Re: [PATCH 2/2] bpftool: Allow add linker flags via EXTRA_LDFLAGS variable

From: Song Liu
Date: Mon Oct 08 2018 - 17:03:01 EST


On Mon, Oct 8, 2018 at 1:23 AM Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
>
> Adding EXTRA_LDFLAGS allowing user to specify extra flags
> for LD_FLAGS variable. Also adding LDFLAGS to build command
> line.
>
> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Acked-by: Song Liu <songliubraving@xxxxxx>

> ---
> tools/bpf/bpftool/Makefile | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile
> index 5bfa07e3f2f7..dac7eff4c7e5 100644
> --- a/tools/bpf/bpftool/Makefile
> +++ b/tools/bpf/bpftool/Makefile
> @@ -49,6 +49,9 @@ CFLAGS += -DBPFTOOL_VERSION='"$(BPFTOOL_VERSION)"'
> ifneq ($(EXTRA_CFLAGS),)
> CFLAGS += $(EXTRA_CFLAGS)
> endif
> +ifneq ($(EXTRA_LDFLAGS),)
> +LDFLAGS += $(EXTRA_LDFLAGS)
> +endif
>
> LIBS = -lelf -lbfd -lopcodes $(LIBBPF)
>
> @@ -94,7 +97,7 @@ $(OUTPUT)disasm.o: $(srctree)/kernel/bpf/disasm.c
> $(QUIET_CC)$(COMPILE.c) -MMD -o $@ $<
>
> $(OUTPUT)bpftool: $(OBJS) $(LIBBPF)
> - $(QUIET_LINK)$(CC) $(CFLAGS) -o $@ $^ $(LIBS)
> + $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $^ $(LIBS)
>
> $(OUTPUT)%.o: %.c
> $(QUIET_CC)$(COMPILE.c) -MMD -o $@ $<
> --
> 2.17.2
>