diff --git a/src/primitives/transaction.h b/src/primitives/transaction.h
--- a/src/primitives/transaction.h
+++ b/src/primitives/transaction.h
@@ -25,7 +25,9 @@
     uint32_t n;
 
 public:
-    COutPoint() : txid(), n(-1) {}
+    static constexpr uint32_t NULL_INDEX = std::numeric_limits<uint32_t>::max();
+
+    COutPoint() : txid(), n(NULL_INDEX) {}
     COutPoint(TxId txidIn, uint32_t nIn) : txid(txidIn), n(nIn) {}
 
     ADD_SERIALIZE_METHODS;
@@ -36,7 +38,7 @@
         READWRITE(n);
     }
 
-    bool IsNull() const { return txid.IsNull() && n == uint32_t(-1); }
+    bool IsNull() const { return txid.IsNull() && n == NULL_INDEX; }
 
     const TxId &GetTxId() const { return txid; }
     uint32_t GetN() const { return n; }
diff --git a/src/streams.h b/src/streams.h
--- a/src/streams.h
+++ b/src/streams.h
@@ -746,7 +746,8 @@
     CBufferedFile(FILE *fileIn, uint64_t nBufSize, uint64_t nRewindIn,
                   int nTypeIn, int nVersionIn)
         : nType(nTypeIn), nVersion(nVersionIn), nSrcPos(0), nReadPos(0),
-          nReadLimit((uint64_t)(-1)), nRewind(nRewindIn), vchBuf(nBufSize, 0) {
+          nReadLimit(std::numeric_limits<uint64_t>::max()), nRewind(nRewindIn),
+          vchBuf(nBufSize, 0) {
         src = fileIn;
     }
 
@@ -828,7 +829,7 @@
     }
 
     // Prevent reading beyond a certain position. No argument removes the limit.
-    bool SetLimit(uint64_t nPos = (uint64_t)(-1)) {
+    bool SetLimit(uint64_t nPos = std::numeric_limits<uint64_t>::max()) {
         if (nPos < nReadPos) {
             return false;
         }
diff --git a/src/test/serialize_tests.cpp b/src/test/serialize_tests.cpp
--- a/src/test/serialize_tests.cpp
+++ b/src/test/serialize_tests.cpp
@@ -206,7 +206,7 @@
     }
 
     for (uint64_t i = 0; i < 100000000000ULL; i += 999999937) {
-        uint64_t j = -1;
+        uint64_t j = std::numeric_limits<uint64_t>::max();
         ss >> VARINT(j);
         BOOST_CHECK_MESSAGE(i == j, "decoded:" << j << " expected:" << i);
     }