1 files changed, 1 insertions, 1 deletions
diff --git a/lib/md5.h b/lib/md5.h
index 12b3a5e8f..63cc70e84 100644
--- a/lib/md5.h
+++ b/lib/md5.h
@@ -24,6 +24,6 @@
  ***************************************************************************/
 
 void Curl_md5it(unsigned char *output,
-                unsigned char *input);
+                const unsigned char *input);
 
 #endif