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| author | Nick Desaulniers <ndesaulniers@google.com> | 2022-10-24 21:44:41 +0200 |
|---|---|---|
| committer | Russell King (Oracle) <rmk+kernel@armlinux.org.uk> | 2022-11-08 19:36:17 +0100 |
| commit | a2faac39866d0313f3ca59c36a9f4e077faf4f53 (patch) | |
| tree | dc61ac59188ca8484ce96c572abfbd0a574df274 /arch/arm/kernel/Makefile | |
| parent | ARM: 9262/1: remove lazy evaluation in Makefile (diff) | |
| download | linux-a2faac39866d0313f3ca59c36a9f4e077faf4f53.tar.xz linux-a2faac39866d0313f3ca59c36a9f4e077faf4f53.zip | |
ARM: 9263/1: use .arch directives instead of assembler command line flags
Similar to commit a6c30873ee4a ("ARM: 8989/1: use .fpu assembler
directives instead of assembler arguments").
GCC and GNU binutils support setting the "sub arch" via -march=,
-Wa,-march, target function attribute, and .arch assembler directive.
Clang was missing support for -Wa,-march=, but this was implemented in
clang-13.
The behavior of both GCC and Clang is to
prefer -Wa,-march= over -march= for assembler and assembler-with-cpp
sources, but Clang will warn about the -march= being unused.
clang: warning: argument unused during compilation: '-march=armv6k'
[-Wunused-command-line-argument]
Since most assembler is non-conditionally assembled with one sub arch
(modulo arch/arm/delay-loop.S which conditionally is assembled as armv4
based on CONFIG_ARCH_RPC, and arch/arm/mach-at91/pm-suspend.S which is
conditionally assembled as armv7-a based on CONFIG_CPU_V7), prefer the
.arch assembler directive.
Add a few more instances found in compile testing as found by Arnd and
Nathan.
Link: https://github.com/llvm/llvm-project/commit/1d51c699b9e2ebc5bcfdbe85c74cc871426333d4
Link: https://bugs.llvm.org/show_bug.cgi?id=48894
Link: https://github.com/ClangBuiltLinux/linux/issues/1195
Link: https://github.com/ClangBuiltLinux/linux/issues/1315
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Diffstat (limited to 'arch/arm/kernel/Makefile')
| -rw-r--r-- | arch/arm/kernel/Makefile | 2 |
1 files changed, 0 insertions, 2 deletions
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index 553866751e1a..e64ed3a82f70 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -71,7 +71,6 @@ obj-$(CONFIG_HAVE_TCM) += tcm.o obj-$(CONFIG_OF) += devtree.o obj-$(CONFIG_CRASH_DUMP) += crash_dump.o obj-$(CONFIG_SWP_EMULATE) += swp_emulate.o -CFLAGS_swp_emulate.o := -Wa,-march=armv7-a obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o obj-$(CONFIG_CPU_XSCALE) += xscale-cp0.o @@ -100,7 +99,6 @@ CFLAGS_head-inflate-data.o := $(call cc-option,-Wframe-larger-than=10240) obj-$(CONFIG_XIP_DEFLATED_DATA) += head-inflate-data.o obj-$(CONFIG_ARM_VIRT_EXT) += hyp-stub.o -AFLAGS_hyp-stub.o :=-Wa,-march=armv7-a ifeq ($(CONFIG_ARM_PSCI),y) obj-$(CONFIG_SMP) += psci_smp.o endif |