[v5,bpf-next,12/15] libbpf: add C/LDFLAGS to libbpf.so and test_libpf targets

Message ID 20191011002808.28206-13-ivan.khoronzhuk@linaro.org
State New
Headers show
Series
  • samples: bpf: improve/fix cross-compilation
Related show

Commit Message

Ivan Khoronzhuk Oct. 11, 2019, 12:28 a.m.
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: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>

---
 tools/lib/bpf/Makefile | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

-- 
2.17.1

Patch

diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile
index 46280b5ad48d..75b538577c17 100644
--- a/tools/lib/bpf/Makefile
+++ b/tools/lib/bpf/Makefile
@@ -174,8 +174,9 @@  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.$(LIBBPF_MAJOR_VERSION) \
-				    -Wl,--version-script=$(VERSION_SCRIPT) $^ -lelf -o $@
+	$(QUIET_LINK)$(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)|" \