Support empty strings.

5 files changed, 22 insertions, 11 deletions

diff --git a/AST.cpp b/AST.cpp
index 593e0960..8174d138 100644
--- a/AST.cpp
+++ b/AST.cpp
@@ -339,7 +339,7 @@ void Literal::checkTypeRequirements()
 {
 	m_type = Type::forLiteral(*this);
 	if (!m_type)
-		BOOST_THROW_EXCEPTION(createTypeError("Literal value too large or too small."));
+		BOOST_THROW_EXCEPTION(createTypeError("Literal value too large."));
 }
 
 }
diff --git a/Compiler.cpp b/Compiler.cpp
index 940a5e70..92d574fb 100644
--- a/Compiler.cpp
+++ b/Compiler.cpp
@@ -135,7 +135,7 @@ unsigned Compiler::appendCalldataUnpacker(FunctionDefinition const& _function, b
 	for (ASTPointer<VariableDeclaration> const& var: _function.getParameters())
 	{
 		unsigned const numBytes = var->getType()->getCalldataEncodedSize();
-		if (numBytes == 0 || numBytes > 32)
+		if (numBytes > 32)
 			BOOST_THROW_EXCEPTION(CompilerError()
 								  << errinfo_sourceLocation(var->getLocation())
 								  << errinfo_comment("Type " + var->getType()->toString() + " not yet supported."));
@@ -156,7 +156,7 @@ void Compiler::appendReturnValuePacker(FunctionDefinition const& _function)
 	{
 		Type const& paramType = *parameters[i]->getType();
 		unsigned numBytes = paramType.getCalldataEncodedSize();
-		if (numBytes == 0 || numBytes > 32)
+		if (numBytes > 32)
 			BOOST_THROW_EXCEPTION(CompilerError()
 								  << errinfo_sourceLocation(parameters[i]->getLocation())
 								  << errinfo_comment("Type " + paramType.toString() + " not yet supported."));
diff --git a/CompilerUtils.cpp b/CompilerUtils.cpp
index 0ee4a53c..9f474896 100644
--- a/CompilerUtils.cpp
+++ b/CompilerUtils.cpp
@@ -33,9 +33,14 @@ namespace solidity
 
 void CompilerUtils::loadFromMemory(unsigned _offset, unsigned _bytes, bool _leftAligned, bool _fromCalldata)
 {
+	if (_bytes == 0)
+	{
+		m_context << u256(0);
+		return;
+	}
 	eth::Instruction load = _fromCalldata ? eth::Instruction::CALLDATALOAD : eth::Instruction::MLOAD;
-	if (asserts(0 < _bytes && _bytes <= 32))
-		BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Memory load of 0 or more than 32 bytes requested."));
+	if (asserts(_bytes <= 32))
+		BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Memory load of more than 32 bytes requested."));
 	if (_bytes == 32)
 		m_context << u256(_offset) << load;
 	else
@@ -53,8 +58,13 @@ void CompilerUtils::loadFromMemory(unsigned _offset, unsigned _bytes, bool _left
 
 void CompilerUtils::storeInMemory(unsigned _offset, unsigned _bytes, bool _leftAligned)
 {
-	if (asserts(0 < _bytes && _bytes <= 32))
-		BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Memory store of 0 or more than 32 bytes requested."));
+	if (_bytes == 0)
+	{
+		m_context << eth::Instruction::POP;
+		return;
+	}
+	if (asserts(_bytes <= 32))
+		BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Memory store of more than 32 bytes requested."));
 	if (_bytes != 32 && !_leftAligned)
 		// shift the value accordingly before storing
 		m_context << (u256(1) << ((32 - _bytes) * 8)) << eth::Instruction::MUL;
diff --git a/Token.h b/Token.h
index f9ded311..21b74ece 100644
--- a/Token.h
+++ b/Token.h
@@ -269,6 +269,7 @@ namespace solidity
 	K(ADDRESS, "address", 0)                                           \
 	K(BOOL, "bool", 0)                                                 \
 	K(STRING_TYPE, "string", 0)                                        \
+	K(STRING0, "string0", 0)                                           \
 	K(STRING1, "string1", 0)                                           \
 	K(STRING2, "string2", 0)                                           \
 	K(STRING3, "string3", 0)                                           \
diff --git a/Types.cpp b/Types.cpp
index 543c27c2..00e530c3 100644
--- a/Types.cpp
+++ b/Types.cpp
@@ -53,8 +53,8 @@ shared_ptr<Type const> Type::fromElementaryTypeName(Token::Value _typeToken)
 		return make_shared<IntegerType const>(0, IntegerType::Modifier::ADDRESS);
 	else if (_typeToken == Token::BOOL)
 		return make_shared<BoolType const>();
-	else if (Token::STRING1 <= _typeToken && _typeToken <= Token::STRING32)
-		return make_shared<StaticStringType const>(int(_typeToken) - int(Token::STRING1) + 1);
+	else if (Token::STRING0 <= _typeToken && _typeToken <= Token::STRING32)
+		return make_shared<StaticStringType const>(int(_typeToken) - int(Token::STRING0));
 	else
 		BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Unable to convert elementary typename " +
 																		 std::string(Token::toString(_typeToken)) + " to type."));
@@ -199,14 +199,14 @@ const MemberList IntegerType::AddressMemberList =
 
 shared_ptr<StaticStringType> StaticStringType::smallestTypeForLiteral(string const& _literal)
 {
-	if (0 < _literal.length() && _literal.length() <= 32)
+	if (_literal.length() <= 32)
 		return make_shared<StaticStringType>(_literal.length());
 	return shared_ptr<StaticStringType>();
 }
 
 StaticStringType::StaticStringType(int _bytes): m_bytes(_bytes)
 {
-	if (asserts(m_bytes > 0 && m_bytes <= 32))
+	if (asserts(m_bytes >= 0 && m_bytes <= 32))
 		BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Invalid byte number for static string type: " +
 																		 dev::toString(m_bytes)));
 }