diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index c86e5a8b9a6..1d766a3635e 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2014-05-22  Jakub Jelinek  <jakub@redhat.com>
+
+	* tree-streamer-in.c (unpack_ts_real_cst_value_fields): Make sure
+	all padding bits in REAL_VALUE_TYPE are cleared.
+
 2014-05-22  Maxim Kuvyrkov  <maxim.kuvyrkov@linaro.org>
 
 	Cleanup and improve multipass_dfa_lookahead_guard
diff --git a/gcc/tree-streamer-in.c b/gcc/tree-streamer-in.c
index bead1198018..97ffc1e03c5 100644
--- a/gcc/tree-streamer-in.c
+++ b/gcc/tree-streamer-in.c
@@ -168,6 +168,9 @@ unpack_ts_real_cst_value_fields (struct bitpack_d *bp, tree expr)
   REAL_VALUE_TYPE r;
   REAL_VALUE_TYPE *rp;
 
+  /* Clear all bits of the real value type so that we can later do
+     bitwise comparisons to see if two values are the same.  */
+  memset (&r, 0, sizeof r);
   r.cl = (unsigned) bp_unpack_value (bp, 2);
   r.decimal = (unsigned) bp_unpack_value (bp, 1);
   r.sign = (unsigned) bp_unpack_value (bp, 1);