selftests/bpf: Bring back c++ include/link test
Commit 5c26f9a78358 ("libbpf: Don't use cxx to test_libpf target")
converted existing c++ test to c. We still want to include and
link against libbpf from c++ code, so reinstate this test back,
this time in a form of a selftest with a clear comment about
its purpose.
v2:
* -lelf -> $(LDLIBS) (Andrii Nakryiko)
Fixes: 5c26f9a78358 ("libbpf: Don't use cxx to test_libpf target")
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191202215931.248178-1-sdf@google.com
diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile
index 3d3d024..defae23 100644
--- a/tools/lib/bpf/Makefile
+++ b/tools/lib/bpf/Makefile
@@ -152,7 +152,7 @@
VERSIONED_SYM_COUNT = $(shell readelf -s --wide $(OUTPUT)libbpf.so | \
grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 | sort -u | wc -l)
-CMD_TARGETS = $(LIB_TARGET) $(PC_FILE) $(OUTPUT)test_libbpf
+CMD_TARGETS = $(LIB_TARGET) $(PC_FILE)
all: fixdep
$(Q)$(MAKE) all_cmd
@@ -196,9 +196,6 @@
$(OUTPUT)libbpf.a: $(BPF_IN_STATIC)
$(QUIET_LINK)$(RM) $@; $(AR) rcs $@ $^
-$(OUTPUT)test_libbpf: test_libbpf.c $(OUTPUT)libbpf.a
- $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $(INCLUDES) $^ -lelf -o $@
-
$(OUTPUT)libbpf.pc:
$(QUIET_GEN)sed -e "s|@PREFIX@|$(prefix)|" \
-e "s|@LIBDIR@|$(libdir_SQ)|" \
