Merge pull request #10023 from ethereum/develop

Merge develop into breaking.

Changelog.md

@@ -22,6 +22,8 @@ Language Features:
 
 Compiler Features:
  * SMTChecker: Support inline arrays.
+ * Control Flow Graph: Print warning for non-empty functions with unnamed return parameters that are not assigned a value in all code paths.
+
 
 Bugfixes:
  * Code generator: Fix internal compiler error when referencing members via module name but not using the reference.

docs/contracts/functions.rst

@@ -424,6 +424,8 @@ operations as long as there is enough gas passed on to it.
             // If someone sends Ether to that contract, the receive function in TestPayable will be called.
             require(address(test).send(2 ether));
             // results in test.x becoming == 2 and test.y becoming 2 ether.
+
+            return true;
         }
     }
 

libsolidity/analysis/ControlFlowAnalyzer.cpp

@@ -37,13 +37,13 @@ bool ControlFlowAnalyzer::visit(FunctionDefinition const& _function)
 	if (_function.isImplemented())
 	{
 		auto const& functionFlow = m_cfg.functionFlow(_function);
-		checkUninitializedAccess(functionFlow.entry, functionFlow.exit);
+		checkUninitializedAccess(functionFlow.entry, functionFlow.exit, _function.body().statements().empty());
 		checkUnreachable(functionFlow.entry, functionFlow.exit, functionFlow.revert, functionFlow.transactionReturn);
 	}
 	return false;
 }
 
-void ControlFlowAnalyzer::checkUninitializedAccess(CFGNode const* _entry, CFGNode const* _exit) const
+void ControlFlowAnalyzer::checkUninitializedAccess(CFGNode const* _entry, CFGNode const* _exit, bool _emptyBody) const
 {
 	struct NodeInfo
 	{
@@ -95,10 +95,6 @@ void ControlFlowAnalyzer::checkUninitializedAccess(CFGNode const* _entry, CFGNod
 				case VariableOccurrence::Kind::Return:
 					if (unassignedVariables.count(&variableOccurrence.declaration()))
 					{
-						if (
-							variableOccurrence.declaration().type()->dataStoredIn(DataLocation::Storage) ||
-							variableOccurrence.declaration().type()->dataStoredIn(DataLocation::CallData)
-						)
 						// Merely store the unassigned access. We do not generate an error right away, since this
 						// path might still always revert. It is only an error if this is propagated to the exit
 						// node of the function (i.e. there is a path with an uninitialized access).
@@ -140,6 +136,8 @@ void ControlFlowAnalyzer::checkUninitializedAccess(CFGNode const* _entry, CFGNod
 				ssl.append("The variable was declared here.", variableOccurrence->declaration().location());
 
 			bool isStorage = variableOccurrence->declaration().type()->dataStoredIn(DataLocation::Storage);
+			bool isCalldata = variableOccurrence->declaration().type()->dataStoredIn(DataLocation::CallData);
+			if (isStorage || isCalldata)
 				m_errorReporter.typeError(
 					3464_error,
 					variableOccurrence->occurrence() ?
@@ -152,6 +150,12 @@ void ControlFlowAnalyzer::checkUninitializedAccess(CFGNode const* _entry, CFGNod
 					(variableOccurrence->kind() == VariableOccurrence::Kind::Return ? "returned" : "accessed") +
 					" without prior assignment, which would lead to undefined behaviour."
 				);
+			else if (!_emptyBody && variableOccurrence->declaration().name().empty())
+				m_errorReporter.warning(
+					6321_error,
+					variableOccurrence->declaration().location(),
+					"Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable."
+				);
 		}
 	}
 }

libsolidity/analysis/ControlFlowAnalyzer.h

@@ -36,7 +36,7 @@ public:
 
