[CMake] Testing the size of long throws error when more than one OS X Arch is passed

[Michael Jackson]

On Nov 17, 2009, at 6:45 PM, Sean McBride wrote:

> On 11/17/09 5:57 PM, Michael Jackson said:
>
>> cmake -DCMAKE_OSX_ARCHITECTURES='x86_64;i386' ../
>>
>> Will throw the following error:
>>
>> -- Check size of size_t
>> CMake Error at /Users/Shared/Toolkits/CMake-2.6.4/share/cmake-2.6/
>> Modules/CheckTypeSize.cmake:89 (MESSAGE):
>>  CHECK_TYPE_SIZE found different results, consider setting
>>  CMAKE_OSX_ARCHITECTURES or CMAKE_TRY_COMPILE_OSX_ARCHITECTURES to
>> one or no
>>  architecture !
>> Call Stack (most recent call first):
>>  ConfigureChecks.cmake:84 (CHECK_TYPE_SIZE)
>>  CMakeLists.txt:34 (INCLUDE)
>>
>> Which makes absolute sense. I am updating a legacy Expat build system
>> to CMake and just hit this when I was trying to automate some builds.
>> If I run cmake without specifying CMAKE_OSX_ARCHITECTURES variable.
>> What are others doing in this situation. Obviously something has to  
>> be
>> reworked on my end.
>
> Mike, are you reading my mind?  I just noticed that CMake has those  
> same
> errors building itself!  See:
> <http://public.kitware.com/Bug/view.php?id=9913>
>
> This is new in 2.8.
>
> --
> ____________________________________________________________
> Sean McBride, B. Eng                 sean at rogue-research.com
> Rogue Research                        www.rogue-research.com
> Mac Software Developer              Montréal, Québec, Canada
>
>

Maybe, that would be scary though. Basically I had to wrap the calls  
like this:

if (NOT APPLE)
     CHECK_TYPE_SIZE(long           MXA_SIZEOF_LONG)
     CHECK_TYPE_SIZE(size_t         MXA_SIZEOF_SIZE_T)
     CHECK_TYPE_SIZE(ssize_t        MXA_SIZEOF_SSIZE_T)
endif()

Then in the header file that gets configured I have this:

#if !defined(__APPLE__)
# define MXA_SIZEOF_CHAR   @MXA_SIZEOF_CHAR@
# define MXA_SIZEOF_SHORT  @MXA_SIZEOF_SHORT@
# define MXA_SIZEOF_INT    @MXA_SIZEOF_INT@
# define MXA_SIZEOF_LONG   @MXA_SIZEOF_LONG@
# define MXA_SIZEOF_FLOAT  @MXA_SIZEOF_FLOAT@
# define MXA_SIZEOF_DOUBLE @MXA_SIZEOF_DOUBLE@
#else
# define MXA_SIZEOF_CHAR   1
# define MXA_SIZEOF_SHORT  2
# define MXA_SIZEOF_INT    4
# if defined(__LP64__) && __LP64__
#  define MXA_SIZEOF_LONG  8
# else
#  define MXA_SIZEOF_LONG  4
# endif
# define MXA_SIZEOF_FLOAT  4
# define MXA_SIZEOF_DOUBLE 8
#endif

I think why it never gets hit is that everyone just builds CMake for a  
single arch, or they let CMake do the initial run, and then use the  
CMake-GUI to add an arch to the list. Just a guess. I guess someone  
can file a bug against cmake for that..

--
Mike Jackson <www.bluequartz.net>