Re: [PATCH v3 bpf-next 04/14] samples: bpf: use own EXTRA_CFLAGS for clang commands

From: Andrii Nakryiko
Date: Mon Sep 16 2019 - 16:35:35 EST


On Mon, Sep 16, 2019 at 4:01 AM Ivan Khoronzhuk
<ivan.khoronzhuk@xxxxxxxxxx> wrote:
>
> It can overlap with CFLAGS used for libraries built with gcc if
> not now then in next patches. Correct it here for simplicity.
>
> Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@xxxxxxxxxx>
> ---

With GCC BPF front-end recently added, we should probably generalize
this to something like BPF_EXTRA_CFLAGS or something like that,
eventually. But for now:

Acked-by: Andrii Nakryiko <andriin@xxxxxx>

> samples/bpf/Makefile | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
> index b59e77e2250e..8ecc5d0c2d5b 100644
> --- a/samples/bpf/Makefile
> +++ b/samples/bpf/Makefile
> @@ -218,10 +218,10 @@ BTF_LLVM_PROBE := $(shell echo "int main() { return 0; }" | \
> /bin/rm -f ./llvm_btf_verify.o)
>
> ifneq ($(BTF_LLVM_PROBE),)
> - EXTRA_CFLAGS += -g
> + CLANG_EXTRA_CFLAGS += -g
> else
> ifneq ($(and $(BTF_LLC_PROBE),$(BTF_PAHOLE_PROBE),$(BTF_OBJCOPY_PROBE)),)
> - EXTRA_CFLAGS += -g
> + CLANG_EXTRA_CFLAGS += -g
> LLC_FLAGS += -mattr=dwarfris
> DWARF2BTF = y
> endif
> @@ -280,8 +280,8 @@ $(obj)/hbm_edt_kern.o: $(src)/hbm.h $(src)/hbm_kern.h
> # useless for BPF samples.
> $(obj)/%.o: $(src)/%.c
> @echo " CLANG-bpf " $@
> - $(Q)$(CLANG) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS) -I$(obj) \
> - -I$(srctree)/tools/testing/selftests/bpf/ \
> + $(Q)$(CLANG) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(CLANG_EXTRA_CFLAGS) \
> + -I$(obj) -I$(srctree)/tools/testing/selftests/bpf/ \
> -D__KERNEL__ -D__BPF_TRACING__ -Wno-unused-value -Wno-pointer-sign \
> -D__TARGET_ARCH_$(SRCARCH) -Wno-compare-distinct-pointer-types \
> -Wno-gnu-variable-sized-type-not-at-end \
> --
> 2.17.1
>