 private:
 	/// Checks for uninitialized variable accesses in the control flow between @param _entry and @param _exit.
-	void checkUninitializedAccess(CFGNode const* _entry, CFGNode const* _exit) const;
+	void checkUninitializedAccess(CFGNode const* _entry, CFGNode const* _exit, bool _emptyBody) const;
 	/// Checks for unreachable code, i.e. code ending in @param _exit, @param _revert or @param _transactionReturn
 	/// that can not be reached from @param _entry.
 	void checkUnreachable(CFGNode const* _entry, CFGNode const* _exit, CFGNode const* _revert, CFGNode const* _transactionReturn) const;

libsolidity/formal/PredicateInstance.cpp

@@ -64,7 +64,7 @@ smtutil::Expression constructor(Predicate const& _pred, ContractDefinition const
 		return _pred(currentFunctionVariables(*constructor, &_contract, _context));
 
 	auto& state = _context.state();
-	vector<smtutil::Expression> stateExprs{state.errorFlag().currentValue(), state.thisAddress(0), state.state()};
+	vector<smtutil::Expression> stateExprs{state.errorFlag().currentValue(), state.thisAddress(0), state.state(0), state.state()};
 	return _pred(stateExprs + currentStateVariables(_contract, _context));
 }
 

libsolidity/formal/PredicateSort.cpp

@@ -60,7 +60,7 @@ SortPointer constructorSort(ContractDefinition const& _contract, SymbolicState&
 		return functionSort(*constructor, &_contract, _state);
 
 	return make_shared<FunctionSort>(
-		vector<SortPointer>{_state.errorFlagSort(), _state.thisAddressSort(), _state.stateSort()} + stateSorts(_contract),
+		vector<SortPointer>{_state.errorFlagSort(), _state.thisAddressSort(), _state.stateSort(), _state.stateSort()} + stateSorts(_contract),
 		SortProvider::boolSort
 	);
 }

libyul/optimiser/StackToMemoryMover.cpp

@@ -49,6 +49,23 @@ vector<Statement> generateMemoryStore(
 	}});
 	return result;
 }
+
+FunctionCall generateMemoryLoad(Dialect const& _dialect, langutil::SourceLocation const& _loc, YulString _mpos)
+{
+	BuiltinFunction const* memoryLoadFunction = _dialect.memoryLoadFunction(_dialect.defaultType);
+	yulAssert(memoryLoadFunction, "");
+	return FunctionCall{
+		_loc,
+		Identifier{_loc, memoryLoadFunction->name}, {
+			Literal{
+				_loc,
+				LiteralKind::Number,
+				_mpos,
+				{}
+			}
+		}
+	};
+}
 }
 
 void StackToMemoryMover::run(
@@ -93,29 +110,34 @@ void StackToMemoryMover::operator()(FunctionDefinition& _functionDefinition)
 void StackToMemoryMover::operator()(Block& _block)
 {
 	using OptionalStatements = std::optional<vector<Statement>>;
-	auto containsVariableNeedingEscalation = [&](auto const& _variables) {
+	auto rewriteAssignmentOrVariableDeclaration = [&](
-		return util::contains_if(_variables, [&](auto const& var) {
+		auto& _stmt,
+		auto const& _variables
+	) -> OptionalStatements {
+		using StatementType = decay_t<decltype(_stmt)>;
+		if (_stmt.value)
+			visit(*_stmt.value);
+		bool leftHandSideNeedsMoving = util::contains_if(_variables, [&](auto const& var) {
 			return m_memoryOffsetTracker(var.name);
 		});
-	};
+		if (!leftHandSideNeedsMoving)
-	auto rewriteAssignmentOrVariableDeclaration = [&](
+			return {};
-		langutil::SourceLocation const& _loc,
+
-		auto const& _variables,
+		langutil::SourceLocation loc = _stmt.location;
-		std::unique_ptr<Expression> _value
+
-	) -> std::vector<Statement> {
 		if (_variables.size() == 1)
 		{
 			optional<YulString> offset = m_memoryOffsetTracker(_variables.front().name);
 			yulAssert(offset, "");
 			return generateMemoryStore(
 				m_context.dialect,
-				_loc,
+				loc,
 				*offset,
-				_value ? *std::move(_value) : Literal{_loc, LiteralKind::Number, "0"_yulstring, {}}
+				_stmt.value ? *std::move(_stmt.value) : Literal{loc, LiteralKind::Number, "0"_yulstring, {}}
 			);
 		}
 
