diff --git a/libsolidity/analysis/ReferencesResolver.cpp b/libsolidity/analysis/ReferencesResolver.cpp
index 30b06615e..451d6c93c 100644
--- a/libsolidity/analysis/ReferencesResolver.cpp
+++ b/libsolidity/analysis/ReferencesResolver.cpp
@@ -153,6 +153,11 @@ void ReferencesResolver::endVisit(Mapping const& _typeName)
 void ReferencesResolver::endVisit(ArrayTypeName const& _typeName)
 {
 	TypePointer baseType = _typeName.baseType().annotation().type;
+	if (!baseType)
+	{
+		solAssert(!m_errorReporter.errors().empty(), "");
+		return;
+	}
 	if (baseType->storageBytes() == 0)
 		fatalTypeError(_typeName.baseType().location(), "Illegal base type of storage size zero for array.");
 	if (Expression const* length = _typeName.length())
diff --git a/test/libsolidity/SolidityNameAndTypeResolution.cpp b/test/libsolidity/SolidityNameAndTypeResolution.cpp
index e8405281f..ee6a06338 100644
--- a/test/libsolidity/SolidityNameAndTypeResolution.cpp
+++ b/test/libsolidity/SolidityNameAndTypeResolution.cpp
@@ -2196,6 +2196,16 @@ BOOST_AUTO_TEST_CASE(array_copy_with_different_types_dynamic_static)
 	CHECK_ERROR(text, TypeError, "Type uint256[] storage ref is not implicitly convertible to expected type uint256[80] storage ref.");
 }
 
+BOOST_AUTO_TEST_CASE(array_of_undeclared_type)
+{
+	char const* text = R"(
+		contract c {
+			a[] public foo;
+		}
+	)";
+	CHECK_ERROR(text, DeclarationError, "Identifier not found or not unique.");
+}
+
 BOOST_AUTO_TEST_CASE(storage_variable_initialization_with_incorrect_type_int)
 {
 	char const* text = R"(