Re: [PATCH v4 1/4] powerpc/kbuild: set default generic machine type for 32-bit compile
From: Masahiro Yamada <hidden>
Date: 2018-05-29 13:41:06
Also in:
linux-kbuild
2018-05-16 23:14 GMT+09:00 Nicholas Piggin [off-list ref]:
Some 64-bit toolchains uses the wrong ISA variant for compiling 32-bit kernels, even with -m32. Debian's powerpc64le is one such case, and that is because it is built with --with-cpu=power8. So when cross compiling a 32-bit kernel with a 64-bit toolchain, set -mcpu=powerpc initially, which is the generic 32-bit powerpc machine type and scheduling model. CPU and platform code can override this with subsequent -mcpu flags if necessary. This is not done for 32-bit toolchains otherwise it would override their defaults, which are presumably set appropriately for the environment (moreso than a 64-bit cross compiler). This fixes a lot of build failures due to incompatible assembly when compiling 32-bit kernel with th Debian powerpc64le 64-bit toolchain. Cc: Segher Boessenkool <redacted> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> ---
Can you please remove the noise changes? 1/4 adds some blank lines, then 2/4 removes them.
quoted hunk ↗ jump to hunk
arch/powerpc/Makefile | 11 +++++++++++ 1 file changed, 11 insertions(+)diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile index 95813df90801..15ca4bafad82 100644 --- a/arch/powerpc/Makefile +++ b/arch/powerpc/Makefile@@ -24,9 +24,20 @@ ifeq ($(HAS_BIARCH),y) ifeq ($(CROSS32_COMPILE),) CROSS32CC := $(CC) -m32 KBUILD_ARFLAGS += --target=elf32-powerpc +
This blank line will be removed by the next patch.
+ifdef CONFIG_PPC32 +# These options will be overridden by any -mcpu option that the CPU +# or platform code sets later on the command line, but they are needed +# to set a sane 32-bit cpu target for the 64-bit cross compiler which +# may default to the wrong ISA. +KBUILD_CFLAGS += -mcpu=powerpc +KBUILD_AFLAGS += -mcpu=powerpc +endif +
This blank line will be removed by the next patch.
endif endif +
This blank line will be removed by the next patch.
export CROSS32CC CROSS32AR ifeq ($(CROSS_COMPILE),) -- 2.17.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
-- Best Regards Masahiro Yamada