-		VariableDeclaration tempDecl{_loc, {}, std::move(_value)};
+		VariableDeclaration tempDecl{loc, {}, std::move(_stmt.value)};
 		vector<Statement> memoryAssignments;
 		vector<Statement> variableAssignments;
 		for (auto& var: _variables)
@@ -126,19 +148,14 @@ void StackToMemoryMover::operator()(Block& _block)
 			if (optional<YulString> offset = m_memoryOffsetTracker(var.name))
 				memoryAssignments += generateMemoryStore(
 					m_context.dialect,
-					_loc,
+					loc,
 					*offset,
-					Identifier{_loc, tempVarName}
+					Identifier{loc, tempVarName}
 				);
-			else if constexpr (std::is_same_v<std::decay_t<decltype(var)>, Identifier>)
-				variableAssignments.emplace_back(Assignment{
-					_loc, { Identifier{var.location, var.name} },
-					make_unique<Expression>(Identifier{_loc, tempVarName})
-				});
 			else
-				variableAssignments.emplace_back(VariableDeclaration{
+				variableAssignments.emplace_back(StatementType{
-					_loc, {std::move(var)},
+					loc, {move(var)},
-					make_unique<Expression>(Identifier{_loc, tempVarName})
+					make_unique<Expression>(Identifier{loc, tempVarName})
 				});
 		}
 		std::vector<Statement> result;
@@ -147,65 +164,34 @@ void StackToMemoryMover::operator()(Block& _block)
 		result += std::move(memoryAssignments);
 		std::reverse(variableAssignments.begin(), variableAssignments.end());
 		result += std::move(variableAssignments);
-		return result;
+		return OptionalStatements{move(result)};
 	};
 
 	util::iterateReplacing(
 		_block.statements,
 		[&](Statement& _statement)
 		{
-			auto defaultVisit = [&]() { ASTModifier::visit(_statement); return OptionalStatements{}; };
 			return std::visit(util::GenericVisitor{
 				[&](Assignment& _assignment) -> OptionalStatements
 				{
-					if (!containsVariableNeedingEscalation(_assignment.variableNames))
+					return rewriteAssignmentOrVariableDeclaration(_assignment, _assignment.variableNames);
-						return defaultVisit();
-					visit(*_assignment.value);
-					return {rewriteAssignmentOrVariableDeclaration(
-						_assignment.location,
-						_assignment.variableNames,
-						std::move(_assignment.value)
-					)};
 				},
 				[&](VariableDeclaration& _varDecl) -> OptionalStatements
 				{
-					if (!containsVariableNeedingEscalation(_varDecl.variables))
+					return rewriteAssignmentOrVariableDeclaration(_varDecl, _varDecl.variables);
-						return defaultVisit();
-					if (_varDecl.value)
-						visit(*_varDecl.value);
-					return {rewriteAssignmentOrVariableDeclaration(
-						_varDecl.location,
-						_varDecl.variables,
-						std::move(_varDecl.value)
-					)};
 				},
-				[&](auto&) { return defaultVisit(); }
+				[&](auto& _stmt) -> OptionalStatements { (*this)(_stmt); return {}; }
 			}, _statement);
-		});
+		}
+	);
 }
 
 void StackToMemoryMover::visit(Expression& _expression)
 {
+	ASTModifier::visit(_expression);
 	if (Identifier* identifier = std::get_if<Identifier>(&_expression))
 		if (optional<YulString> offset = m_memoryOffsetTracker(identifier->name))
-		{
+			_expression = generateMemoryLoad(m_context.dialect, identifier->location, *offset);
-			BuiltinFunction const* memoryLoadFunction = m_context.dialect.memoryLoadFunction(m_context.dialect.defaultType);
-			yulAssert(memoryLoadFunction, "");
-			langutil::SourceLocation loc = identifier->location;
-			_expression = FunctionCall{
-				loc,
-				Identifier{loc, memoryLoadFunction->name}, {
-					Literal{
-						loc,
-						LiteralKind::Number,
-						*offset,
-						{}
-					}
-				}
-			};
-			return;
-		}
-	ASTModifier::visit(_expression);
 }
 
