Re: [PATCH v2 1/2] kbuild: fix CONFIG_CC_CAN_LINK(_STATIC) for cross-compilation with Clang

From: Nathan Chancellor
Date: Tue Jun 30 2020 - 17:14:12 EST


On Wed, Jul 01, 2020 at 12:06:24AM +0900, Masahiro Yamada wrote:
> scripts/cc-can-link.sh tests if the compiler can link userspace
> programs.
>
> When $(CC) is GCC, it is checked against the target architecture
> because the toolchain prefix is specified as a part of $(CC).
>
> When $(CC) is Clang, it is checked against the host architecture
> because --target option is missing.
>
> Pass $(CLANG_FLAGS) to scripts/cc-can-link.sh to evaluate the link
> capability for the target architecture.
>
> Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>

Reviewed-by: Nathan Chancellor <natechancellor@xxxxxxxxx>

> ---
>
> Changes in v2:
> - New patch
>
> init/Kconfig | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/init/Kconfig b/init/Kconfig
> index a46aa8f3174d..d0313e7725fa 100644
> --- a/init/Kconfig
> +++ b/init/Kconfig
> @@ -49,13 +49,13 @@ config CLANG_VERSION
>
> config CC_CAN_LINK
> bool
> - default $(success,$(srctree)/scripts/cc-can-link.sh $(CC) $(m64-flag)) if 64BIT
> - default $(success,$(srctree)/scripts/cc-can-link.sh $(CC) $(m32-flag))
> + default $(success,$(srctree)/scripts/cc-can-link.sh $(CC) $(CLANG_FLAGS) $(m64-flag)) if 64BIT
> + default $(success,$(srctree)/scripts/cc-can-link.sh $(CC) $(CLANG_FLAGS) $(m32-flag))
>
> config CC_CAN_LINK_STATIC
> bool
> - default $(success,$(srctree)/scripts/cc-can-link.sh $(CC) -static $(m64-flag)) if 64BIT
> - default $(success,$(srctree)/scripts/cc-can-link.sh $(CC) -static $(m32-flag))
> + default $(success,$(srctree)/scripts/cc-can-link.sh $(CC) $(CLANG_FLAGS) -static $(m64-flag)) if 64BIT
> + default $(success,$(srctree)/scripts/cc-can-link.sh $(CC) $(CLANG_FLAGS) -static $(m32-flag))
>
> config CC_HAS_ASM_GOTO
> def_bool $(success,$(srctree)/scripts/gcc-goto.sh $(CC))
> --
> 2.25.1
>