Unload ib_util.dll (.so) when unloading the engine.

src/jrd/fun.epp

@@ -31,6 +31,7 @@
  */
 
 #include "firebird.h"
+#include <atomic>
 #include <cmath>
 #include <stdlib.h>
 #include <stdio.h>
@@ -78,7 +79,8 @@ using namespace Firebird;
 
 namespace
 {
-	bool volatile initDone = false;
+	const ModuleLoader::Module* bootModule = reinterpret_cast<ModuleLoader::Module*>(0x1);
+	std::atomic<const ModuleLoader::Module*> ibUtilModule;
 
 	struct IbUtilStartup
 	{
@@ -123,7 +125,7 @@ namespace
 		}
 
 		ibUtilUnit(IbUtil::alloc);
-		initDone = true;
+		ibUtilModule = module;
 
 		return true;
 	}
@@ -132,9 +134,12 @@ namespace
 
 void IbUtil::initialize()
 {
-	if (initDone || fb_utils::bootBuild())
+	if (ibUtilModule)
+		return;
+
+	if (fb_utils::bootBuild())
 	{
-		initDone = true;
+		ibUtilModule = bootModule;
 		return;
 	}
 
@@ -172,6 +177,16 @@ void IbUtil::initialize()
 									   message[2].c_str(), message[3].c_str());
 }
 
+void IbUtil::finalize()
+{
+	const ModuleLoader::Module* module = ibUtilModule.exchange(nullptr);
+
+	if (!module || module == bootModule)
+		return;
+
+	delete module;
+}
+
 void* IbUtil::alloc(long size)
 {
 	thread_db* tdbb = JRD_get_thread_data();
@@ -318,7 +333,7 @@ void FUN_evaluate(thread_db* tdbb, const Function* function, const NestValueArra
  *
  **************************************/
 	// We may be in danger of AV in UDF if ib_util init failed
-	if (!initDone)
+	if (!ibUtilModule)
 	{
 		ERR_post(Arg::Gds(isc_random) << "ib_util init failed - UDF usage disabled");
 	}

src/jrd/fun_proto.h

@@ -31,6 +31,7 @@ class IbUtil
 {
 public:
 	static void initialize();
+	static void finalize();
 
 	static void* alloc(long size);
 	static bool free(void* ptr);

src/jrd/jrd.cpp

@@ -4654,6 +4654,7 @@ void JProvider::shutdown(CheckStatusWrapper* status, unsigned int timeout, const
 			// PluginManager wants to lock a mutex, which is sometimes already locked in current thread
 			TraceManager::shutdown();
 			Mapping::shutdownIpc();
+			IbUtil::finalize();
 		}
 
 		// Wait for completion of all attacment shutdown threads