- bool operator==(const wxBitmap& bitmap) { return m_refData == bitmap.m_refData; }
- bool operator!=(const wxBitmap& bitmap) { return m_refData != bitmap.m_refData; }
+ bool operator==(const wxBitmap& bitmap) const { return m_refData == bitmap.m_refData; }
+ bool operator!=(const wxBitmap& bitmap) const { return m_refData != bitmap.m_refData; }