diff --git a/src/estream-printf.c b/src/estream-printf.c
--- a/src/estream-printf.c
+++ b/src/estream-printf.c
@@ -1499,6 +1499,7 @@
 
   int myerrno = errno; /* Save the errno for use with "%m". */
 
+  memset (valuetable_buffer, 0, sizeof valuetable_buffer);
 
   /* Parse the arguments to come up with descriptive list.  We can't
      do this on the fly because we need to support positional