[PATCH bpf-next 3/3] libbpf: BTF is required when externs are present

[Andrii Nakryiko <andriin@xxxxxx>]

BTF is required to get type information about extern variables.

Signed-off-by: Andrii Nakryiko <andriin@xxxxxx>
---
 tools/lib/bpf/libbpf.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index f90db2b18e4b..e1d91c64e093 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -1887,7 +1887,8 @@ static void bpf_object__sanitize_btf_ext(struct bpf_object *obj)
 
 static bool bpf_object__is_btf_mandatory(const struct bpf_object *obj)
 {
-	return obj->efile.btf_maps_shndx >= 0;
+	return obj->efile.btf_maps_shndx >= 0 ||
+	       obj->nr_extern > 0;
 }
 
 static int bpf_object__init_btf(struct bpf_object *obj,
-- 
2.17.1