From 11b4e7f7d8cf45be2717bb249cf966788f486ede Mon Sep 17 00:00:00 2001
From: Lu Guanqun <guanqun.lu@gmail.com>
Date: Tue, 10 Feb 2015 22:43:13 +0800
Subject: [PATCH] small fixes per chris's comments

---
 Types.cpp | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/Types.cpp b/Types.cpp
index dcc0738d7..5f573a6da 100644
--- a/Types.cpp
+++ b/Types.cpp
@@ -26,6 +26,8 @@
 #include <libsolidity/Types.h>
 #include <libsolidity/AST.h>
 
+#include <limits>
+
 using namespace std;
 
 namespace dev
@@ -322,13 +324,11 @@ TypePointer IntegerConstantType::binaryOperatorResult(Token::Value _operator, Ty
 			break;
 		case Token::Exp:
 			if (other.m_value < 0)
-				BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("exponent can't be negative"));
+				return TypePointer();
+			else if (other.m_value > std::numeric_limits<unsigned int>::max())
+				return TypePointer();
 			else
-			{
-				value = boost::multiprecision::powm(m_value, other.m_value, bigint(2) << 256);
-				if (value >= (bigint(1) << 256))
-					BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("exp result overflowed"));
-			}
+				value = boost::multiprecision::pow(m_value, other.m_value.convert_to<unsigned int>());
 			break;
 		default:
 			return TypePointer();