Fix direct call to base class overloaded functions

Changelog.md

@@ -32,6 +32,7 @@ Bugfixes:
  * SMTChecker: SSA control-flow did not take into account state variables that were modified inside inlined functions that were called inside branches.
  * Type System: Use correct type name for contracts in event parameters when used in
    libraries. This affected code generation.
+ * Type System: Allow direct call to base class functions that have overloads.
  * Yul: Properly register functions and disallow shadowing between function variables and variables in the outside scope.
  * Code Generator: Fix initialization routine of uninitialized internal function pointers in constructor context.
 

libsolidity/ast/AST.cpp

@@ -215,16 +215,12 @@ vector<Declaration const*> const& ContractDefinition::inheritableMembers() const
 {
 	if (!m_inheritableMembers)
 	{
-		set<string> memberSeen;
 		m_inheritableMembers.reset(new vector<Declaration const*>());
 		auto addInheritableMember = [&](Declaration const* _decl)
 		{
 			solAssert(_decl, "addInheritableMember got a nullpointer.");
-			if (memberSeen.count(_decl->name()) == 0 && _decl->isVisibleInDerivedContracts())
-			{
-				memberSeen.insert(_decl->name());
+			if (_decl->isVisibleInDerivedContracts())
 				m_inheritableMembers->push_back(_decl);
-			}
 		};
 
 		for (FunctionDefinition const* f: definedFunctions())

test/libsolidity/semanticTests/functionCall/base_base_overload.sol

@@ -0,0 +1,50 @@
+contract BaseBase {
+	uint public x;
+	uint public y;
+	function init(uint a, uint b) public {
+		x = b;
+		y = a;
+	}
+	function init(uint a) public {
+		x = a + 1;
+	}
+}
+
+contract Base is BaseBase {
+	function init(uint a, uint b) public {
+		x = a;
+		y = b;
+	}
+	function init(uint a) public {
+		x = a;
+	}
+}
+
+contract Child is Base {
+	function cInit(uint c) public {
+		Base.init(c);
+	}
+	function cInit(uint c, uint d) public {
+		Base.init(c, d);
+	}
+	function bInit(uint c) public {
+		BaseBase.init(c);
+	}
+	function bInit(uint c, uint d) public {
+		BaseBase.init(c, d);
+	}
+}
+// ----
+// x() -> 0
+// y() -> 0
+// cInit(uint256): 2 ->
+// x() -> 2
+// y() -> 0
+// cInit(uint256,uint256): 3, 3 ->
+// x() -> 3
+// y() -> 3
+// bInit(uint256): 4 ->
+// x() -> 5
+// bInit(uint256,uint256): 9, 10 ->
+// x() -> 10
+// y() -> 9

test/libsolidity/semanticTests/functionCall/base_overload.sol

@@ -0,0 +1,29 @@
+contract Base {
+	uint public x;
+	uint public y;
+	function init(uint a, uint b) public {
+		x = a;
+		y = b;
+	}
+	function init(uint a) public {
+		x = a;
+	}
+}
+
+contract Child is Base {
+	function cInit(uint c) public {
+		Base.init(c);
+	}
+	function cInit(uint c, uint d) public {
+		Base.init(c, d);
+	}
+}
+// ----
+// x() -> 0
+// y() -> 0
+// cInit(uint256): 2 ->
+// x() -> 2
+// y() -> 0
+// cInit(uint256,uint256): 3, 3 ->
+// x() -> 3
+// y() -> 3