 optional<YulString> StackToMemoryMover::VariableMemoryOffsetTracker::operator()(YulString _variable) const

libyul/optimiser/Suite.cpp

@@ -126,7 +126,7 @@ void OptimiserSuite::run(
 	{
 		yulAssert(_meter, "");
 		ConstantOptimiser{*dialect, *_meter}(ast);
-		if (dialect->providesObjectAccess())
+		if (dialect->providesObjectAccess() && _optimizeStackAllocation)
 			StackLimitEvader::run(suite.m_context, _object, CompilabilityChecker{
 				_dialect,
 				_object,

test/cmdlineTests/optimizer_array_sload/input.sol

@@ -4,8 +4,8 @@ pragma solidity >=0.0;
 contract Arraysum {
 	uint256[] values;
 
-	function sumArray() public view returns(uint) {
+	function sumArray() public view returns(uint sum) {
-		uint sum = 0;
+		sum = 0;
 		// The optimizer should read the length of the array only once, because
 		// LoopInvariantCodeMotion can move the `sload` corresponding to the length outside of the
 		// loop.

test/cmdlineTests/optimizer_array_sload/output

@@ -43,7 +43,7 @@ object "Arraysum_33" {
                             vloc_sum := add(vloc_sum, _3)
                         }
                         let memPos := allocateMemory(_1)
-                        return(memPos, sub(abi_encode_uint(memPos, _1), memPos))
+                        return(memPos, sub(abi_encode_uint(memPos, vloc_sum), memPos))
                     }
                 }
                 revert(0, 0)

test/libsolidity/smtCheckerTests/complex/warn_on_struct.sol

@@ -7,6 +7,7 @@ contract C {
     }
 }
 // ----
+// Warning 6321: (117-121): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 2072: (133-143): Unused local variable.
 // Warning 8364: (146-147): Assertion checker does not yet implement type type(struct C.A storage pointer)
 // Warning 4639: (146-163): Assertion checker does not yet implement this expression.

test/libsolidity/smtCheckerTests/control_flow/require.sol

@@ -30,4 +30,5 @@ contract C {
 	}
 }
 // ----
+// Warning 6321: (429-442): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 6328: (448-465): CHC: Assertion violation happens here.

test/libsolidity/smtCheckerTests/control_flow/revert.sol

@@ -32,4 +32,5 @@ contract C {
 // ----
 // Warning 5740: (116-129): Unreachable code.
 // Warning 5740: (221-234): Unreachable code.
+// Warning 6321: (408-421): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 6328: (427-444): CHC: Assertion violation happens here.

test/libsolidity/smtCheckerTests/control_flow/try_catch_1.sol

@@ -8,5 +8,6 @@ contract C {
 // ====
 // EVMVersion: >=byzantium
 // ----
+// Warning 6321: (75-79): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 7645: (98-121): Assertion checker does not support try/catch clauses.
 // Warning 7645: (124-159): Assertion checker does not support try/catch clauses.

test/libsolidity/smtCheckerTests/functions/function_external_call_should_not_inline_1.sol

@@ -13,3 +13,4 @@ contract C {
 	}
 }
 // ----
+// Warning 6321: (85-89): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/smtCheckerTests/functions/internal_call_state_var_init_2.sol

@@ -7,3 +7,4 @@ contract c {
 	bool b = (f() > 0) || (f() > 0);
 }
 // ----
+// Warning 6321: (86-90): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/smtCheckerTests/functions/recursive_multi_return.sol

@@ -9,3 +9,5 @@ contract C {
 }
 //
 // ----
+// Warning 6321: (81-85): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (87-91): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/smtCheckerTests/functions/recursive_multi_return_2.sol

