diff --git a/doc/sql.extensions/README.ddl_triggers.txt b/doc/sql.extensions/README.ddl_triggers.txt
index e326591574..4e01a5b848 100644
--- a/doc/sql.extensions/README.ddl_triggers.txt
+++ b/doc/sql.extensions/README.ddl_triggers.txt
@@ -91,7 +91,7 @@ Semantics:
 	   FUNCTION} triggers.
 
 Notes:
-	1) COMMENT ON, GRANT, REVOKE and ALTER DATABASE does not fire DDL triggers.
+	1) COMMENT ON, GRANT, REVOKE and ALTER DATABASE do not fire DDL triggers.
 
 Utilities support:
 	DDL triggers is a type of database triggers, so the parameters -nodbtriggers (GBAK and ISQL)
diff --git a/src/dsql/ExprNodes.cpp b/src/dsql/ExprNodes.cpp
index f74b6b2b85..11bfc891d7 100644
--- a/src/dsql/ExprNodes.cpp
+++ b/src/dsql/ExprNodes.cpp
@@ -1508,7 +1508,7 @@ dsc* ArithmeticNode::add(const dsc* desc, impure_value* value, const ValueExprNo
 
 	const SLONG l1 = MOV_get_long(desc, node->nodScale);
 	const SINT64 l2 = MOV_get_long(&value->vlu_desc, node->nodScale);
-	SINT64 rc = (blrOp == blr_subtract) ? l2 - l1 : l2 + l1;
+	const SINT64 rc = (blrOp == blr_subtract) ? l2 - l1 : l2 + l1;
 
 	if (rc < MIN_SLONG || rc > MAX_SLONG)
 		ERR_post(Arg::Gds(isc_exception_integer_overflow));
@@ -10395,7 +10395,8 @@ DmlNode* UdfCallNode::parse(thread_db* tdbb, MemoryPool& pool, CompilerScratch*
 		csb->csb_blr_reader.setPos(savePos);
 		return SysFuncCallNode::parse(tdbb, pool, csb, blr_sys_function);
 	}
-	else if (blrOp == blr_subfunc)
+
+	if (blrOp == blr_subfunc)
 	{
 		DeclareSubFuncNode* declareNode;
 		if (csb->subFunctions.get(name.identifier, declareNode))
diff --git a/src/jrd/opt.cpp b/src/jrd/opt.cpp
index 28e8f03878..42d04dedd7 100644
--- a/src/jrd/opt.cpp
+++ b/src/jrd/opt.cpp
@@ -689,7 +689,7 @@ RecordSource* OPT_compile(thread_db* tdbb, CompilerScratch* csb, RseNode* rse,
 			nodeBase = opt->opt_base_conjuncts;
 		}
 
-		fb_assert(nodeBase >= 0 && j >= 0);
+		fb_assert(nodeBase >= 0 && j >= 0 && nodeBase + j < MAX_CONJUNCTS);
 		opt->opt_conjuncts[nodeBase + j].opt_conjunct_node = node;
 	}