On Thu, Feb 07, 2019 at 02:01:50PM -0800, ndesaulniers@xxxxxxxxxx wrote:
> This causes an issue when trying to build with `make LD=ld.lld` if
> ld.lld and the rest of your cross tools aren't in the same directory
> (ex. /usr/local/bin) (as is the case for Android's build system), as the
> GCC_TOOLCHAIN_DIR then gets set based on `which $(LD)` which will point
> where LLVM tools are, not GCC/binutils tools are located.
>
> Instead, select the GCC_TOOLCHAIN_DIR based on another tool provided by
> binutils for which LLVM does not provide a substitute for, such as
> elfedit.
>
> Fixes commit 785f11aa595b ("kbuild: Add better clang cross build support")
>
> Link: https://github.com/ClangBuiltLinux/linux/issues/341
> Suggested-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
> Signed-off-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Reviewed-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
Tested-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
> ---
> Makefile | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/Makefile b/Makefile
> index 3142e67d03f1..0eae4277206e 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -492,7 +492,7 @@ endif
> ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
> ifneq ($(CROSS_COMPILE),)
> CLANG_FLAGS := --target=$(notdir $(CROSS_COMPILE:%-=%))
> -GCC_TOOLCHAIN_DIR := $(dir $(shell which $(LD)))
> +GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
> CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)
> GCC_TOOLCHAIN := $(realpath $(GCC_TOOLCHAIN_DIR)/..)
> endif
> --
> 2.20.1.791.gb4d0f1c61a-goog
>
