[CMake] CMAKE_OSX_ARCHITECTURES and 4-way universal binaries

[Sean McBride]

Hi all,

With 2.6.2, when I do 'C'onfigure, CMake gives me:

CMake Error at /Applications/CMake 2.6-2.app/Contents/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):
Utilities/kwsys/CMakeLists.txt:456 (CHECK_TYPE_SIZE)

If I ignore it, things seem to be OK, but this has been bugging me for a
while now.

After conferring with Mike Jackson, it turns out that if I change what I had:

SET (CMAKE_OSX_ARCHITECTURES "ppc;ppc64;i386;x86_64" CACHE STRING "Rogue")

to

SET (CMAKE_OSX_ARCHITECTURES "ppc;i386;x86_64;ppc64;" CACHE STRING "Rogue")

the error goes away. It surprises me that the order should be important.

I know what CMAKE_OSX_ARCHITECTURES is, but what is
CMAKE_TRY_COMPILE_OSX_ARCHITECTURES?

What's going on?

Thanks,

[Michael Jackson]

Post by Sean McBride
Hi all,
CMake Error at /Applications/CMake 2.6-2.app/Contents/share/cmake-2.6/
CHECK_TYPE_SIZE found different results, consider setting
CMAKE_OSX_ARCHITECTURES or CMAKE_TRY_COMPILE_OSX_ARCHITECTURES to one or no
architecture !
Utilities/kwsys/CMakeLists.txt:456 (CHECK_TYPE_SIZE)
If I ignore it, things seem to be OK, but this has been bugging me for a
while now.
SET (CMAKE_OSX_ARCHITECTURES "ppc;ppc64;i386;x86_64" CACHE STRING "Rogue")
to
SET (CMAKE_OSX_ARCHITECTURES "ppc;i386;x86_64;ppc64;" CACHE STRING "Rogue")
the error goes away. It surprises me that the order should be
important.
I know what CMAKE_OSX_ARCHITECTURES is, but what is
CMAKE_TRY_COMPILE_OSX_ARCHITECTURES?
What's going on?
Thanks,
--
____________________________________________________________
Rogue Research www.rogue-research.com
Mac Software Developer Montréal, Québec, Canada

Just to add some more background I traced the error down to the
Modules/CheckTypeSize.cmake file. At line 77 in that file there is a
check for a certain string within the binary file that gets compiled.

FILE(STRINGS "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/
CheckTypeSize.bin"
CMAKE_CHECKTYPESIZE_STRINGS LIMIT_COUNT 2 REGEX "INFO:sizeof")

I did a quick test on some of my own cmake code where I also do a
bunch of checks. One of those checks is the sizeof(ssize_t). When that
test is executed I get the following for the
CMAKE_CHECKTYPESIZE_STRINGS variable:

INFO:sizeof[00004]; INFO:sizeof[00008]

when I invoke cmake with the following:
DCMAKE_OSX_ARCHITECTURES:string='ppc;ppc64;i386;x86_64'

If I switch it around like Sean now has it I get:
-- Check size of size_t
-- CMAKE_CHECKTYPESIZE_STRINGS: INFO:sizeof[00004];INFO:sizeof[00004]

Which all kinda makes sense once I understood what the
FILE(STRINGS .. ) command was using for variables. But what is the
point of the code? I am not sure what sense it makes to run a
CheckTypeSize(ssize_t) on a binary that has 2 different address
models. I tried to work through some code to figure out the
ramifications but it is kinda late..


_________________________________________________________
Mike Jackson ***@bluequartz.net
BlueQuartz Software www.bluequartz.net
Principal Software Engineer Dayton, Ohio