On Sun, Jul 30, 2023 at 6:18 AM Anh Tuan Phan <tuananhlfc@xxxxxxxxx> wrote:
>
> This commit fixes a few compilation issues when building out of source
> tree. The command that I used to build samples/bpf:
>
> export KBUILD_OUTPUT=/tmp
> make V=1 M=samples/bpf
>
> The compilation failed since it tried to find the header files in the
> wrong places between output directory and source tree directory
Still doesn't apply cleanly, most likely due to commit bbaf1ff06af4
("bpf: Replace deprecated -target with --target= for Clang").
Please rebase and repost. Also add [PATCH bpf-next v4] tag.
> Signed-off-by: Anh Tuan Phan <tuananhlfc@xxxxxxxxx>
> ---
> Changes from v1:
> - Unconditionally add "-I $(objtree)/$(obj)" to _tprogc_flags and drop unnecessary part
> Reference:
> - v1: https://lore.kernel.org/all/67bec6a9-af59-d6f9-2630-17280479a1f7@xxxxxxxxx/
> - v2: https://lore.kernel.org/all/2ba1c076-f5bf-432f-50c1-72c845403167@xxxxxxxxx/
> ---
> samples/bpf/Makefile | 10 +++++-----
> samples/bpf/Makefile.target | 9 +--------
> 2 files changed, 6 insertions(+), 13 deletions(-)
>
> diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
> index 615f24ebc49c..cfc960b3713a 100644
> --- a/samples/bpf/Makefile
> +++ b/samples/bpf/Makefile
> @@ -341,10 +341,10 @@ $(obj)/hbm_edt_kern.o: $(src)/hbm.h $(src)/hbm_kern.h
> # Override includes for xdp_sample_user.o because $(srctree)/usr/include in
> # TPROGS_CFLAGS causes conflicts
> XDP_SAMPLE_CFLAGS += -Wall -O2 \
> - -I$(src)/../../tools/include \
> - -I$(src)/../../tools/include/uapi \
> + -I$(srctree)/tools/include \
> + -I$(srctree)/tools/include/uapi \
> -I$(LIBBPF_INCLUDE) \
> - -I$(src)/../../tools/testing/selftests/bpf
> + -I$(srctree)/tools/testing/selftests/bpf
>
> $(obj)/$(XDP_SAMPLE): TPROGS_CFLAGS = $(XDP_SAMPLE_CFLAGS)
> $(obj)/$(XDP_SAMPLE): $(src)/xdp_sample_user.h $(src)/xdp_sample_shared.h
> @@ -393,7 +393,7 @@ $(obj)/xdp_router_ipv4.bpf.o: $(obj)/xdp_sample.bpf.o
> $(obj)/%.bpf.o: $(src)/%.bpf.c $(obj)/vmlinux.h $(src)/xdp_sample.bpf.h $(src)/xdp_sample_shared.h
> @echo " CLANG-BPF " $@
> $(Q)$(CLANG) -g -O2 -target bpf -D__TARGET_ARCH_$(SRCARCH) \
> - -Wno-compare-distinct-pointer-types -I$(srctree)/include \
> + -Wno-compare-distinct-pointer-types -I$(obj) -I$(srctree)/include \
> -I$(srctree)/samples/bpf -I$(srctree)/tools/include \
> -I$(LIBBPF_INCLUDE) $(CLANG_SYS_INCLUDES) \
> -c $(filter %.bpf.c,$^) -o $@
> @@ -412,7 +412,7 @@ xdp_router_ipv4.skel.h-deps := xdp_router_ipv4.bpf.o xdp_sample.bpf.o
>
> LINKED_BPF_SRCS := $(patsubst %.bpf.o,%.bpf.c,$(foreach skel,$(LINKED_SKELS),$($(skel)-deps)))
>
> -BPF_SRCS_LINKED := $(notdir $(wildcard $(src)/*.bpf.c))
> +BPF_SRCS_LINKED := $(notdir $(wildcard $(srctree)/$(src)/*.bpf.c))
> BPF_OBJS_LINKED := $(patsubst %.bpf.c,$(obj)/%.bpf.o, $(BPF_SRCS_LINKED))
> BPF_SKELS_LINKED := $(addprefix $(obj)/,$(LINKED_SKELS))
>
> diff --git a/samples/bpf/Makefile.target b/samples/bpf/Makefile.target
> index 7621f55e2947..d2fab959652e 100644
> --- a/samples/bpf/Makefile.target
> +++ b/samples/bpf/Makefile.target
> @@ -38,14 +38,7 @@ tprog-cobjs := $(addprefix $(obj)/,$(tprog-cobjs))
> # Handle options to gcc. Support building with separate output directory
>
> _tprogc_flags = $(TPROGS_CFLAGS) \
> - $(TPROGCFLAGS_$(basetarget).o)
> -
> -# $(objtree)/$(obj) for including generated headers from checkin source files
> -ifeq ($(KBUILD_EXTMOD),)
> -ifdef building_out_of_srctree
> -_tprogc_flags += -I $(objtree)/$(obj)
> -endif
> -endif
> + -I $(objtree)/$(obj)
>
> tprogc_flags = -Wp,-MD,$(depfile) $(_tprogc_flags)
>
> --
> 2.34.1
>
