diff --git a/src/yvalve/PluginManager.cpp b/src/yvalve/PluginManager.cpp
index 02babaaf9a..0cbc0a767c 100644
--- a/src/yvalve/PluginManager.cpp
+++ b/src/yvalve/PluginManager.cpp
@@ -66,7 +66,7 @@ namespace
 		list.ltrim(" \t,;");
 	}
 
-	void extension(PathName& file, const char* newExt)
+	void changeExtension(PathName& file, const char* newExt)
 	{
 		PathName::size_type p = file.rfind(PathUtils::dir_sep);
 		if (p == PathName::npos)
@@ -89,7 +89,7 @@ namespace
 	class StaticConfHolder
 	{
 	public:
-		StaticConfHolder(MemoryPool&)
+		explicit StaticConfHolder(MemoryPool&)
 			: confFile(FB_NEW(*getDefaultMemoryPool()) ConfigFile(*getDefaultMemoryPool(),
 				fb_utils::getPrefix(fb_utils::FB_DIR_CONF, "plugins.conf"), ConfigFile::HAS_SUB_CONF))
 		{
@@ -356,7 +356,7 @@ namespace
 
 	struct CountByTypeArray
 	{
-		CountByTypeArray(MemoryPool&)
+		explicit CountByTypeArray(MemoryPool&)
 		{}
 
 		CountByType values[PluginType::MaxType];
@@ -539,7 +539,7 @@ namespace
 			}
 		}
 
-		Mutex mutex;
+		Mutex mutex; // locked by this class' destructor and by objects that use the plugins var below.
 		Semaphore* wakeIt;
 	};
 
@@ -715,7 +715,7 @@ namespace
 			}
 
 			PathName plugConfigFile = curModule;
-			extension(plugConfigFile, "conf");
+			changeExtension(plugConfigFile, "conf");
 
 			currentPlugin = new ConfiguredPlugin(m, r, conf, plugConfigFile, currentName);
 
@@ -815,7 +815,7 @@ void FB_CARG PluginManager::registerPlugin(unsigned int interfaceType, const cha
 	if (current == builtin)
 	{
 		PathName plugConfigFile = fb_utils::getPrefix(fb_utils::FB_DIR_PLUGINS, defaultName);
-		extension(plugConfigFile, "conf");
+		changeExtension(plugConfigFile, "conf");
 
 		ConfiguredPlugin* p = new ConfiguredPlugin(RefPtr<PluginModule>(builtin), r,
 									findConfig("Plugin", defaultName), plugConfigFile, defaultName);
diff --git a/src/yvalve/utl.cpp b/src/yvalve/utl.cpp
index 44d35e0ed8..d7c7b51f0c 100644
--- a/src/yvalve/utl.cpp
+++ b/src/yvalve/utl.cpp
@@ -2132,7 +2132,7 @@ int API_ROUTINE gds__thread_start(FPTR_INT_VOID_PTR entrypoint,
 
 	int rc = 0;
 	try {
-		Thread::start((ThreadEntryPoint*)entrypoint, arg, priority, (Thread::Handle*)thd_id);
+		Thread::start((ThreadEntryPoint*) entrypoint, arg, priority, (Thread::Handle*) thd_id);
 	}
 	catch (const Firebird::status_exception& status) {
 		rc = status.value()[1];
diff --git a/src/yvalve/why.cpp b/src/yvalve/why.cpp
index 720ca6189a..bc59d5a36b 100644
--- a/src/yvalve/why.cpp
+++ b/src/yvalve/why.cpp
@@ -2828,7 +2828,7 @@ ISC_STATUS API_ROUTINE isc_dsql_exec_immediate(ISC_STATUS* user_status,
 {
 /**************************************
  *
- *	i s c _ d s q l _ e x e c _ i m m e d
+ *	i s c _ d s q l _ e x e c _ i m m e d i a t e
  *
  **************************************
  *
@@ -3044,7 +3044,8 @@ ISC_STATUS API_ROUTINE isc_dsql_exec_immed2_m(ISC_STATUS* user_status,
 		}
 
 		bool ret_v3_error = false;
-		if (!stmt_eaten) {
+		if (!stmt_eaten)
+		{
 			// Check if against < 4.0 database
 
 			const SCHAR ch = isc_info_base_level;
@@ -3064,7 +3065,8 @@ ISC_STATUS API_ROUTINE isc_dsql_exec_immed2_m(ISC_STATUS* user_status,
 			}
 		}
 
-		if (status[1]) {
+		if (status[1])
+		{
 			isc_rollback_transaction(temp_status, &crdb_trans_handle);
 			save_error_string(status);
 			isc_drop_database(temp_status, db_handle);
@@ -3072,7 +3074,8 @@ ISC_STATUS API_ROUTINE isc_dsql_exec_immed2_m(ISC_STATUS* user_status,
 			return status[1];
 		}
 
-		if (isc_commit_transaction(status, &crdb_trans_handle)) {
+		if (isc_commit_transaction(status, &crdb_trans_handle))
+		{
 			isc_rollback_transaction(temp_status, &crdb_trans_handle);
 			save_error_string(status);
 			isc_drop_database(temp_status, db_handle);
@@ -4805,7 +4808,6 @@ ISC_STATUS API_ROUTINE isc_start_multiple(ISC_STATUS* user_status,
  *
  **************************************/
 	TEB* vector = (TEB*) vec;
-	ISC_STATUS_ARRAY temp;
 	Transaction transaction(NULL);
 	Attachment attachment(NULL);