Subject: fix a resource leak of comments on input parsing failure
From: Helmut Grohne <helmut () subdivi de>

--- a/src/formats.c
+++ b/src/formats.c
@@ -572,6 +572,7 @@ error:
   free(ft->priv);
   free(ft->filename);
   free(ft->filetype);
+  sox_delete_comments(&ft->oob.comments);
   free(ft);
   return NULL;
 }