From 0a6c937dcbb3671e2fa5f6d7b50b5a909cf522d0 Mon Sep 17 00:00:00 2001
From: Yoichi Hirai <i@yoichihirai.com>
Date: Wed, 9 Nov 2016 14:14:18 +0100
Subject: codegen: shorten the overflow checking when converting into enums

---
 libsolidity/codegen/CompilerUtils.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

(limited to 'libsolidity')

diff --git a/libsolidity/codegen/CompilerUtils.cpp b/libsolidity/codegen/CompilerUtils.cpp
index 5e045996..ad155b13 100644
--- a/libsolidity/codegen/CompilerUtils.cpp
+++ b/libsolidity/codegen/CompilerUtils.cpp
@@ -661,7 +661,8 @@ void CompilerUtils::convertType(Type const& _typeOnStack, Type const& _targetTyp
 	if (targetTypeCategory == Type::Category::Enum)
 	{
 		EnumType const& enumType = dynamic_cast<decltype(enumType)>(_targetType);
-		m_context << u256(enumType.numberOfMembers()) << Instruction::DUP2 << Instruction::LT << Instruction::ISZERO;
+		solAssert(enumType.numberOfMembers() > 0, "empty enum should have caused a parser error.");
+		m_context << u256(enumType.numberOfMembers() - 1) << Instruction::DUP2 << Instruction::GT;
 		m_context.appendConditionalJumpTo(m_context.errorTag());
 	}
 }
-- 
cgit