diff --git a/doc/sql.extensions/README.regr_functions.txt b/doc/sql.extensions/README.regr_functions.txt
index 94ee227c11..e85bf7811f 100644
--- a/doc/sql.extensions/README.regr_functions.txt
+++ b/doc/sql.extensions/README.regr_functions.txt
@@ -2,7 +2,7 @@
 Linear Regression Functions
 ---------------------------
 
-REGR_* functions analyze relationshitp of the 2 numeric set of data.
+REGR_* functions analyze relationship of the 2 numeric set of data.
 These functions calculate with records that both of 2 set are not NULL.
 
 Syntax:
diff --git a/src/dsql/AggNodes.cpp b/src/dsql/AggNodes.cpp
index 18ed042289..7df7981fb2 100644
--- a/src/dsql/AggNodes.cpp
+++ b/src/dsql/AggNodes.cpp
@@ -2237,16 +2237,15 @@ void RegrCountAggNode::aggInit(thread_db* tdbb, jrd_req* request) const
 
 bool RegrCountAggNode::aggPass(thread_db* tdbb, jrd_req* request) const
 {
+	EVL_expr(tdbb, request, arg);
+	if (request->req_flags & req_null)
+		return false;
+
+	EVL_expr(tdbb, request, arg2);
+	if (request->req_flags & req_null)
+		return false;
+
 	impure_value_ex* impure = request->getImpure<impure_value_ex>(impureOffset);
-
-	dsc* desc = EVL_expr(tdbb, request, arg);
-	if (request->req_flags & req_null)
-		return false;
-
-	dsc* desc2 = EVL_expr(tdbb, request, arg2);
-	if (request->req_flags & req_null)
-		return false;
-
 	++impure->vlu_misc.vlu_int64;
 
 	return true;
diff --git a/src/dsql/StmtNodes.cpp b/src/dsql/StmtNodes.cpp
index 80aba70926..8580cd0050 100644
--- a/src/dsql/StmtNodes.cpp
+++ b/src/dsql/StmtNodes.cpp
@@ -2007,7 +2007,6 @@ DeclareSubProcNode* DeclareSubProcNode::dsqlPass(DsqlCompilerScratch* dsqlScratc
 		for (NestConst<ParameterClause>* i = paramArray.begin(); i != paramArray.end(); ++i)
 		{
 			ParameterClause* param = *i;
-			const unsigned paramIndex = i - paramArray.begin();
 
 			SignatureParameter sigParam(pool);
 			sigParam.type = 1;	// output
diff --git a/src/dsql/WinNodes.cpp b/src/dsql/WinNodes.cpp
index 9551f58f0c..5caaca0190 100644
--- a/src/dsql/WinNodes.cpp
+++ b/src/dsql/WinNodes.cpp
@@ -256,7 +256,6 @@ dsc* PercentRankWinNode::aggExecute(thread_db* /*tdbb*/, jrd_req* request) const
 
 dsc* PercentRankWinNode::winPass(thread_db* /*tdbb*/, jrd_req* request, SlidingWindow* window) const
 {
-	impure_value_ex* impure = request->getImpure<impure_value_ex>(impureOffset);
 	impure_value_ex* impureTemp = request->getImpure<impure_value_ex>(tempImpure);
 
 	double partitionSize = window->getPartitionSize();
@@ -433,8 +432,6 @@ void FirstValueWinNode::aggInit(thread_db* tdbb, jrd_req* request) const
 
 dsc* FirstValueWinNode::winPass(thread_db* tdbb, jrd_req* request, SlidingWindow* window) const
 {
-	impure_value_ex* impure = request->getImpure<impure_value_ex>(impureOffset);
-
 	if (!window->moveWithinFrame(-(window->getRecordPosition() - window->getFrameStart())))
 		return NULL;
 
