From 82f5763e7afa498f891e9d41b30278c4482ddb8b Mon Sep 17 00:00:00 2001
From: Anurag Dashputre <anurag4u80@gmail.com>
Date: Sat, 1 Dec 2018 22:50:56 +0530
Subject: [PATCH] Fix internal compiler error for unimplemented base contract
 function.

---
 Changelog.md                                         |  1 +
 libsolidity/ast/Types.cpp                            |  3 ++-
 .../syntaxTests/unimplemented_super_function.sol     |  8 ++++++++
 .../unimplemented_super_function_derived.sol         | 12 ++++++++++++
 4 files changed, 23 insertions(+), 1 deletion(-)
 create mode 100644 test/libsolidity/syntaxTests/unimplemented_super_function.sol
 create mode 100644 test/libsolidity/syntaxTests/unimplemented_super_function_derived.sol

diff --git a/Changelog.md b/Changelog.md
index 72d51bff9..5df412ca8 100644
--- a/Changelog.md
+++ b/Changelog.md
@@ -25,6 +25,7 @@ Bugfixes:
  * Type Checker: Disallow struct return types for getters of public state variables unless the new ABI encoder is active.
  * Type Checker: Fix internal compiler error when a field of a struct used as a parameter in a function type has a non-existent type.
  * Type Checker: Disallow functions ``sha3`` and ``suicide`` also without a function call.
+ * Type Checker: Fix internal compiler error with ``super`` when base contract function is not implemented.
  * Type Checker: Fixed internal error when trying to create abstract contract in some cases.
  * Type Checker: Fixed internal error related to double declaration of events.
  * Type Checker: Disallow inline arrays of mapping type.
diff --git a/libsolidity/ast/Types.cpp b/libsolidity/ast/Types.cpp
index 16e9cf892..6cadb5f33 100644
--- a/libsolidity/ast/Types.cpp
+++ b/libsolidity/ast/Types.cpp
@@ -1943,8 +1943,9 @@ MemberList::MemberMap ContractType::nativeMembers(ContractDefinition const* _con
 		for (ContractDefinition const* base: bases | boost::adaptors::sliced(1, bases.size()))
 			for (FunctionDefinition const* function: base->definedFunctions())
 			{
-				if (!function->isVisibleInDerivedContracts())
+				if (!function->isVisibleInDerivedContracts() || !function->isImplemented())
 					continue;
+
 				auto functionType = make_shared<FunctionType>(*function, true);
 				bool functionWithEqualArgumentsFound = false;
 				for (auto const& member: members)
diff --git a/test/libsolidity/syntaxTests/unimplemented_super_function.sol b/test/libsolidity/syntaxTests/unimplemented_super_function.sol
new file mode 100644
index 000000000..356727ae4
--- /dev/null
+++ b/test/libsolidity/syntaxTests/unimplemented_super_function.sol
@@ -0,0 +1,8 @@
+contract a {
+    function f() public;
+}
+contract b is a {
+    function f() public { super.f(); }
+}
+// ----
+// TypeError: (84-91): Member "f" not found or not visible after argument-dependent lookup in contract super b.
diff --git a/test/libsolidity/syntaxTests/unimplemented_super_function_derived.sol b/test/libsolidity/syntaxTests/unimplemented_super_function_derived.sol
new file mode 100644
index 000000000..88acbdf0d
--- /dev/null
+++ b/test/libsolidity/syntaxTests/unimplemented_super_function_derived.sol
@@ -0,0 +1,12 @@
+contract a {
+    function f() public;
+}
+contract b is a {
+    function f() public { super.f(); }
+}
+contract c is a,b {
+    // No error here.
+    function f() public { super.f(); }
+}
+// ----
+// TypeError: (84-91): Member "f" not found or not visible after argument-dependent lookup in contract super b.