@@ -23,5 +23,18 @@ a;
 	}
 }
 // ----
+// Warning 6321: (163-167): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (171-175): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (179-183): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (187-191): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (195-199): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (203-207): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (211-215): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (219-223): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (227-231): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (235-239): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (241-244): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (246-250): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (252-259): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 6133: (72-90): Statement has no effect.
 // Warning 6133: (96-107): Statement has no effect.

test/libsolidity/smtCheckerTests/math/addmod_mulmod_zero.sol

@@ -21,6 +21,7 @@ contract C {
 	}
 }
 // ----
+// Warning 6321: (253-260): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 1218: (94-109): CHC: Error trying to invoke SMT solver.
 // Warning 1218: (113-126): CHC: Error trying to invoke SMT solver.
 // Warning 1218: (180-195): CHC: Error trying to invoke SMT solver.

test/libsolidity/smtCheckerTests/operators/compound_bitwise_and_fixed_bytes.sol

@@ -11,4 +11,5 @@ contract C {
     }
 }
 // ----
+// Warning 6321: (83-87): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 6328: (203-217): CHC: Assertion violation happens here.

test/libsolidity/smtCheckerTests/operators/compound_bitwise_or_fixed_bytes.sol

@@ -11,4 +11,5 @@ contract C {
     }
 }
 // ----
+// Warning 6321: (83-87): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 6328: (203-217): CHC: Assertion violation happens here.

test/libsolidity/smtCheckerTests/operators/compound_bitwise_xor_fixed_bytes.sol

@@ -11,4 +11,5 @@ contract C {
     }
 }
 // ----
+// Warning 6321: (83-87): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 6328: (204-221): CHC: Assertion violation happens here.

test/libsolidity/smtCheckerTests/overflow/overflow_sum_signed.sol

@@ -14,6 +14,7 @@ contract C
 	}
 }
 // ----
+// Warning 6321: (87-91): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 4984: (117-122): CHC: Overflow (resulting value larger than 127) happens here.
 // Warning 4984: (151-158): CHC: Overflow (resulting value larger than 127) happens here.
 // Warning 3944: (197-205): CHC: Underflow (resulting value less than -128) happens here.

test/libsolidity/smtCheckerTests/special/event.sol

@@ -25,4 +25,6 @@ contract C {
 	}
 }
 // ----
+// Warning 6321: (280-284): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (430-434): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 6328: (440-449): CHC: Assertion violation happens here.

test/libsolidity/smtCheckerTests/special/log.sol

@@ -36,4 +36,5 @@ contract C {
 	}
 }
 // ----
+// Warning 6321: (655-662): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 6328: (668-677): CHC: Assertion violation happens here.

test/libsolidity/smtCheckerTests/types/no_effect_statements.sol

@@ -10,6 +10,7 @@ contract test {
     }
 }
 // ----
+// Warning 6321: (115-119): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 6133: (125-126): Statement has no effect.
 // Warning 6133: (130-136): Statement has no effect.
 // Warning 6133: (140-144): Statement has no effect.

test/libsolidity/smtCheckerTests/types/rational_large_1.sol

@@ -7,4 +7,5 @@ contract c {
 	}
 }
 // ----
+// Warning 6321: (80-84): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 6328: (128-142): CHC: Assertion violation happens here.

test/libsolidity/smtCheckerTests/types/tuple_different_count_assignment_1.sol

@@ -8,4 +8,5 @@ contract C {
 	}
 }
 // ----
+// Warning 6321: (79-82): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 6328: (157-171): CHC: Assertion violation happens here.

test/libsolidity/smtCheckerTests/types/tuple_different_count_assignment_2.sol

@@ -8,4 +8,5 @@ contract C {
 	}
 }
 // ----
+// Warning 6321: (79-82): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 6328: (159-173): CHC: Assertion violation happens here.

test/libsolidity/smtCheckerTests/types/tuple_extra_parens_1.sol

@@ -5,3 +5,5 @@ contract C {
 		((, a)) = (1, 2);
 	}
 }
+// ----
+// Warning 6321: (80-83): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/smtCheckerTests/types/tuple_extra_parens_2.sol

