Fix #7931 - Incorrect variable usage using UPDATE OR INSERT.

src/dsql/DdlNodes.epp

@@ -1661,6 +1661,7 @@ string CreateAlterFunctionNode::internalPrint(NodePrinter& printer) const
 DdlNode* CreateAlterFunctionNode::dsqlPass(DsqlCompilerScratch* dsqlScratch)
 {
 	dsqlScratch->flags |= (DsqlCompilerScratch::FLAG_BLOCK | DsqlCompilerScratch::FLAG_FUNCTION);
+	dsqlScratch->reserveInitialVarNumbers(1);
 
 	LocalDeclarationsNode::checkUniqueFieldsNames(localDeclList, &parameters, nullptr);
 
@@ -2677,6 +2678,7 @@ string CreateAlterProcedureNode::internalPrint(NodePrinter& printer) const
 DdlNode* CreateAlterProcedureNode::dsqlPass(DsqlCompilerScratch* dsqlScratch)
 {
 	dsqlScratch->flags |= (DsqlCompilerScratch::FLAG_BLOCK | DsqlCompilerScratch::FLAG_PROCEDURE);
+	dsqlScratch->reserveInitialVarNumbers(returns.getCount());
 
 	LocalDeclarationsNode::checkUniqueFieldsNames(localDeclList, &parameters, &returns);
 

src/dsql/DsqlCompilerScratch.cpp

@@ -298,8 +298,6 @@ void DsqlCompilerScratch::putLocalVariableDecl(dsql_var* variable, DeclareVariab
 	if (variable->field->fld_name.hasData())	// Not a function return value
 		putDebugVariable(variable->number, variable->field->fld_name);
 
-	++hiddenVarsNumber;
-
 	if (variable->type != dsql_var::TYPE_INPUT && hostParam && hostParam->dsqlDef->defaultClause)
 	{
 		hostParam->dsqlDef->defaultClause->value =
@@ -377,7 +375,7 @@ void DsqlCompilerScratch::putOuterMaps()
 
 // Make a variable.
 dsql_var* DsqlCompilerScratch::makeVariable(dsql_fld* field, const char* name,
-	const dsql_var::Type type, USHORT msgNumber, USHORT itemNumber, USHORT localNumber)
+	const dsql_var::Type type, USHORT msgNumber, USHORT itemNumber, std::optional<USHORT> localNumber)
 {
 	DEV_BLKCHK(field, dsql_type_fld);
 
@@ -387,7 +385,7 @@ dsql_var* DsqlCompilerScratch::makeVariable(dsql_fld* field, const char* name,
 	dsqlVar->type = type;
 	dsqlVar->msgNumber = msgNumber;
 	dsqlVar->msgItem = itemNumber;
-	dsqlVar->number = localNumber;
+	dsqlVar->number = localNumber.has_value() ? localNumber.value() : nextVarNumber++;
 	dsqlVar->field = field;
 
 	if (field)

src/dsql/DsqlCompilerScratch.h

@@ -30,6 +30,7 @@
 #include "../jrd/MetaName.h"
 #include "../common/classes/stack.h"
 #include "../common/classes/alloc.h"
+#include <optional>
 
 namespace Jrd
 {
@@ -164,7 +165,7 @@ class DsqlCompilerScratch : public BlrDebugWriter
 
 	void putOuterMaps();
 	dsql_var* makeVariable(dsql_fld*, const char*, const dsql_var::Type type, USHORT,
-		USHORT, USHORT);
+		USHORT, std::optional<USHORT> = std::nullopt);
 	dsql_var* resolveVariable(const MetaName& varName);
 	void genReturn(bool eosFlag = false);
 
@@ -178,8 +179,7 @@ class DsqlCompilerScratch : public BlrDebugWriter
 		context->clear();
 		contextNumber = 0;
 		derivedContextNumber = 0;
-
-		hiddenVarsNumber = 0;
+		nextVarNumber = 0;
 		hiddenVariables.clear();
 	}
 
@@ -234,6 +234,17 @@ class DsqlCompilerScratch : public BlrDebugWriter
 		}
 	}
 
+	USHORT reserveVarNumber()
+	{
+		return nextVarNumber++;
+	}
+
+	void reserveInitialVarNumbers(USHORT count)
+	{
+		fb_assert(nextVarNumber == 0);
+		nextVarNumber = count;
+	}
+
 	bool isPsql() const { return psql; }
 	void setPsql(bool value) { psql = value; }
 
