diff --git a/src/bench/crypto_hash.cpp b/src/bench/crypto_hash.cpp
--- a/src/bench/crypto_hash.cpp
+++ b/src/bench/crypto_hash.cpp
@@ -66,7 +66,7 @@
 
 static void FastRandom_32bit(benchmark::State &state) {
     FastRandomContext rng(true);
-    uint32_t x;
+    uint32_t x = 0;
     while (state.KeepRunning()) {
         for (int i = 0; i < 1000000; i++) {
             x += rng.rand32();
@@ -76,7 +76,7 @@
 
 static void FastRandom_1bit(benchmark::State &state) {
     FastRandomContext rng(true);
-    uint32_t x;
+    uint32_t x = 0;
     while (state.KeepRunning()) {
         for (int i = 0; i < 1000000; i++) {
             x += rng.randbool();
diff --git a/src/qt/paymentserver.cpp b/src/qt/paymentserver.cpp
--- a/src/qt/paymentserver.cpp
+++ b/src/qt/paymentserver.cpp
@@ -239,9 +239,9 @@
 // message()", but "QMessageBox::"!
 //
 void PaymentServer::ipcParseCommandLine(int argc, char *argv[]) {
-    std::array<const std::string *, 3> networks = {&CBaseChainParams::MAIN,
-                                                   &CBaseChainParams::TESTNET,
-                                                   &CBaseChainParams::REGTEST};
+    std::array<const std::string *, 3> networks = {
+        {&CBaseChainParams::MAIN, &CBaseChainParams::TESTNET,
+         &CBaseChainParams::REGTEST}};
 
     const std::string *chosenNetwork = nullptr;
 
diff --git a/src/seeder/bitcoin.cpp b/src/seeder/bitcoin.cpp
--- a/src/seeder/bitcoin.cpp
+++ b/src/seeder/bitcoin.cpp
@@ -13,7 +13,7 @@
 bool fTestNet;
 
 // The network magic to use.
-CMessageHeader::MessageMagic netMagic = {0xe3, 0xe1, 0xf3, 0xe8};
+CMessageHeader::MessageMagic netMagic = {{0xe3, 0xe1, 0xf3, 0xe8}};
 
 #define BITCOIN_SEED_NONCE 0x0539a019ca550825ULL
 
diff --git a/src/test/amount_tests.cpp b/src/test/amount_tests.cpp
--- a/src/test/amount_tests.cpp
+++ b/src/test/amount_tests.cpp
@@ -84,7 +84,7 @@
 }
 
 BOOST_AUTO_TEST_CASE(AmountTests) {
-    std::array<int64_t, 8> values = {-23, -1, 0, 1, 2, 3, 42, 99999999};
+    std::array<int64_t, 8> values = {{-23, -1, 0, 1, 2, 3, 42, 99999999}};
 
     for (int64_t i : values) {
         for (int64_t j : values) {
diff --git a/src/test/monolith_opcodes.cpp b/src/test/monolith_opcodes.cpp
--- a/src/test/monolith_opcodes.cpp
+++ b/src/test/monolith_opcodes.cpp
@@ -14,8 +14,8 @@
 typedef std::vector<uint8_t> valtype;
 typedef std::vector<valtype> stacktype;
 
-std::array<uint32_t, 3> flagset{0, STANDARD_SCRIPT_VERIFY_FLAGS,
-                                MANDATORY_SCRIPT_VERIFY_FLAGS};
+std::array<uint32_t, 3> flagset{
+    {0, STANDARD_SCRIPT_VERIFY_FLAGS, MANDATORY_SCRIPT_VERIFY_FLAGS}};
 
 BOOST_FIXTURE_TEST_SUITE(monolith_opcodes_tests, BasicTestingSetup)
 
diff --git a/src/test/test_bitcoin_fuzzy.cpp b/src/test/test_bitcoin_fuzzy.cpp
--- a/src/test/test_bitcoin_fuzzy.cpp
+++ b/src/test/test_bitcoin_fuzzy.cpp
@@ -192,8 +192,8 @@
             break;
         }
         case CMESSAGEHEADER_DESERIALIZE: {
-            CMessageHeader::MessageMagic pchMessageStart = {0x00, 0x00, 0x00,
-                                                            0x00};
+            CMessageHeader::MessageMagic pchMessageStart = {
+                {0x00, 0x00, 0x00, 0x00}};
             try {
                 CMessageHeader mh(pchMessageStart);
                 ds >> mh;
diff --git a/src/txdb.cpp b/src/txdb.cpp
--- a/src/txdb.cpp
+++ b/src/txdb.cpp
@@ -49,7 +49,7 @@
         s >> key;
         uint256 id;
         s >> id;
-        uint32_t n;
+        uint32_t n = 0;
         s >> VARINT(n);
         *outpoint = COutPoint(id, n);
     }