diff --git a/doc/release-notes.md b/doc/release-notes.md
index 806d174eb..8360cc481 100644
--- a/doc/release-notes.md
+++ b/doc/release-notes.md
@@ -21,6 +21,13 @@ It is recommended to use this for sensitive information such as wallet
 passphrases, as command-line arguments can usually be read from the process
 table by any user on the system.
 
+RPC low-level changes
+----------------------
+
+- `gettxoutsetinfo` UTXO hash (`hash_serialized`) has changed. There was a divergence between
+  32-bit and 64-bit platforms, and the txids were missing in the hashed data. This has been
+  fixed, but this means that the output will be different than from previous versions.
+
 0.13.0 Change log
 =================
 
diff --git a/src/crypto/ripemd160.h b/src/crypto/ripemd160.h
index 687204fda..bd41f0250 100644
--- a/src/crypto/ripemd160.h
+++ b/src/crypto/ripemd160.h
@@ -14,7 +14,7 @@ class CRIPEMD160
 private:
     uint32_t s[5];
     unsigned char buf[64];
-    size_t bytes;
+    uint64_t bytes;
 
 public:
     static const size_t OUTPUT_SIZE = 20;
diff --git a/src/crypto/sha1.h b/src/crypto/sha1.h
index 7b2a21bc6..8fb20810b 100644
--- a/src/crypto/sha1.h
+++ b/src/crypto/sha1.h
@@ -14,7 +14,7 @@ class CSHA1
 private:
     uint32_t s[5];
     unsigned char buf[64];
-    size_t bytes;
+    uint64_t bytes;
 
 public:
     static const size_t OUTPUT_SIZE = 20;
diff --git a/src/crypto/sha256.h b/src/crypto/sha256.h
index 85cf33739..5b15b6a23 100644
--- a/src/crypto/sha256.h
+++ b/src/crypto/sha256.h
@@ -14,7 +14,7 @@ class CSHA256
 private:
     uint32_t s[8];
     unsigned char buf[64];
-    size_t bytes;
+    uint64_t bytes;
 
 public:
     static const size_t OUTPUT_SIZE = 32;
diff --git a/src/crypto/sha512.h b/src/crypto/sha512.h
index f1f17caf9..614681fae 100644
--- a/src/crypto/sha512.h
+++ b/src/crypto/sha512.h
@@ -14,7 +14,7 @@ class CSHA512
 private:
     uint64_t s[8];
     unsigned char buf[128];
-    size_t bytes;
+    uint64_t bytes;
 
 public:
     static const size_t OUTPUT_SIZE = 64;
diff --git a/src/rpc/blockchain.cpp b/src/rpc/blockchain.cpp
index b85b2f6b5..88f6278b2 100644
--- a/src/rpc/blockchain.cpp
+++ b/src/rpc/blockchain.cpp
@@ -467,6 +467,7 @@ static bool GetUTXOStats(CCoinsView *view, CCoinsStats &stats)
         CCoins coins;
         if (pcursor->GetKey(key) && pcursor->GetValue(coins)) {
             stats.nTransactions++;
+            ss << key;
             for (unsigned int i=0; i<coins.vout.size(); i++) {
                 const CTxOut &out = coins.vout[i];
                 if (!out.IsNull()) {