@@ -298,7 +309,6 @@ class DsqlCompilerScratch : public BlrDebugWriter
 	bool processingWindow = false;			// processing window functions
 	bool checkConstraintTrigger = false;	// compiling a check constraint trigger
 	dsc domainValue;						// VALUE in the context of domain's check constraint
-	USHORT hiddenVarsNumber = 0;			// next hidden variable number
 	Firebird::Array<dsql_var*> hiddenVariables;	// hidden variables
 	Firebird::Array<dsql_var*> variables;
 	Firebird::Array<dsql_var*> outputVariables;
@@ -311,6 +321,7 @@ class DsqlCompilerScratch : public BlrDebugWriter
 private:
 	Firebird::HalfStaticArray<SelectExprNode*, 4> ctes; // common table expressions
 	Firebird::HalfStaticArray<const Firebird::string*, 4> cteAliases; // CTE aliases in recursive members
+	USHORT nextVarNumber = 0;				// Next available variable number
 	bool psql = false;
 	Firebird::LeftPooledMap<MetaName, DeclareSubFuncNode*> subFunctions;
 	Firebird::LeftPooledMap<MetaName, DeclareSubProcNode*> subProcedures;

src/dsql/ExprNodes.cpp

@@ -13991,7 +13991,7 @@ ValueExprNode* VariableNode::dsqlPass(DsqlCompilerScratch* dsqlScratch)
 			else
 			{
 				if (!dsqlScratch->outerVarsMap.exist(node->dsqlVar->number))
-					dsqlScratch->outerVarsMap.put(node->dsqlVar->number, dsqlScratch->hiddenVarsNumber++);
+					dsqlScratch->outerVarsMap.put(node->dsqlVar->number, dsqlScratch->reserveVarNumber());
 			}
 		}
 	}

src/dsql/StmtNodes.cpp

@@ -4950,6 +4950,7 @@ ExecBlockNode* ExecBlockNode::dsqlPass(DsqlCompilerScratch* dsqlScratch)
 		statement->setType(DsqlStatement::TYPE_EXEC_BLOCK);
 
 	dsqlScratch->flags |= DsqlCompilerScratch::FLAG_BLOCK;
+	dsqlScratch->reserveInitialVarNumbers(parameters.getCount() + returns.getCount());
 
 	ExecBlockNode* node = FB_NEW_POOL(dsqlScratch->getPool()) ExecBlockNode(dsqlScratch->getPool());
 
@@ -6128,7 +6129,6 @@ void LocalDeclarationsNode::genBlr(DsqlCompilerScratch* dsqlScratch)
 	// Sub routine doesn't need ports and should generate BLR as declared in its metadata.
 	const bool isSubRoutine = dsqlScratch->flags & DsqlCompilerScratch::FLAG_SUB_ROUTINE;
 	const auto& variables = isSubRoutine ? dsqlScratch->outputVariables : dsqlScratch->variables;
-	USHORT locals = variables.getCount();
 
 	Array<dsql_var*> declaredVariables;
 
@@ -6160,16 +6160,14 @@ void LocalDeclarationsNode::genBlr(DsqlCompilerScratch* dsqlScratch)
 			}
 
 			const auto variable = dsqlScratch->makeVariable(field, field->fld_name.c_str(),
-				dsql_var::TYPE_LOCAL, 0, 0, locals);
+				dsql_var::TYPE_LOCAL, 0, 0);
 			declaredVariables.add(variable);
 
 			dsqlScratch->putLocalVariableDecl(variable, varNode, varNode->dsqlDef->type->collate);
 
 			// Some field attributes are calculated inside putLocalVariable(), so we reinitialize
 			// the descriptor.
 			DsqlDescMaker::fromField(&variable->desc, field);
-
-			++locals;
 		}
 		else if (nodeIs<DeclareCursorNode>(parameter) ||
 			nodeIs<DeclareSubProcNode>(parameter) ||
@@ -10982,8 +10980,7 @@ static VariableNode* dsqlPassHiddenVariable(DsqlCompilerScratch* dsqlScratch, Va
 	}
 
 	VariableNode* varNode = FB_NEW_POOL(*tdbb->getDefaultPool()) VariableNode(*tdbb->getDefaultPool());
-	varNode->dsqlVar = dsqlScratch->makeVariable(NULL, "", dsql_var::TYPE_HIDDEN,
-		0, 0, dsqlScratch->hiddenVarsNumber++);
+	varNode->dsqlVar = dsqlScratch->makeVariable(nullptr, "", dsql_var::TYPE_HIDDEN, 0, 0);
 
 	DsqlDescMaker::fromNode(dsqlScratch, &varNode->dsqlVar->desc, expr);
 	varNode->setDsqlDesc(varNode->dsqlVar->desc);