@@ -496,8 +493,6 @@ void LastValueWinNode::aggInit(thread_db* tdbb, jrd_req* request) const
 
 dsc* LastValueWinNode::winPass(thread_db* tdbb, jrd_req* request, SlidingWindow* window) const
 {
-	impure_value_ex* impure = request->getImpure<impure_value_ex>(impureOffset);
-
 	if (!window->moveWithinFrame(window->getFrameEnd() - window->getRecordPosition()))
 		return NULL;
 
@@ -573,8 +568,6 @@ void NthValueWinNode::aggInit(thread_db* tdbb, jrd_req* request) const
 
 dsc* NthValueWinNode::winPass(thread_db* tdbb, jrd_req* request, SlidingWindow* window) const
 {
-	impure_value_ex* impure = request->getImpure<impure_value_ex>(impureOffset);
-
 	dsc* desc = EVL_expr(tdbb, request, row);
 	if (!desc || (request->req_flags & req_null))
 		return NULL;
diff --git a/src/gpre/boot/gpre_meta_boot.cpp b/src/gpre/boot/gpre_meta_boot.cpp
index a153cc6d74..67f13f4011 100644
--- a/src/gpre/boot/gpre_meta_boot.cpp
+++ b/src/gpre/boot/gpre_meta_boot.cpp
@@ -41,13 +41,6 @@
 #include "../gpre/par_proto.h"
 #include "../yvalve/gds_proto.h"
 
-static const UCHAR blr_bpb[] =
-{
-	isc_bpb_version1,
-	isc_bpb_source_type, 1, isc_blob_blr,
-	isc_bpb_target_type, 1, isc_blob_blr
-};
-
 /*____________________________________________________________
  *
  *		Lookup a field by name in a context.
diff --git a/src/intl/charsets/cs_koi8r.h b/src/intl/charsets/cs_koi8r.h
index 21d928a174..0c9d1e68bd 100644
--- a/src/intl/charsets/cs_koi8r.h
+++ b/src/intl/charsets/cs_koi8r.h
@@ -263,7 +263,6 @@
    -------------------------------------------- */
 
 
-static const int UNICODE_REPLACEMENT_CHARACTER = 0xFFFD;
 static const int CANT_MAP_CHARACTER = 0;
 
 static const USHORT to_unicode_map[256] = {
diff --git a/src/jrd/exe.cpp b/src/jrd/exe.cpp
index 2722c25b32..3ab19c6d2a 100644
--- a/src/jrd/exe.cpp
+++ b/src/jrd/exe.cpp
@@ -670,8 +670,6 @@ void EXE_receive(thread_db* tdbb,
 		}
 	}
 
-	const auto statement = request->getStatement();
-
 	try
 	{
 		if (nodeIs<StallNode>(request->req_message))
@@ -818,7 +816,6 @@ void EXE_send(thread_db* tdbb, jrd_req* request, USHORT msg, ULONG length, const
 	node = request->req_message;
 
 	jrd_tra* transaction = request->req_transaction;
-	const JrdStatement* statement = request->getStatement();
 
 	const SelectNode* selectNode;
 
@@ -881,7 +878,6 @@ void EXE_start(thread_db* tdbb, jrd_req* request, jrd_tra* transaction)
 		ERR_post(Arg::Gds(isc_req_no_trans));
 
 	JrdStatement* statement = request->getStatement();
-	const jrd_prc* proc = statement->procedure;
 
 	/* Post resources to transaction block.  In particular, the interest locks
 	on relations/indices are copied to the transaction, which is very
@@ -1348,8 +1344,6 @@ const StmtNode* EXE_looper(thread_db* tdbb, jrd_req* request, const StmtNode* no
 
 	// Execute stuff until we drop
 
-	const JrdStatement* statement = request->getStatement();
-
 	while (node && !(request->req_flags & req_stall))
 	{
 		try
diff --git a/src/jrd/extds/InternalDS.cpp b/src/jrd/extds/InternalDS.cpp
index 65bea36491..2f92d71725 100644
--- a/src/jrd/extds/InternalDS.cpp
+++ b/src/jrd/extds/InternalDS.cpp
@@ -73,7 +73,6 @@ void InternalProvider::jrdAttachmentEnd(thread_db* tdbb, Attachment* att, bool f
 		return;
 
