diff --git a/libsolidity/ast/ASTJsonConverter.cpp b/libsolidity/ast/ASTJsonConverter.cpp
index 6811d3e4e..51249f20d 100644
--- a/libsolidity/ast/ASTJsonConverter.cpp
+++ b/libsolidity/ast/ASTJsonConverter.cpp
@@ -129,7 +129,7 @@ string ASTJsonConverter::sourceLocationToString(SourceLocation const& _location)
 	return std::to_string(_location.start) + ":" + std::to_string(length) + ":" + std::to_string(sourceIndex);
 }
 
-string ASTJsonConverter::namePathToString(std::vector<ASTString> const& _namePath) const
+string ASTJsonConverter::namePathToString(std::vector<ASTString> const& _namePath)
 {
 	return boost::algorithm::join(_namePath, ".");
 }
@@ -171,7 +171,7 @@ void ASTJsonConverter::appendExpressionAttributes(
 	_attributes += exprAttributes;
 }
 
-Json::Value ASTJsonConverter::inlineAssemblyIdentifierToJson(pair<assembly::Identifier const* ,InlineAssemblyAnnotation::ExternalIdentifierInfo> _info)
+Json::Value ASTJsonConverter::inlineAssemblyIdentifierToJson(pair<assembly::Identifier const* ,InlineAssemblyAnnotation::ExternalIdentifierInfo> _info) const
 {
 	Json::Value tuple(Json::objectValue);
 	tuple["src"] = sourceLocationToString(_info.first->location);
diff --git a/libsolidity/ast/ASTJsonConverter.h b/libsolidity/ast/ASTJsonConverter.h
index 60c660c1f..9a886220f 100644
--- a/libsolidity/ast/ASTJsonConverter.h
+++ b/libsolidity/ast/ASTJsonConverter.h
@@ -120,7 +120,7 @@ private:
 		std::vector<std::pair<std::string, Json::Value>>&& _attributes
 	);
 	std::string sourceLocationToString(SourceLocation const& _location) const;
-	std::string namePathToString(std::vector<ASTString> const& _namePath) const;
+	static std::string namePathToString(std::vector<ASTString> const& _namePath);
 	static Json::Value idOrNull(ASTNode const* _pt)
 	{
 		return _pt ? Json::Value(nodeId(*_pt)) : Json::nullValue;
@@ -129,13 +129,13 @@ private:
 	{
 		return _node ? toJson(*_node) : Json::nullValue;
 	}
-	Json::Value inlineAssemblyIdentifierToJson(std::pair<assembly::Identifier const* , InlineAssemblyAnnotation::ExternalIdentifierInfo> _info);
-	std::string location(VariableDeclaration::Location _location);
-	std::string contractKind(ContractDefinition::ContractKind _kind);
-	std::string functionCallKind(FunctionCallKind _kind);
-	std::string literalTokenKind(Token::Value _token);
-	std::string type(Expression const& _expression);
-	std::string type(VariableDeclaration const& _varDecl);
+	Json::Value inlineAssemblyIdentifierToJson(std::pair<assembly::Identifier const* , InlineAssemblyAnnotation::ExternalIdentifierInfo> _info) const;
+	static std::string location(VariableDeclaration::Location _location);
+	static std::string contractKind(ContractDefinition::ContractKind _kind);
+	static std::string functionCallKind(FunctionCallKind _kind);
+	static std::string literalTokenKind(Token::Value _token);
+	static std::string type(Expression const& _expression);
+	static std::string type(VariableDeclaration const& _varDecl);
 	static int nodeId(ASTNode const& _node)
 	{
 		return _node.id();
@@ -151,8 +151,8 @@ private:
 		}
 		return tmp;
 	}
-	Json::Value typePointerToJson(TypePointer _tp);
-	Json::Value typePointerToJson(std::shared_ptr<std::vector<TypePointer>> _tps);
+	static Json::Value typePointerToJson(TypePointer _tp);
+	static Json::Value typePointerToJson(std::shared_ptr<std::vector<TypePointer>> _tps);
 	void appendExpressionAttributes(
 		std::vector<std::pair<std::string, Json::Value>> &_attributes,
 		ExpressionAnnotation const& _annotation
diff --git a/libsolidity/codegen/ExpressionCompiler.cpp b/libsolidity/codegen/ExpressionCompiler.cpp
index 631a25ff9..c94baa107 100644
--- a/libsolidity/codegen/ExpressionCompiler.cpp
+++ b/libsolidity/codegen/ExpressionCompiler.cpp
@@ -1819,7 +1819,7 @@ void ExpressionCompiler::setLValueToStorageItem(Expression const& _expression)
 	setLValue<StorageItem>(_expression, *_expression.annotation().type);
 }
 
-bool ExpressionCompiler::cleanupNeededForOp(Type::Category _type, Token::Value _op) const
+bool ExpressionCompiler::cleanupNeededForOp(Type::Category _type, Token::Value _op)
 {
 	if (Token::isCompareOp(_op) || Token::isShiftOp(_op))
 		return true;
diff --git a/libsolidity/codegen/ExpressionCompiler.h b/libsolidity/codegen/ExpressionCompiler.h
index 5f6c3d64d..cdfa096ea 100644
--- a/libsolidity/codegen/ExpressionCompiler.h
+++ b/libsolidity/codegen/ExpressionCompiler.h
@@ -119,7 +119,7 @@ private:
 
 	/// @returns true if the operator applied to the given type requires a cleanup prior to the
 	/// operation.
-	bool cleanupNeededForOp(Type::Category _type, Token::Value _op) const;
+	static bool cleanupNeededForOp(Type::Category _type, Token::Value _op);
 
 	/// @returns the CompilerUtils object containing the current context.
 	CompilerUtils utils();
diff --git a/test/libsolidity/AnalysisFramework.h b/test/libsolidity/AnalysisFramework.h
index f73f06c23..172ae01b9 100644
--- a/test/libsolidity/AnalysisFramework.h
+++ b/test/libsolidity/AnalysisFramework.h
@@ -59,8 +59,8 @@ protected:
 
 	void printErrors();
 
-	ContractDefinition const* retrieveContractByName(SourceUnit const& _source, std::string const& _name);
-	FunctionTypePointer retrieveFunctionBySignature(
+	static ContractDefinition const* retrieveContractByName(SourceUnit const& _source, std::string const& _name);
+	static FunctionTypePointer retrieveFunctionBySignature(
 		ContractDefinition const& _contract,
 		std::string const& _signature
 	);