I am trying to build a 3rd party open source project using MinGW. One of the dependencies is wxWidgets. When I try to make the project from MSYS I get a compiler error from /MinGW/msys/1.0/local/include/wx-2.8/wx/msw/private.h In function 'COLORREF wxColourToRGB(const wxColour&)': error: cannot convert 'RGB' to 'COLORREF {aka long unsigned in}' in return This is somewhat odd given that, according to Microsoft the RGB macro returns a COLORREF. In fact, looking in H:\MinGW\include I find wingdi.h with the following code #define RGB(r,g,b) ((COLORREF)((BYTE)(r)|((BYTE)(g) << 8)|((BYTE)(b) << 16))) What sort of thing would cause this error? Is there some way I can check to see if COLORREF and RGB are being included from wingdi.h and not somewhere else? Is that even worth checking? Specifications GCC version 4.7.2 wxWidgets version 2.8.12 (I'm new to C++ and MinGW specifically but generally computer and programming literate)