1 files changed, 2 insertions, 1 deletions
diff --git a/trace.c b/trace.c
index d95341693f..3d744d1d4d 100644
--- a/trace.c
+++ b/trace.c
@@ -62,7 +62,7 @@ static int get_trace_fd(const char *key, int *need_close)
 static const char err_msg[] = "Could not trace into fd given by "
 	"GIT_TRACE environment variable";
 
-void trace_vprintf(const char *key, const char *fmt, va_list ap)
+static void trace_vprintf(const char *key, const char *fmt, va_list ap)
 {
 	struct strbuf buf = STRBUF_INIT;
 
@@ -75,6 +75,7 @@ void trace_vprintf(const char *key, const char *fmt, va_list ap)
 	strbuf_release(&buf);
 }
 
+__attribute__((format (printf, 2, 3)))
 static void trace_printf_key(const char *key, const char *fmt, ...)
 {
 	va_list ap;