--- Source/JavaScriptCore/runtime/Options.cpp 2015-09-21 09:29:46.000000000 +0200 +++ Source/JavaScriptCore/runtime/Options.cpp 2015-09-30 12:32:25.447786694 +0200 @@ -610,7 +610,8 @@ case Options::Type::unsignedType: return m_entry.unsignedVal == other.m_entry.unsignedVal; case Options::Type::doubleType: - return (m_entry.doubleVal == other.m_entry.doubleVal) || (isnan(m_entry.doubleVal) && isnan(other.m_entry.doubleVal)); + return (m_entry.doubleVal == other.m_entry.doubleVal) || + (std::isnan(m_entry.doubleVal) && std::isnan(other.m_entry.doubleVal)); case Options::Type::int32Type: return m_entry.int32Val == other.m_entry.int32Val; case Options::Type::optionRangeType: