Re: [PATCH v3] arm64: vdso32: drop -no-integrated-as flag

[Stephen Boyd]

Quoting Nick Desaulniers (2021-04-20 10:44:25)
> Clang can assemble these files just fine; this is a relic from the top
> level Makefile conditionally adding this. We no longer need --prefix,
> --gcc-toolchain, or -Qunused-arguments flags either with this change, so
> remove those too.
> 
> To test building:
> $ ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- \
>   CROSS_COMPILE_COMPAT=arm-linux-gnueabi- make LLVM=1 LLVM_IAS=1 \
>   defconfig arch/arm64/kernel/vdso32/
> 
> Suggested-by: Nathan Chancellor 
> Signed-off-by: Nick Desaulniers 
> Reviewed-by: Nathan Chancellor 
> Reviewed-by: Vincenzo Frascino 
> ---

It boots for me and compat vDSO seems to work properly per
tools/testing/selftests/vDSO/, userspace programs aren't crashing right
and left, must be good:

Tested-by: Stephen Boyd 

[PATCH v3] arm64: vdso32: drop -no-integrated-as flag

[Nick Desaulniers]

Clang can assemble these files just fine; this is a relic from the top
level Makefile conditionally adding this. We no longer need --prefix,
--gcc-toolchain, or -Qunused-arguments flags either with this change, so
remove those too.

To test building:
$ ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- \
  CROSS_COMPILE_COMPAT=arm-linux-gnueabi- make LLVM=1 LLVM_IAS=1 \
  defconfig arch/arm64/kernel/vdso32/

Suggested-by: Nathan Chancellor 
Signed-off-by: Nick Desaulniers 
Reviewed-by: Nathan Chancellor 
Reviewed-by: Vincenzo Frascino 
---
Changes V2 -> V3:
* Pick up reviewed by tags.

Changes V1 -> V2:
* Remove --prefix, --gcc-toolchain, COMPAT_GCC_TOOLCHAIN, and
  COMPAT_GCC_TOOLCHAIN_DIR as per Nathan.
* Credit Nathan with Suggested-by tag.
* Remove -Qunused-arguments.
* Update commit message.

 arch/arm64/kernel/vdso32/Makefile | 8 
 1 file changed, 8 deletions(-)

diff --git a/arch/arm64/kernel/vdso32/Makefile 
b/arch/arm64/kernel/vdso32/Makefile
index 789ad420f16b..3dba0c4f8f42 100644
--- a/arch/arm64/kernel/vdso32/Makefile
+++ b/arch/arm64/kernel/vdso32/Makefile
@@ -10,15 +10,7 @@ include $(srctree)/lib/vdso/Makefile
 
 # Same as cc-*option, but using CC_COMPAT instead of CC
 ifeq ($(CONFIG_CC_IS_CLANG), y)
-COMPAT_GCC_TOOLCHAIN_DIR := $(dir $(shell which 
$(CROSS_COMPILE_COMPAT)elfedit))
-COMPAT_GCC_TOOLCHAIN := $(realpath $(COMPAT_GCC_TOOLCHAIN_DIR)/..)
-
 CC_COMPAT_CLANG_FLAGS := --target=$(notdir $(CROSS_COMPILE_COMPAT:%-=%))
-CC_COMPAT_CLANG_FLAGS += --prefix=$(COMPAT_GCC_TOOLCHAIN_DIR)$(notdir 
$(CROSS_COMPILE_COMPAT))
-CC_COMPAT_CLANG_FLAGS += -no-integrated-as -Qunused-arguments
-ifneq ($(COMPAT_GCC_TOOLCHAIN),)
-CC_COMPAT_CLANG_FLAGS += --gcc-toolchain=$(COMPAT_GCC_TOOLCHAIN)
-endif
 
 CC_COMPAT ?= $(CC)
 CC_COMPAT += $(CC_COMPAT_CLANG_FLAGS)
-- 
2.31.1.368.gbe11c130af-goog