
     endif
-- 
2.27.0

Re: [PATCH 2/2] arch: use cross_compiling to check whether it is a cross build or not

[Geert Uytterhoeven]

Hi Yamada-san,

On Sat, May 1, 2021 at 7:26 PM Masahiro Yamada <masahiroy@kernel.org> wrote:
> 'cross_compiling' is defined by the top Makefile and available for
> arch Makefiles to check whether it is a cross build or not. A good
> thing is the variable name 'cross_compiling' is self-documenting.
>
> This is a simple replacement for m68k, mips, sh, for which $(ARCH)
> and $(SRCARCH) always match.
>
> No functional change is intended for xtensa, either.
>
> This is rather a fix for parisc because arch/parisc/Makefile defines
> UTS_MATCHINE depending on CONFIG_64BIT, therefore cc-cross-prefix
> is not working in Kconfig time.
>
> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

>  arch/m68k/Makefile   | 2 +-

Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH 2/2] arch: use cross_compiling to check whether it is a cross build or not

[Max Filippov]

On Sat, May 1, 2021 at 10:25 AM Masahiro Yamada <masahiroy@kernel.org> wrote:
>
> 'cross_compiling' is defined by the top Makefile and available for
> arch Makefiles to check whether it is a cross build or not. A good
> thing is the variable name 'cross_compiling' is self-documenting.
>
> This is a simple replacement for m68k, mips, sh, for which $(ARCH)
> and $(SRCARCH) always match.
>
> No functional change is intended for xtensa, either.
>
> This is rather a fix for parisc because arch/parisc/Makefile defines
> UTS_MATCHINE depending on CONFIG_64BIT, therefore cc-cross-prefix
> is not working in Kconfig time.
>
> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
> ---
>
>  arch/m68k/Makefile   | 2 +-
>  arch/mips/Makefile   | 2 +-
>  arch/parisc/Makefile | 2 +-
>  arch/sh/Makefile     | 2 +-
>  arch/xtensa/Makefile | 6 +-----
>  5 files changed, 5 insertions(+), 9 deletions(-)

Acked-by: Max Filippov <jcmvbkbc@gmail.com> # xtensa

-- 
Thanks.
-- Max

Re: [PATCH 2/2] arch: use cross_compiling to check whether it is a cross build or not

[Rob Landley]

On 5/1/21 12:24 PM, Masahiro Yamada wrote:
> 'cross_compiling' is defined by the top Makefile and available for
> arch Makefiles to check whether it is a cross build or not. A good
> thing is the variable name 'cross_compiling' is self-documenting.
> 
> This is a simple replacement for m68k, mips, sh, for which $(ARCH)
> and $(SRCARCH) always match.
> 
> No functional change is intended for xtensa, either.
> 
> This is rather a fix for parisc because arch/parisc/Makefile defines
> UTS_MATCHINE depending on CONFIG_64BIT, therefore cc-cross-prefix
> is not working in Kconfig time.
> 
> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Tried the patch in my sh build, the result built and booted.

Tested-by: Rob Landley <rob@landley.net>

Rob