[PATCH v5] firmware: Detect whether the toolchain supports pie and automatically disable the FW_PIC option

[Xiang W]

在 2021-07-11星期日的 12:16 +0800，Xiang W写道：
> The previous version opensbi enable the FW_PIC option by default, but
> not all toolchains can support pie. This makes some toolchain report
> erroes
> when compiling. This patch whill check whether the toolchain supports
> FW_PIC
> and disable FW_PIC.
> 
> Signed-off-by: Xiang W <wxjstz at 126.com>
This patch can be discarded, Jessica Clarke has implemented this
feature
> ---
>  firmware/objects.mk         | 4 ++++
>  scripts/toolchain-check-pie | 7 +++++++
>  2 files changed, 11 insertions(+)
>  create mode 100755 scripts/toolchain-check-pie
> 
> diff --git a/firmware/objects.mk b/firmware/objects.mk
> index ce91c2f..f8ee394 100644
> --- a/firmware/objects.mk
> +++ b/firmware/objects.mk
> @@ -17,6 +17,10 @@ ifndef FW_PIC
>  FW_PIC := y
>  endif
>  
> +ifeq ($(FW_PIC),y)
> +FW_PIC := $(shell scripts/toolchain-check-pie $(CC))
> +endif
> +
>  ifeq ($(FW_PIC),y)
>  firmware-genflags-y += -DFW_PIC
>  firmware-asflags-y  += -fpic
> diff --git a/scripts/toolchain-check-pie b/scripts/toolchain-check-
> pie
> new file mode 100755
> index 0000000..559dc42
> --- /dev/null
> +++ b/scripts/toolchain-check-pie
> @@ -0,0 +1,7 @@
> +#! /bin/bash
> +
> +if ${1} --version | head -n 1 | grep clang 2>&1 >/dev/null; then
> +       printf "void _start() {}" | ${1} --target=riscv64 -fuse-
> ld=lld -mno-relax -nostdlib -fPIE -Wl,-pie -xc - -o /dev/null
> 2>/dev/null && echo y || echo n
> +else
> +       printf "void _start() {}" | ${1} -nostdlib -fPIE -Wl,-pie -xc
> - -o /dev/null 2>/dev/null && echo y || echo n
> +fi