fixup! Warn when layout base is near the end of storage

Author: cameel

libsolidity/analysis/PostTypeContractLevelChecker.cpp

@@ -29,6 +29,8 @@
 #include <libsolutil/FunctionSelector.h>
 #include <liblangutil/ErrorReporter.h>
 
+#include <range/v3/action/reverse.hpp>
+
 #include <limits>
 
 using namespace solidity;
@@ -148,6 +150,21 @@ void PostTypeContractLevelChecker::checkStorageLayoutSpecifier(ContractDefinitio
 		);
 }
 
+namespace
+{
+
+VariableDeclaration const* findLastStorageVariable(ContractDefinition const& _contract)
+{
+	for (ContractDefinition const* baseContract: ranges::actions::reverse(_contract.annotation().linearizedBaseContracts))
+		for (VariableDeclaration const* stateVariable: ranges::actions::reverse(baseContract->stateVariables()))
+			if (stateVariable->referenceLocation() == VariableDeclaration::Location::Unspecified)
+				return stateVariable;
+
+	return nullptr;
+}
+
+}
+
 void PostTypeContractLevelChecker::warnStorageLayoutBaseNearStorageEnd(ContractDefinition const& _contract)
 {
 	// In case of most errors the warning is pointless. E.g. if we're already past storage end.
@@ -168,9 +185,11 @@ void PostTypeContractLevelChecker::warnStorageLayoutBaseNearStorageEnd(ContractD
 			_contract.storageLayoutSpecifier()->location() :
 			_contract.location();
 
+		VariableDeclaration const* lastStorageVariable = findLastStorageVariable(_contract);
+
 		auto errorID = 3495_error;
 		std::string errorMsg = "This contract is very close to the end of storage. This limits its future upgradability.";
-		if (_contract.stateVariables().size() > 0)
+		if (lastStorageVariable)
 			m_errorReporter.warning(
 				errorID,
 				location,
@@ -180,7 +199,7 @@ void PostTypeContractLevelChecker::warnStorageLayoutBaseNearStorageEnd(ContractD
 						"There are {} storage slots between this state variable and the end of storage.",
 						formatNumberReadable(slotsLeft)
 					),
-					_contract.stateVariables().back()->location()
+					lastStorageVariable->location()
 				)
 			);
 		else