diff --git a/src/bench/base58.cpp b/src/bench/base58.cpp
index 8f6d07ac166d4..2d9a9f29087e7 100644
--- a/src/bench/base58.cpp
+++ b/src/bench/base58.cpp
@@ -22,7 +22,7 @@ static void Base58Encode(benchmark::State& state)
         }
     };
     while (state.KeepRunning()) {
-        EncodeBase58(buff.begin(), buff.end());
+        EncodeBase58(buff.data(), buff.data() + buff.size());
     }
 }
 
diff --git a/src/bench/checkqueue.cpp b/src/bench/checkqueue.cpp
index 7e63e820db1e7..35750aa1b69f2 100644
--- a/src/bench/checkqueue.cpp
+++ b/src/bench/checkqueue.cpp
@@ -19,7 +19,7 @@ static const int MIN_CORES = 2;
 static const size_t BATCHES = 101;
 static const size_t BATCH_SIZE = 30;
 static const int PREVECTOR_SIZE = 28;
-static const int QUEUE_BATCH_SIZE = 128;
+static const unsigned int QUEUE_BATCH_SIZE = 128;
 static void CCheckQueueSpeed(benchmark::State& state)
 {
     struct FakeJobNoWork {
diff --git a/src/chainparams.cpp b/src/chainparams.cpp
index 079bf1b1f729b..69a6ca4c2c07b 100644
--- a/src/chainparams.cpp
+++ b/src/chainparams.cpp
@@ -429,9 +429,9 @@ class CMainParams : public CChainParams {
 
         nStakeMinAge = 24 * 60 * 60; // 24 hours
 
-        checkpointData = (CCheckpointData) {
+        checkpointData = {
             {
-                {0, uint256S("0x000006cf010a54f22305095939df01cc5d7a2ecd208e1e353259a75cd99f58b4")},
+                {0, uint256S("0x00000ce07df018e65e003f4d097cf026db99bcd493d6c4d07f0b47edf6534a26")},
             }
         };
 
@@ -594,9 +594,9 @@ class CTestNetParams : public CChainParams {
 
         nStakeMinAge = 24 * 60 * 60; // 24 hours
 
-        checkpointData = (CCheckpointData) {
+        checkpointData = {
             {
-                {0, uint256S("0x00000d08a9828c9e2c4c95996e1a3895e24de49d0b62ef595486a428d727cede")},
+                {0, uint256S("0x0000030f02c1f2473c1b3d7988b7d83a5e2cde4b2b69fe1612befdcbcb8eb70f")},
             }
         };
 
@@ -758,7 +758,7 @@ class CDevNetParams : public CChainParams {
 
         nStakeMinAge = 24 * 60 * 60; // 24 hours
 
-        checkpointData = (CCheckpointData) {
+        checkpointData = {
             {
                 { 1, devnetGenesis.GetHash() },
             }
@@ -879,9 +879,9 @@ class CRegTestParams : public CChainParams {
 
         nStakeMinAge = 24 * 60 * 60; // 24 hours
 
-        checkpointData = (CCheckpointData) {
+        checkpointData = {
             {
-                {0, uint256S("0x00000d204dc7f3c855835549afbf59d8002502ae2b56bc46826ca41b7bfc5651")},
+                {0, uint256S("0x02fc1e7262651eb1027ef489dae355c0ca063bc4832ca4b6d41d18216268835c")},
             }
         };
 
diff --git a/src/compat.h b/src/compat.h
index 0494fe89f14ab..8b1037e1aa0de 100644
--- a/src/compat.h
+++ b/src/compat.h
@@ -41,6 +41,7 @@
 #include <mswsock.h>
 #include <windows.h>
 #include <ws2tcpip.h>
+#include <stdint.h>
 #else
 #include <sys/fcntl.h>
 #include <sys/mman.h>
@@ -81,6 +82,15 @@ typedef unsigned int SOCKET;
 #else
 #define MAX_PATH            1024
 #endif
+#ifdef _MSC_VER
+#if !defined(ssize_t)
+#ifdef _WIN64
+typedef int64_t ssize_t;
+#else
+typedef int32_t ssize_t;
+#endif
+#endif
+#endif
 
 #if HAVE_DECL_STRNLEN == 0
 size_t strnlen( const char *start, size_t max_len);
diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index ec9871f0f46ca..4ce91e57df6cf 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -63,7 +63,7 @@ std::atomic<int64_t> nTimeBestReceived(0); // Used only to inform the wallet of
 struct IteratorComparator
 {
     template<typename I>
-    bool operator()(const I& a, const I& b)
+    bool operator()(const I& a, const I& b) const
     {
         return &(*a) < &(*b);
     }
diff --git a/src/random.h b/src/random.h
index e1e0be82a0729..ff009047a1c4d 100644
--- a/src/random.h
+++ b/src/random.h
@@ -138,7 +138,7 @@ class FastRandomContext {
  * sure that the underlying OS APIs for all platforms support the number.
  * (many cap out at 256 bytes).
  */
-static const ssize_t NUM_OS_RANDOM_BYTES = 32;
+static const int NUM_OS_RANDOM_BYTES = 32;
 
 /** Get 32 bytes of system entropy. Do not use this in application code: use
  * GetStrongRandBytes instead.
diff --git a/src/support/cleanse.cpp b/src/support/cleanse.cpp
index 82cdfe707bb2a..8d3c7369b4950 100644
--- a/src/support/cleanse.cpp
+++ b/src/support/cleanse.cpp
@@ -7,6 +7,10 @@
 
 #include <cstring>
 
+#if defined(_MSC_VER)
+#include <Windows.h> // For SecureZeroMemory.
+#endif
+
 /* Compilers have a bad habit of removing "superfluous" memset calls that
  * are trying to zero memory. For example, when memset()ing a buffer and
  * then free()ing it, the compiler might decide that the memset is
@@ -32,7 +36,7 @@ void memory_cleanse(void *ptr, size_t len)
        might try to eliminate "superfluous" memsets. If there's an easy way to
        detect memset_s, it would be better to use that. */
 #if defined(_MSC_VER)
-    __asm;
+    SecureZeroMemory(ptr, len);
 #else
     __asm__ __volatile__("" : : "r"(ptr) : "memory");
 #endif
diff --git a/src/test/checkqueue_tests.cpp b/src/test/checkqueue_tests.cpp
index 64e14b8c6609e..81dde1c2b8587 100644
--- a/src/test/checkqueue_tests.cpp
+++ b/src/test/checkqueue_tests.cpp
@@ -24,7 +24,7 @@
 // otherwise.
 BOOST_FIXTURE_TEST_SUITE(checkqueue_tests, TestingSetup)
 
-static const int QUEUE_BATCH_SIZE = 128;
+static const unsigned int QUEUE_BATCH_SIZE = 128;
 
 struct FakeCheck {
     bool operator()()