[PATCH v3 1/2] Makefile: Fix -mno-save-restore compile warning with CLANG

[Xiang W]

在 2021-12-02星期四的 17:59 +0530，Anup Patel写道：
> The riscv target of CLANG does not support -m(no-)save-restore option
> so we get compile warnings. This patch fixes compile warning by using
> -m(no-)save-restore option only for GCC.
> 
> Signed-off-by: Anup Patel <anup.patel at wdc.com>

➜  /tmp clang -target riscv64 -mno-save-restore -O2 -S test.c
➜  /tmp clang -target riscv64 -msave-restore -O2 -S test.c 
➜  /tmp clang --version                                      
Debian clang version 11.0.1-2
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/bin
➜  /tmp lsb_release -a
No LSB modules are available.
Distributor ID:	Debian
Description:	Debian GNU/Linux 11 (bullseye)
Release:	11
Codename:	bullseye
➜  /tmp

clang supports -m(no-)save-restore option on my computer

Regards,
Xiang W
> ---
>  Makefile | 12 ++++++++----
>  1 file changed, 8 insertions(+), 4 deletions(-)
> 
> diff --git a/Makefile b/Makefile
> index 8623c1c..1e35dc0 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -275,8 +275,10 @@ GENFLAGS   +=      $(platform-genflags-y)
>  GENFLAGS       +=      $(firmware-genflags-y)
>  
>  CFLAGS         =       -g -Wall -Werror -ffreestanding -nostdlib -
> fno-stack-protector -fno-strict-aliasing -O2
> -CFLAGS         +=      -fno-omit-frame-pointer -fno-optimize-
> sibling-calls
> -CFLAGS         +=      -mno-save-restore -mstrict-align
> +CFLAGS         +=      -fno-omit-frame-pointer -fno-optimize-
> sibling-calls -mstrict-align
> +ifneq ($(CC_IS_CLANG),y)
> +CFLAGS         +=      -mno-save-restore
> +endif
>  CFLAGS         +=      -mabi=$(PLATFORM_RISCV_ABI) -
> march=$(PLATFORM_RISCV_ISA)
>  CFLAGS         +=      -mcmodel=$(PLATFORM_RISCV_CODE_MODEL)
>  CFLAGS         +=      $(RELAX_FLAG)
> @@ -290,8 +292,10 @@ CPPFLAGS   +=      $(platform-cppflags-y)
>  CPPFLAGS       +=      $(firmware-cppflags-y)
>  
>  ASFLAGS                =       -g -Wall -nostdlib
> -ASFLAGS                +=      -fno-omit-frame-pointer -fno-
> optimize-sibling-calls
> -ASFLAGS                +=      -mno-save-restore -mstrict-align
> +ASFLAGS                +=      -fno-omit-frame-pointer -fno-
> optimize-sibling-calls -mstrict-align
> +ifneq ($(CC_IS_CLANG),y)
> +ASFLAGS                +=      -mno-save-restore
> +endif
>  ASFLAGS                +=      -mabi=$(PLATFORM_RISCV_ABI) -
> march=$(PLATFORM_RISCV_ISA)
>  ASFLAGS                +=      -mcmodel=$(PLATFORM_RISCV_CODE_MODEL)
>  ASFLAGS                +=      $(RELAX_FLAG)
> -- 
> 2.25.1
> 
>