[CMake] Problem with include directory ordering in wxWidgets_INCLUDE_DIRS

[Roger James]

Please can someone with access to the bug database raise this as a problem.

The CMake module FindwxWidgets.cmake sets up an a variable called  
wxWidgets_INCLUDE_DIRS which is intended to be used as the source of 
additional include directories to be searched by various build tools. 
The code that sets this up looks like this.

         # Set wxWidgets main include directory.
         IF(EXISTS ${WX_ROOT_DIR}/include/wx/wx.h)
           SET(wxWidgets_INCLUDE_DIRS ${WX_ROOT_DIR}/include)
         ELSE(EXISTS ${WX_ROOT_DIR}/include/wx/wx.h)
           DBG_MSG("wxWidgets_FOUND FALSE because 
WX_ROOT_DIR=${WX_ROOT_DIR} has no ${WX_ROOT_DIR}/include/wx/wx.h")
           SET(wxWidgets_FOUND FALSE)
         ENDIF(EXISTS ${WX_ROOT_DIR}/include/wx/wx.h)

         # Set wxWidgets lib setup include directory.
         IF(EXISTS ${WX_LIB_DIR}/${wxWidgets_CONFIGURATION}/wx/setup.h)
           LIST(APPEND wxWidgets_INCLUDE_DIRS
             ${WX_LIB_DIR}/${wxWidgets_CONFIGURATION})
         ELSE(EXISTS ${WX_LIB_DIR}/${wxWidgets_CONFIGURATION}/wx/setup.h)
           DBG_MSG("WXWIDGET_FOUND FALSE because 
${WX_LIB_DIR}/${wxWidgets_CONFIGURATION}/wx/setup.h does not exists.")
           SET(wxWidgets_FOUND FALSE)
         ENDIF(EXISTS ${WX_LIB_DIR}/${wxWidgets_CONFIGURATION}/wx/setup.h)

This results in the configuration specific (unicode/non-unicode) include 
directories being placed after the generic include directory in the 
list. This needs to be the other way round and can cause "duplicate 
manifest resource" problems when linking applications on windows visual 
studio platforms. This is caused by the fact that the file "rcdefs.h" 
exists in both the configuration specific include dir and in the generic 
include dir. However the version of rcdefs.h in the generic include dir 
is only intended to be used if configuration specific ones are not found.

The gory details are that the generic rcdefs.h does not contain a 
definition for WX_MSC_FULL_VER which is used to stop wxWidgets trying to 
link in its own manifest resource when newer versions of the of the 
Microsoft Compiler that provide their own manifests are being used.

I suggest that the two pieces of CMake code are swapped round and the 
SET and LIST commands modified as appropriate.

Having the include dirs in the current order may well cause other 
obscure problems as well.

Cheers,

Roger