@@ -5,3 +5,5 @@ contract C {
 		(((, a),)) = ((1, 2), 3);
 	}
 }
+// ----
+// Warning 6321: (80-83): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/smtCheckerTests/types/tuple_extra_parens_3.sol

@@ -5,3 +5,5 @@ contract C {
 		(((((((, a),)))))) = ((1, 2), 3);
 	}
 }
+// ----
+// Warning 6321: (80-83): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/smtCheckerTests/types/tuple_extra_parens_4.sol

@@ -5,3 +5,5 @@ contract C {
 		((((((, a)))),)) = ((1, 2), 3);
 	}
 }
+// ----
+// Warning 6321: (80-83): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/smtCheckerTests/types/tuple_extra_parens_5.sol

@@ -5,3 +5,5 @@ contract C {
 		((((((((((((, a))))))),))))) = ((1, 2), 3);
 	}
 }
+// ----
+// Warning 6321: (80-83): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/abiEncoder/v2_accessing_returned_dynamic_array_with_returndata_support.sol

@@ -10,4 +10,5 @@ contract C {
 // ====
 // EVMVersion: >=byzantium
 // ----
+// Warning 6321: (150-154): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 2072: (166-183): Unused local variable.

test/libsolidity/syntaxTests/controlFlow/storageReturn/default_location.sol

@@ -17,3 +17,4 @@ contract C {
     }
 }
 // ----
+// Warning 6321: (399-407): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/dataLocations/function_return_parameters_with_data_location_fine.sol

@@ -4,3 +4,6 @@ contract C {
     function h() public pure returns(uint[] memory) {}
     function i() external pure returns(uint[] memory) {}
 }
+// ----
+// Warning 6321: (51-64): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (134-147): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/freeFunctions/qualified_struct_access.sol

@@ -4,4 +4,5 @@ contract C {
     struct S { uint x; }
 }
 // ----
+// Warning 6321: (22-26): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // TypeError 3464: (45-46): This variable is of storage pointer type and can be accessed without prior assignment, which would lead to undefined behaviour.

test/libsolidity/syntaxTests/metaTypes/typeOfContract.sol

@@ -4,4 +4,5 @@ contract Test {
     }
 }
 // ----
+// Warning 6321: (54-66): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 6133: (78-88): Statement has no effect.

test/libsolidity/syntaxTests/multiVariableDeclaration/multiSingleVariableDeclaration.sol

@@ -4,3 +4,5 @@ contract C {
     a;
   }
 }
+// ----
+// Warning 6321: (46-50): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/multiVariableDeclaration/multiVariableDeclarationComplex.sol

@@ -9,3 +9,7 @@ contract C {
   function g() internal pure returns (uint, uint, uint, D.S[20] storage x, uint) { x = x; }
 }
 // ----
+// Warning 6321: (176-180): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (182-186): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (188-192): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (213-217): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/multiVariableDeclaration/multiVariableDeclarationSimple.sol

@@ -10,3 +10,8 @@ contract C {
   function h() internal pure returns (bytes memory, string storage s) { s = s; }
 }
 // ----
+// Warning 6321: (51-55): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (57-61): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (63-67): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (69-73): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (250-262): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/nameAndTypeResolution/018_forward_function_reference.sol

@@ -8,3 +8,5 @@ contract Second {
         if (First(2).fun() == true) return 1;
     }
 }
+// ----
+// Warning 6321: (183-187): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/nameAndTypeResolution/no_effect_statements.sol

@@ -9,6 +9,7 @@ contract test {
     }
 }
 // ----
+// Warning 6321: (83-87): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 6133: (93-94): Statement has no effect.
 // Warning 6133: (98-104): Statement has no effect.
 // Warning 6133: (108-112): Statement has no effect.

test/libsolidity/syntaxTests/parsing/address_payable_function_type.sol

@@ -4,3 +4,5 @@ contract C {
         function (address payable) payable external returns (address payable) h; h;
     }
 }
+// ----
+// Warning 6321: (197-267): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/parsing/if_statement.sol

@@ -4,5 +4,6 @@ contract test {
     }
 }
 // ----
+// Warning 6321: (60-64): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 2072: (109-115): Unused local variable.
 // Warning 2018: (20-128): Function state mutability can be restricted to pure

test/libsolidity/syntaxTests/tryCatch/almost_call_options.sol

@@ -11,4 +11,6 @@ contract C {
 // ====
 // EVMVersion: >=byzantium
 // ----
+// Warning 6321: (73-77): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (79-83): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 2072: (122-134): Unused local variable.

test/libsolidity/syntaxTests/tryCatch/catch_error.sol

@@ -9,3 +9,6 @@ contract C {
 }
 // ====
 // EVMVersion: >=byzantium
+// ----
+// Warning 6321: (46-50): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (52-56): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/tryCatch/catch_error_named.sol

@@ -9,3 +9,6 @@ contract C {
 }
 // ====
 // EVMVersion: >=byzantium
+// ----
+// Warning 6321: (46-50): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (52-56): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/tryCatch/catch_low_level.sol

@@ -9,3 +9,6 @@ contract C {
 }
 // ====
 // EVMVersion: >=byzantium
+// ----
+// Warning 6321: (46-50): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (52-56): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/tryCatch/no_returns.sol

@@ -7,3 +7,6 @@ contract C {
         }
     }
 }
+// ----
+// Warning 6321: (46-50): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (52-56): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/tryCatch/returns.sol

@@ -8,3 +8,6 @@ contract C {
         }
     }
 }
+// ----
+// Warning 6321: (46-50): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (52-56): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/tryCatch/returns_memory.sol

@@ -9,3 +9,6 @@ contract C {
 }
 // ====
 // EVMVersion: >=byzantium
+// ----
+// Warning 6321: (46-59): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (61-65): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/tryCatch/returns_memory_anonymous.sol

@@ -9,3 +9,6 @@ contract C {
 }
 // ====
 // EVMVersion: >=byzantium
+// ----
+// Warning 6321: (46-59): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (61-65): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/tryCatch/two_catch_clauses.sol

@@ -12,3 +12,6 @@ contract C {
 }
 // ====
 // EVMVersion: >=byzantium
+// ----
+// Warning 6321: (46-50): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (52-56): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/tupleAssignments/large_component_count.sol

@@ -21,3 +21,6 @@ contract C {
 	}
 }
 // ----
+// Warning 6321: (194-198): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (200-204): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (206-213): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/types/function_types/selector/local_variable_selector_not_pure.sol

@@ -6,3 +6,5 @@ contract C {
         g.selector;
     }
 }
+// ----
+// Warning 6321: (51-57): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/viewPureChecker/call_internal_functions_success.sol

@@ -4,3 +4,5 @@ contract C {
     function h() public { h(); g(); f(); }
     function i() payable public { i(); h(); g(); f(); }
 }
+// ----
+// Warning 6321: (89-93): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/util/BytesUtils.cpp

@@ -218,7 +218,7 @@ string BytesUtils::formatRawBytes(
 	auto it = _bytes.begin();
 
 	if (_bytes.size() != ContractABIUtils::encodingSize(_parameters))
-		parameters = ContractABIUtils::defaultParameters(ceil(_bytes.size() / 32));
+		parameters = ContractABIUtils::defaultParameters((_bytes.size() + 31) / 32);
 	else
 		parameters = _parameters;
 
@@ -320,7 +320,7 @@ string BytesUtils::formatBytesRange(
 	auto it = _bytes.begin();
 
 	if (_bytes.size() != ContractABIUtils::encodingSize(_parameters))
-		parameters = ContractABIUtils::defaultParameters(ceil(_bytes.size() / 32));
+		parameters = ContractABIUtils::defaultParameters((_bytes.size() + 31) / 32);
 	else
 		parameters = _parameters;
 

test/libsolidity/util/ContractABIUtils.cpp

@@ -20,6 +20,9 @@
 
 #include <test/libsolidity/util/SoltestErrors.h>
 
+#include <libsolutil/FunctionSelector.h>
+#include <libsolutil/CommonData.h>
+
 #include <liblangutil/Common.h>
 
