diff --git a/libavformat/nutenc.c b/libavformat/nutenc.c
index df0301b5e74c08bbb84f818a610dea8c585f24e2..29b6dcdaab5c5663aa7417e2ca91450d2a4bbb53 100644
--- a/libavformat/nutenc.c
+++ b/libavformat/nutenc.c
@@ -263,13 +263,17 @@ static void put_s(AVIOContext *bc, int64_t val){
 }
 
 #ifdef TRACE
-static inline void ff_put_v_trace(AVIOContext *bc, uint64_t v, char *file, char *func, int line){
+static inline void ff_put_v_trace(AVIOContext *bc, uint64_t v, const char *file,
+                                  const char *func, int line)
+{
     av_log(NULL, AV_LOG_DEBUG, "ff_put_v %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
 
     ff_put_v(bc, v);
 }
 
-static inline void put_s_trace(AVIOContext *bc, int64_t v, char *file, char *func, int line){
+static inline void put_s_trace(AVIOContext *bc, int64_t v, const char *file,
+                               const char *func, int line)
+{
     av_log(NULL, AV_LOG_DEBUG, "put_s %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
 
     put_s(bc, v);