[PATCH 1/3] RISC-V: build: Pass `-mattr` to `lld`

From: Wende Tan <twd2.me@gmail.com>
To: palmer@dabbelt.com, paul.walmsley@sifive.com,
	aou@eecs.berkeley.edu, linux-riscv@lists.infradead.org
Cc: Wende Tan <twd2.me@gmail.com>, clang-built-linux@googlegroups.com
Subject: [PATCH 1/3] RISC-V: build: Pass `-mattr` to `lld`
Date: Mon, 19 Jul 2021 20:52:47 +0000	[thread overview]
Message-ID: <20210719205247.1023289-1-twd2.me@gmail.com> (raw)

Pass `-mattr` to `lld` so that it can generate proper machine code.
By the way, it seems that `-march` does not work well now.

Signed-off-by: Wende Tan <twd2.me@gmail.com>
---
 arch/riscv/Makefile | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile
index bc74afdbf31e..bbc186a3ab45 100644
--- a/arch/riscv/Makefile
+++ b/arch/riscv/Makefile
@@ -52,9 +52,16 @@ riscv-march-$(CONFIG_ARCH_RV32I)	:= rv32ima
 riscv-march-$(CONFIG_ARCH_RV64I)	:= rv64ima
 riscv-march-$(CONFIG_FPU)		:= $(riscv-march-y)fd
 riscv-march-$(CONFIG_RISCV_ISA_C)	:= $(riscv-march-y)c
+riscv-mattr-y				:= +m,+a
+riscv-mattr-$(CONFIG_FPU)		:= $(riscv-mattr-y),+f,+d
+riscv-mattr-$(CONFIG_RISCV_ISA_C)	:= $(riscv-mattr-y),+c
 KBUILD_CFLAGS += -march=$(subst fd,,$(riscv-march-y))
 KBUILD_AFLAGS += -march=$(riscv-march-y)
 
+ifeq ($(CONFIG_LD_IS_LLD),y)
+	KBUILD_LDFLAGS += -mllvm -mattr=$(riscv-mattr-y)
+endif
+
 KBUILD_CFLAGS += -mno-save-restore
 KBUILD_CFLAGS += -DCONFIG_PAGE_OFFSET=$(CONFIG_PAGE_OFFSET)
 
-- 
2.25.1


_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv
