On Wed, Jan 29, 2020 at 6:10 PM Yulia Kartseva <hex@xxxxxx> wrote:
>
> From: Julia Kartseva <hex@xxxxxx>
>
> Fix undefined reference linker errors when building runqslower with
> gcc 7.4.0 on Ubuntu 18.04.
> The issue is with misplaced -lelf, -lz options in Makefile:
> $(Q)$(CC) $(CFLAGS) -lelf -lz $^ -o $@
>
> -lelf, -lz options should follow the list of target dependencies:
> $(Q)$(CC) $(CFLAGS) $^ -lelf -lz -o $@
> or after substitution
> cc -g -Wall runqslower.o libbpf.a -lelf -lz -o runqslower
>
> The current order of gcc params causes failure in libelf symbols resolution,
> e.g. undefined reference to `elf_memory'
> ---
Thanks for fixing!
Just for the future, there is no need to create a cover letter for a
single patch.
Please also add Fixes tag like so:
Fixes: 9c01546d26d2 ("tools/bpf: Add runqslower tool to tools/bpf")
> tools/bpf/runqslower/Makefile | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/bpf/runqslower/Makefile b/tools/bpf/runqslower/Makefile
> index 0c021352b..87eae5be9 100644
> --- a/tools/bpf/runqslower/Makefile
> +++ b/tools/bpf/runqslower/Makefile
> @@ -41,7 +41,7 @@ clean:
>
> $(OUTPUT)/runqslower: $(OUTPUT)/runqslower.o $(BPFOBJ)
> $(call msg,BINARY,$@)
> - $(Q)$(CC) $(CFLAGS) -lelf -lz $^ -o $@
> + $(Q)$(CC) $(CFLAGS) $^ -lelf -lz -o $@
>
> $(OUTPUT)/runqslower.o: runqslower.h $(OUTPUT)/runqslower.skel.h \
> $(OUTPUT)/runqslower.bpf.o
> --
> 2.17.1
>
