Re: [PATCH bpf-next 3/6] tools/libbpf: Enable cross-building with clang

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Mon, Nov 22, 2021 at 11:24 AM Jean-Philippe Brucker
<jean-philippe@xxxxxxxxxx> wrote:
>
> Cross-building using clang requires passing the "-target" flag rather
> than using the CROSS_COMPILE prefix. Makefile.include transforms
> CROSS_COMPILE into CLANG_CROSS_FLAGS. Add them to the CFLAGS.
>
> Signed-off-by: Jean-Philippe Brucker <jean-philippe@xxxxxxxxxx>
> ---
>  tools/lib/bpf/Makefile | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile
> index 5f7086fae31c..fe9201862aed 100644
> --- a/tools/lib/bpf/Makefile
> +++ b/tools/lib/bpf/Makefile
> @@ -90,6 +90,7 @@ override CFLAGS += -Werror -Wall
>  override CFLAGS += $(INCLUDES)
>  override CFLAGS += -fvisibility=hidden
>  override CFLAGS += -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64
> +override CFLAGS += $(CLANG_CROSS_FLAGS)
>
>  # flags specific for shared library
>  SHLIB_FLAGS := -DSHARED -fPIC
> @@ -162,7 +163,7 @@ $(BPF_HELPER_DEFS): $(srctree)/tools/include/uapi/linux/bpf.h
>  $(OUTPUT)libbpf.so: $(OUTPUT)libbpf.so.$(LIBBPF_VERSION)
>
>  $(OUTPUT)libbpf.so.$(LIBBPF_VERSION): $(BPF_IN_SHARED) $(VERSION_SCRIPT)
> -       $(QUIET_LINK)$(CC) $(LDFLAGS) \
> +       $(QUIET_LINK)$(CC) $(CLANG_CROSS_FLAGS) $(LDFLAGS) \

I haven't checked, but what would happen if we just use $(CFLAGS)
here? Would it still work?

>                 --shared -Wl,-soname,libbpf.so.$(LIBBPF_MAJOR_VERSION) \
>                 -Wl,--version-script=$(VERSION_SCRIPT) $< -lelf -lz -o $@
>         @ln -sf $(@F) $(OUTPUT)libbpf.so
> --
> 2.33.1
>



[Index of Archives]     [Linux Samsung SoC]     [Linux Rockchip SoC]     [Linux Actions SoC]     [Linux for Synopsys ARC Processors]     [Linux NFS]     [Linux NILFS]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]


  Powered by Linux