diff --git a/contrib/epee/include/net/abstract_tcp_server2.inl b/contrib/epee/include/net/abstract_tcp_server2.inl
index 8d96e4a84..240ef3bc4 100644
--- a/contrib/epee/include/net/abstract_tcp_server2.inl
+++ b/contrib/epee/include/net/abstract_tcp_server2.inl
@@ -50,6 +50,8 @@
 #include <sstream>
 #include <iomanip>
 #include <algorithm>
+#include <functional>
+#include <random>
 
 #undef MONERO_DEFAULT_LOG_CATEGORY
 #define MONERO_DEFAULT_LOG_CATEGORY "net"
@@ -628,7 +630,17 @@ PRAGMA_WARNING_DISABLE_VS(4355)
             return false; // aborted
         }*/
 
-        long int ms = 250 + (rand()%50);
+        using engine = std::mt19937;
+
+        engine rng;
+        std::random_device dev;
+        std::seed_seq::result_type rand[engine::state_size]{};  // Use complete bit space
+
+        std::generate_n(rand, engine::state_size, std::ref(dev));
+        std::seed_seq seed(rand, rand + engine::state_size);
+        rng.seed(seed);
+
+        long int ms = 250 + (rng() % 50);
         MDEBUG("Sleeping because QUEUE is FULL, in " << __FUNCTION__ << " for " << ms << " ms before packet_size="<<chunk.size()); // XXX debug sleep
         m_send_que_lock.unlock();
         boost::this_thread::sleep(boost::posix_time::milliseconds( ms ) );
diff --git a/contrib/epee/src/connection_basic.cpp b/contrib/epee/src/connection_basic.cpp
index 7526dde26..3ce7a1057 100644
--- a/contrib/epee/src/connection_basic.cpp
+++ b/contrib/epee/src/connection_basic.cpp
@@ -136,6 +136,7 @@ connection_basic::connection_basic(boost::asio::ip::tcp::socket&& sock, std::sha
 	socket_(GET_IO_SERVICE(sock), get_context(m_state.get())),
 	m_want_close_connection(false),
 	m_was_shutdown(false),
+	m_is_multithreaded(false),
 	m_ssl_support(ssl_support)
 {
 	// add nullptr checks if removed
@@ -160,6 +161,7 @@ connection_basic::connection_basic(boost::asio::io_service &io_service, std::sha
 	socket_(io_service, get_context(m_state.get())),
 	m_want_close_connection(false),
 	m_was_shutdown(false),
+	m_is_multithreaded(false),
 	m_ssl_support(ssl_support)
 {
 	// add nullptr checks if removed
diff --git a/src/rpc/bootstrap_daemon.cpp b/src/rpc/bootstrap_daemon.cpp
index 6f8426ee7..c97b2c95a 100644
--- a/src/rpc/bootstrap_daemon.cpp
+++ b/src/rpc/bootstrap_daemon.cpp
@@ -12,7 +12,7 @@
 namespace cryptonote
 {
 
-  bootstrap_daemon::bootstrap_daemon(std::function<boost::optional<std::string>()> get_next_public_node) noexcept
+  bootstrap_daemon::bootstrap_daemon(std::function<boost::optional<std::string>()> get_next_public_node)
     : m_get_next_public_node(get_next_public_node)
   {
   }
diff --git a/src/rpc/bootstrap_daemon.h b/src/rpc/bootstrap_daemon.h
index 130a6458d..6276b1b21 100644
--- a/src/rpc/bootstrap_daemon.h
+++ b/src/rpc/bootstrap_daemon.h
@@ -15,7 +15,7 @@ namespace cryptonote
   class bootstrap_daemon
   {
   public:
-    bootstrap_daemon(std::function<boost::optional<std::string>()> get_next_public_node) noexcept;
+    bootstrap_daemon(std::function<boost::optional<std::string>()> get_next_public_node);
     bootstrap_daemon(const std::string &address, const boost::optional<epee::net_utils::http::login> &credentials);
 
     std::string address() const noexcept;
diff --git a/src/wallet/wallet2.cpp b/src/wallet/wallet2.cpp
index b85e805de..3e00369a8 100644
--- a/src/wallet/wallet2.cpp
+++ b/src/wallet/wallet2.cpp
@@ -13195,6 +13195,12 @@ bool wallet2::save_to_file(const std::string& path_to_file, const std::string& r
   }
 
   FILE *fp = fopen(path_to_file.c_str(), "w+");
+  if (!fp)
+  {
+    MERROR("Failed to open wallet file for writing: " << path_to_file << ": " << strerror(errno));
+    return false;
+  }
+
   // Save the result b/c we need to close the fp before returning success/failure.
   int write_result = PEM_write(fp, ASCII_OUTPUT_MAGIC.c_str(), "", (const unsigned char *) raw.c_str(), raw.length());
   fclose(fp);
diff --git a/tests/performance_tests/rct_mlsag.h b/tests/performance_tests/rct_mlsag.h
index 59eae074e..da0c064fd 100644
--- a/tests/performance_tests/rct_mlsag.h
+++ b/tests/performance_tests/rct_mlsag.h
@@ -82,6 +82,6 @@ public:
 private:
   rct::keyV sk;
   rct::keyM P;
-  size_t ind;
+  size_t ind{};
   rct::mgSig IIccss;
 };