diff --git a/src/init.cpp b/src/init.cpp
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -312,11 +312,11 @@
 }
 #endif
 
-void OnRPCStarted() {
+static void OnRPCStarted() {
     uiInterface.NotifyBlockTip.connect(&RPCNotifyBlockChange);
 }
 
-void OnRPCStopped() {
+static void OnRPCStopped() {
     uiInterface.NotifyBlockTip.disconnect(&RPCNotifyBlockChange);
     RPCNotifyBlockChange(false, nullptr);
     g_best_block_cv.notify_all();
@@ -1052,7 +1052,7 @@
 // rewritten by the reindex anyway. This ensures that vinfoBlockFile is in sync
 // with what's actually on disk by the time we start downloading, so that
 // pruning works correctly.
-void CleanupBlockRevFiles() {
+static void CleanupBlockRevFiles() {
     std::map<std::string, fs::path> mapBlockFiles;
 
     // Glob all blk?????.dat and rev?????.dat files from the blocks directory.
@@ -1089,7 +1089,8 @@
     }
 }
 
-void ThreadImport(const Config &config, std::vector<fs::path> vImportFiles) {
+static void ThreadImport(const Config &config,
+                         std::vector<fs::path> vImportFiles) {
     RenameThread("bitcoin-loadblk");
 
     {
@@ -1175,7 +1176,7 @@
  *  Ensure that Bitcoin is running in a usable environment with all
  *  necessary library support.
  */
-bool InitSanityCheck(void) {
+static bool InitSanityCheck(void) {
     if (!ECC_InitSanityCheck()) {
         InitError(
             "Elliptic curve cryptography sanity check failure. Aborting.");