diff --git a/doc/APIchanges b/doc/APIchanges
index a1eecea9fd..fb2b1440fb 100644
--- a/doc/APIchanges
+++ b/doc/APIchanges
@@ -2,6 +2,9 @@ The last version increases of all libraries were on 2023-02-09
 
 API changes, most recent first:
 
+2024-02-28 - xxxxxxxxxx - lavu 58.40.100 - timestamp.h
+  av_ts_make_time_string() now accepts a pointer to const AVRational.
+
 2024-02-28 - xxxxxxxxxx - lavf 60.23.100 - avio.h
   avio_print_string_array() now accepts an array of const pointers.
 
diff --git a/libavutil/timestamp.h b/libavutil/timestamp.h
index 9ae64da8a1..2b37781eba 100644
--- a/libavutil/timestamp.h
+++ b/libavutil/timestamp.h
@@ -62,7 +62,8 @@ static inline char *av_ts_make_string(char *buf, int64_t ts)
  * @param tb the timebase of the timestamp
  * @return the buffer in input
  */
-static inline char *av_ts_make_time_string(char *buf, int64_t ts, AVRational *tb)
+static inline char *av_ts_make_time_string(char *buf, int64_t ts,
+                                           const AVRational *tb)
 {
     if (ts == AV_NOPTS_VALUE) snprintf(buf, AV_TS_MAX_STRING_SIZE, "NOPTS");
     else                      snprintf(buf, AV_TS_MAX_STRING_SIZE, "%.6g", av_q2d(*tb) * ts);
diff --git a/libavutil/version.h b/libavutil/version.h
index 9f45af93df..3fbc292a68 100644
--- a/libavutil/version.h
+++ b/libavutil/version.h
@@ -79,7 +79,7 @@
  */
 
 #define LIBAVUTIL_VERSION_MAJOR  58
-#define LIBAVUTIL_VERSION_MINOR  39
+#define LIBAVUTIL_VERSION_MINOR  40
 #define LIBAVUTIL_VERSION_MICRO 100
 
 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \