Commit 793a349c authored by Ivan Khoronzhuk's avatar Ivan Khoronzhuk Committed by Alexei Starovoitov
Browse files

libbpf: Add C/LDFLAGS to libbpf.so and test_libpf targets 



In case of C/LDFLAGS there is no way to pass them correctly to build
command, for instance when --sysroot is used or external libraries
are used, like -lelf, wich can be absent in toolchain. This can be
used for samples/bpf cross-compiling allowing to get elf lib from
sysroot.

Signed-off-by: default avatarIvan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Acked-by: default avatarAndrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191011002808.28206-13-ivan.khoronzhuk@linaro.org
parent 5c26f9a7

tools/lib/bpf/Makefile

+4 −3
Original line number Diff line number Diff line
@@ -174,7 +174,8 @@ bpf_helper_defs.h: $(srctree)/include/uapi/linux/bpf.h 
$(OUTPUT)libbpf.so: $(OUTPUT)libbpf.so.$(LIBBPF_VERSION)



$(OUTPUT)libbpf.so.$(LIBBPF_VERSION): $(BPF_IN)

	$(QUIET_LINK)$(CC) --shared -Wl,-soname,libbpf.so.$(LIBBPF_MAJOR_VERSION) \

	$(QUIET_LINK)$(CC) $(LDFLAGS) \

		--shared -Wl,-soname,libbpf.so.$(LIBBPF_MAJOR_VERSION) \

		-Wl,--version-script=$(VERSION_SCRIPT) $^ -lelf -o $@

	@ln -sf $(@F) $(OUTPUT)libbpf.so

	@ln -sf $(@F) $(OUTPUT)libbpf.so.$(LIBBPF_MAJOR_VERSION)
@@ -183,7 +184,7 @@ $(OUTPUT)libbpf.a: $(BPF_IN) 
	$(QUIET_LINK)$(RM) $@; $(AR) rcs $@ $^



$(OUTPUT)test_libbpf: test_libbpf.c $(OUTPUT)libbpf.a

	$(QUIET_LINK)$(CC) $(INCLUDES) $^ -lelf -o $@

	$(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $(INCLUDES) $^ -lelf -o $@



$(OUTPUT)libbpf.pc:

	$(QUIET_GEN)sed -e "s|@PREFIX@|$(prefix)|" \

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