libbpf: Don't use cxx to test_libpf target

No need to use C++ for test_libbpf target when libbpf is on C and it
can be tested with C, after this change the CXXFLAGS in makefiles can
be avoided, at least in bpf samples, when sysroot is used, passing
same C/LDFLAGS as for lib.

Add "return 0" in test_libbpf to avoid warn, but also remove spaces at
start of the lines to keep same style and avoid warns while apply.

Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191011002808.28206-12-ivan.khoronzhuk@linaro.org

1 files changed, 20 insertions, 0 deletions

diff --git a/tools/lib/bpf/test_libbpf.c b/tools/lib/bpf/test_libbpf.c
new file mode 100644
index 000000000000..f0eb2727b766
--- /dev/null
+++ b/tools/lib/bpf/test_libbpf.c
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
+#include "libbpf.h"
+#include "bpf.h"
+#include "btf.h"
+
+/* do nothing, just make sure we can link successfully */
+
+int main(int argc, char *argv[])
+{
+	/* libbpf.h */
+	libbpf_set_print(NULL);
+
+	/* bpf.h */
+	bpf_prog_get_fd_by_id(0);
+
+	/* btf.h */
+	btf__new(NULL, 0);
+
+	return 0;
+}