 #include <boost/algorithm/string.hpp>
@@ -314,24 +317,35 @@ solidity::frontend::test::ParameterList ContractABIUtils::defaultParameters(size
 	return parameters;
 }
 
-solidity::frontend::test::ParameterList ContractABIUtils::failureParameters(bytes const _bytes)
+solidity::frontend::test::ParameterList ContractABIUtils::failureParameters(bytes const& _bytes)
+{
+	if (_bytes.empty())
+		return {};
+	else if (_bytes.size() < 4)
+		return {Parameter{bytes(), "", ABIType{ABIType::HexString, ABIType::AlignNone, _bytes.size()}, FormatInfo{}}};
+	else
 	{
 		ParameterList parameters;
-
 		parameters.push_back(Parameter{bytes(), "", ABIType{ABIType::HexString, ABIType::AlignNone, 4}, FormatInfo{}});
-	if (_bytes.size() > 4)
+
+		uint64_t selector = fromBigEndian<uint64_t>(bytes{_bytes.begin(), _bytes.begin() + 4});
+		if (selector == selectorFromSignature32("Panic(uint256)"))
+			parameters.push_back(Parameter{bytes(), "", ABIType{ABIType::Hex}, FormatInfo{}});
+		else if (selector == selectorFromSignature32("Error(string)"))
 		{
 			parameters.push_back(Parameter{bytes(), "", ABIType{ABIType::Hex}, FormatInfo{}});
 			parameters.push_back(Parameter{bytes(), "", ABIType{ABIType::UnsignedDec}, FormatInfo{}});
-	}
-
 			/// If _bytes contains at least a 1 byte message (function selector + tail pointer + message length + message)
 			/// append an additional string parameter to represent that message.
 			if (_bytes.size() > 68)
 				parameters.push_back(Parameter{bytes(), "", ABIType{ABIType::String}, FormatInfo{}});
-
+		}
+		else
+			for (size_t i = 4; i < _bytes.size(); i += 32)
+				parameters.push_back(Parameter{bytes(), "", ABIType{ABIType::HexString, ABIType::AlignNone, 32}, FormatInfo{}});
 		return parameters;
 	}
+}
 
 size_t ContractABIUtils::encodingSize(
 	solidity::frontend::test::ParameterList const& _parameters

test/libsolidity/util/ContractABIUtils.h

@@ -65,7 +65,7 @@ public:
 	/// returned values in case of a failure. Creates an additional parameter
 	/// for the error message if _bytes is larger than 68 bytes
 	/// (function_selector + tail_ptr + message_length).
-	static ParameterList failureParameters(bytes const _bytes);
+	static ParameterList failureParameters(bytes const& _bytes);
 
 	/// Returns _count parameters with their type set to ABIType::UnsignedDec
 	/// and their size set to 32 bytes.

test/libsolidity/util/TestFunctionCall.cpp

@@ -159,7 +159,7 @@ string TestFunctionCall::format(
 					BytesUtils::formatRawBytes(output, abiParams.value(), _linePrefix) :
 					BytesUtils::formatRawBytes(
 						output,
-						ContractABIUtils::defaultParameters(ceil(output.size() / 32)),
+						ContractABIUtils::defaultParameters((output.size() + 31) / 32),
 						_linePrefix
 					);
 
@@ -248,7 +248,7 @@ string TestFunctionCall::formatBytesParameters(
 		}
 		else
 		{
-			ParameterList defaultParameters = ContractABIUtils::defaultParameters(ceil(_bytes.size() / 32));
+			ParameterList defaultParameters = ContractABIUtils::defaultParameters((_bytes.size() + 31) / 32);
 
 			ContractABIUtils::overwriteParameters(_errorReporter, defaultParameters, _parameters);
 			os << BytesUtils::formatBytesRange(_bytes, defaultParameters, _highlight);