 	{	// scope
-		Database* dbb = tdbb->getDatabase();
 		MutexLockGuard guard(m_mutex, FB_FUNCTION);
 
 		AttToConnMap::Accessor acc(&m_connections);
diff --git a/src/jrd/ini.epp b/src/jrd/ini.epp
index 126c6d830f..2054ad85f5 100644
--- a/src/jrd/ini.epp
+++ b/src/jrd/ini.epp
@@ -1435,7 +1435,6 @@ static void store_global_field(thread_db* tdbb, const gfld* gfield, AutoRequest&
  *
  **************************************/
 	SET_TDBB(tdbb);
-	Database* dbb = tdbb->getDatabase();
 	Jrd::Attachment* attachment = tdbb->getAttachment();
 
 	STORE(REQUEST_HANDLE handle) X IN RDB$FIELDS
diff --git a/src/jrd/jrd.cpp b/src/jrd/jrd.cpp
index a58ef1a743..943232e654 100644
--- a/src/jrd/jrd.cpp
+++ b/src/jrd/jrd.cpp
@@ -1517,9 +1517,6 @@ void JRD_transliterate(thread_db* tdbb, Firebird::IStatus* vector) throw()
 
 const ULONG SWEEP_INTERVAL		= 20000;
 
-const char DBL_QUOTE			= '\042';
-const char SINGLE_QUOTE			= '\'';
-
 
 static void trace_warning(thread_db* tdbb, FbStatusVector* userStatus, const char* func)
 {
@@ -7460,7 +7457,6 @@ static void init_database_lock(thread_db* tdbb)
  **************************************/
 	SET_TDBB(tdbb);
 	Database* const dbb = tdbb->getDatabase();
-	Jrd::Attachment* const attachment = tdbb->getAttachment();
 
 	// Main database lock
 
@@ -8039,7 +8035,6 @@ static void purge_transactions(thread_db* tdbb, Jrd::Attachment* attachment, con
  *	from an attachment
  *
  **************************************/
-	Database* const dbb = attachment->att_database;
 	jrd_tra* const trans_dbk = attachment->att_dbkey_trans;
 
 	if (force_flag)
diff --git a/src/jrd/opt.cpp b/src/jrd/opt.cpp
index 72acb6439d..7199c7b03f 100644
--- a/src/jrd/opt.cpp
+++ b/src/jrd/opt.cpp
@@ -363,11 +363,11 @@ static void sort_indices_by_selectivity(CompilerScratch::csb_repeat* csbTail);
 // macro definitions
 
 #ifdef OPT_DEBUG
-const int DEBUG_PUNT			= 5;
-const int DEBUG_RELATIONSHIPS	= 4;
-const int DEBUG_ALL				= 3;
-const int DEBUG_CANDIDATE		= 2;
-const int DEBUG_BEST			= 1;
+//const int DEBUG_PUNT			= 5;
+//const int DEBUG_RELATIONSHIPS	= 4;
+//const int DEBUG_ALL			= 3;
+//const int DEBUG_CANDIDATE		= 2;
+//const int DEBUG_BEST			= 1;
 const int DEBUG_NONE			= 0;
 
 FILE *opt_debug_file = 0;
diff --git a/src/jrd/recsrc/RecordSource.cpp b/src/jrd/recsrc/RecordSource.cpp
index 484d9bc897..a9740f3f0f 100644
--- a/src/jrd/recsrc/RecordSource.cpp
+++ b/src/jrd/recsrc/RecordSource.cpp
@@ -119,7 +119,6 @@ void RecordSource::printInversion(thread_db* tdbb, const InversionNode* inversio
 	case InversionNode::TYPE_INDEX:
 		{
 			const IndexRetrieval* const retrieval = inversion->retrieval;
-			const jrd_rel* const relation = retrieval->irb_relation;
 
