[PATCH v2 iproute2-next 10/11] libbpf: fix clang warning about format non-literal

[Stephen Hemminger <stephen@networkplumber.org>]

Add format attribute to the format string in print routines.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
 lib/bpf_libbpf.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/bpf_libbpf.c b/lib/bpf_libbpf.c
index 50ef16bd4612..921716aec8c6 100644
--- a/lib/bpf_libbpf.c
+++ b/lib/bpf_libbpf.c
@@ -23,12 +23,14 @@
 
 #include "bpf_util.h"
 
-static int verbose_print(enum libbpf_print_level level, const char *format, va_list args)
+static int __attribute__((format(printf, 2, 0)))
+verbose_print(enum libbpf_print_level level, const char *format, va_list args)
 {
 	return vfprintf(stderr, format, args);
 }
 
-static int silent_print(enum libbpf_print_level level, const char *format, va_list args)
+static int __attribute__((format(printf, 2, 0)))
+silent_print(enum libbpf_print_level level, const char *format, va_list args)
 {
 	if (level > LIBBPF_WARN)
 		return 0;
-- 
2.30.2