Index access for bytesXX.

libsolidity/analysis/TypeChecker.cpp

@@ -1253,6 +1253,8 @@ bool TypeChecker::visit(MemberAccess const& _memberAccess)
 			arrayType.isDynamicallySized()
 		);
 	}
+	else if (exprType->category() == Type::Category::FixedBytes)
+		annotation.isLValue = false;
 
 	return false;
 }
@@ -1317,6 +1319,22 @@ bool TypeChecker::visit(IndexAccess const& _access)
 		}
 		break;
 	}
+	case Type::Category::FixedBytes:
+	{
+		FixedBytesType const& bytesType = dynamic_cast<FixedBytesType const&>(*baseType);
+		if (!index)
+			typeError(_access.location(), "Index expression cannot be omitted.");
+		else
+		{
+			expectType(*index, IntegerType(256));
+			if (auto integerType = dynamic_cast<IntegerConstantType const*>(type(*index).get()))
+				if (bytesType.numBytes() <= integerType->literalValue(nullptr))
+					typeError(_access.location(), "Out of bounds array access.");
+		}
+		resultType = make_shared<FixedBytesType>(1);
+		isLValue = false; // @todo this heavily depends on how it is embedded
+		break;
+	}
 	default:
 		fatalTypeError(
 			_access.baseExpression().location(),