 			MetaName indexName;
 			if (retrieval->irb_name && retrieval->irb_name->hasData())
diff --git a/src/jrd/vio.cpp b/src/jrd/vio.cpp
index 4bab00dc26..98ea16e6d0 100644
--- a/src/jrd/vio.cpp
+++ b/src/jrd/vio.cpp
@@ -1462,7 +1462,7 @@ static bool check_prepare_result(int prepare_result, jrd_tra* transaction, jrd_r
  **************************************
  *
  * Functional description
- *	Called by VIO_modify and VIO_erase. Raise update conflict error if not in 
+ *	Called by VIO_modify and VIO_erase. Raise update conflict error if not in
  *  read consistency transaction or lock error happens or if request is already
  *  in update conflict mode. In latter case set TRA_ex_restart flag to correctly
  *  handle request restart.
@@ -1473,17 +1473,17 @@ static bool check_prepare_result(int prepare_result, jrd_tra* transaction, jrd_r
 
 	jrd_req* top_request = request->req_snapshot.m_owner;
 
-	const bool restart_ready = top_request && 
+	const bool restart_ready = top_request &&
 		(top_request->req_flags & req_restart_ready);
 
 	// Second update conflict when request is already in update conflict mode
-	// means we have some (indirect) UPDATE\DELETE in WHERE clause of primary 
+	// means we have some (indirect) UPDATE\DELETE in WHERE clause of primary
 	// cursor. In this case all we can do is restart whole request immediately.
-	const bool secondary = top_request && 
-		(top_request->req_flags & req_update_conflict) && 
+	const bool secondary = top_request &&
+		(top_request->req_flags & req_update_conflict) &&
 		(prepare_result != PREPARE_LOCKERR);
 
-	if (!(transaction->tra_flags & TRA_read_consistency) || prepare_result == PREPARE_LOCKERR || 
+	if (!(transaction->tra_flags & TRA_read_consistency) || prepare_result == PREPARE_LOCKERR ||
 		secondary || !restart_ready)
 	{
 		if (secondary)
@@ -1898,7 +1898,7 @@ bool VIO_erase(thread_db* tdbb, record_param* rpb, jrd_tra* transaction)
 			verb_post(tdbb, transaction, rpb, rpb->rpb_undo);
 
 		// We have INSERT + DELETE or UPDATE + DELETE in the same transaction.
-		// UPDATE has already notified GC, while INSERT has not. Check for 
+		// UPDATE has already notified GC, while INSERT has not. Check for
 		// backversion allows to avoid second notification in case of UPDATE.
 
 		if ((dbb->dbb_flags & DBB_gc_background) && !rpb->rpb_relation->isTemporary() && !backVersion)
@@ -3219,7 +3219,7 @@ bool VIO_modify(thread_db* tdbb, record_param* org_rpb, record_param* new_rpb, j
 	const bool backVersion = (org_rpb->rpb_b_page != 0);
 	record_param temp;
 	PageStack stack;
-	int prepare_result = prepare_update(tdbb, transaction, org_rpb->rpb_transaction_nr, org_rpb, 
+	int prepare_result = prepare_update(tdbb, transaction, org_rpb->rpb_transaction_nr, org_rpb,
 										&temp, new_rpb, stack, false);
 	if (!check_prepare_result(prepare_result, transaction, tdbb->getRequest(), org_rpb))
 		return false;
@@ -5533,7 +5533,6 @@ static int prepare_update(	thread_db*		tdbb,
  **************************************/
 	SET_TDBB(tdbb);
 
-	Attachment* const attachment = tdbb->getAttachment();
 	jrd_rel* const relation = rpb->rpb_relation;
 
 #ifdef VIO_DEBUG