linux-kernel - [PATCH v2 6/9] LoongArch: Remove all -G0 switches from CFLAGS

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Message-Id: <20230624184055.3000636-7-kernel@xen0n.name>
Date:   Sun, 25 Jun 2023 02:40:52 +0800
From:   WANG Xuerui <kernel@...0n.name>
To:     Huacai Chen <chenhuacai@...nel.org>
Cc:     WANG Rui <wangrui@...ngson.cn>, Xi Ruoyao <xry111@...111.site>,
        loongarch@...ts.linux.dev, linux-kbuild@...r.kernel.org,
        llvm@...ts.linux.dev, linux-kernel@...r.kernel.org,
        WANG Xuerui <git@...0n.name>
Subject: [PATCH v2 6/9] LoongArch: Remove all -G0 switches from CFLAGS

From: WANG Xuerui <git@...0n.name>

In GCC, -G stands for "small data threshold", that instructs the
compiler to put data smaller than the specified threshold in a dedicated
"small data" section (called .sdata on LoongArch and several other
arches).

However, benefiting from this would require ABI cooperation, which is
not the case for LoongArch; and current GCC behave the same whether -G0
(equal to disabling this optimization) is given or not. So, remove -G0
from CFLAGS altogether for one less thing to care about. This also
benefits LLVM/Clang compatibility where the -G switch is not supported.

Signed-off-by: WANG Xuerui <git@...0n.name>
---
 arch/loongarch/Makefile      | 4 ++--
 arch/loongarch/vdso/Makefile | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/loongarch/Makefile b/arch/loongarch/Makefile
index a27e264bdaa5..366771016b99 100644
--- a/arch/loongarch/Makefile
+++ b/arch/loongarch/Makefile
@@ -46,8 +46,8 @@ ld-emul			= $(64bit-emul)
 cflags-y		+= -mabi=lp64s
 endif
 
-cflags-y			+= -G0 -pipe -msoft-float
-LDFLAGS_vmlinux			+= -G0 -static -n -nostdlib
+cflags-y			+= -pipe -msoft-float
+LDFLAGS_vmlinux			+= -static -n -nostdlib
 
 # When the assembler supports explicit relocation hint, we must use it.
 # GCC may have -mexplicit-relocs off by default if it was built with an old
diff --git a/arch/loongarch/vdso/Makefile b/arch/loongarch/vdso/Makefile
index 4c859a0e4754..ee4abcf5642e 100644
--- a/arch/loongarch/vdso/Makefile
+++ b/arch/loongarch/vdso/Makefile
@@ -25,7 +25,7 @@ endif
 cflags-vdso := $(ccflags-vdso) \
 	-isystem $(shell $(CC) -print-file-name=include) \
 	$(filter -W%,$(filter-out -Wa$(comma)%,$(KBUILD_CFLAGS))) \
-	-O2 -g -fno-strict-aliasing -fno-common -fno-builtin -G0 \
+	-O2 -g -fno-strict-aliasing -fno-common -fno-builtin \
 	-fno-stack-protector -fno-jump-tables -DDISABLE_BRANCH_PROFILING \
 	$(call cc-option, -fno-asynchronous-unwind-tables) \
 	$(call cc-option, -fno-stack-protector)
-- 
2.40.0