diff --git a/include/wx/univ/theme.h b/include/wx/univ/theme.h
index a5712c0c85..abc19d6631 100644
--- a/include/wx/univ/theme.h
+++ b/include/wx/univ/theme.h
@@ -14,6 +14,8 @@
 #ifndef _WX_UNIV_THEME_H_
 #define _WX_UNIV_THEME_H_
 
+#include "wx/string.h"
+
 // ----------------------------------------------------------------------------
 // wxTheme
 // ----------------------------------------------------------------------------
diff --git a/src/mgl/bitmap.cpp b/src/mgl/bitmap.cpp
index 2d7e61108f..a2f6ac217a 100644
--- a/src/mgl/bitmap.cpp
+++ b/src/mgl/bitmap.cpp
@@ -535,7 +535,7 @@ bitmap_t *wxBitmap::GetMGLbitmap_t() const
 
 // Convert wxColour into it's quantized value in lower-precision
 // pixel format (needed for masking by colour).
-wxColour wxBitmap::QuantizeColour(const wxColour& clr)
+wxColour wxBitmap::QuantizeColour(const wxColour& clr) const
 {
     pixel_format_t *pf = GetMGLbitmap_t()->pf;