diff --git a/libavformat/cache.c b/libavformat/cache.c
index 3e60aea48fbea0041f924856b6b796ea35ffb577..900554a82adf327ce0abb96824de7ee149896dcb 100644
--- a/libavformat/cache.c
+++ b/libavformat/cache.c
@@ -51,7 +51,7 @@ typedef struct Context {
 
 static int cache_open(URLContext *h, const char *arg, int flags)
 {
-    const char *buffername;
+    char *buffername;
     Context *c= h->priv_data;
 
     av_strstart(arg, "cache:", &arg);