UPDATE 12/2/2010: The underlying linker issue is fixed by Apple in Xcode 3.2.5. Please upgrade to this version of Xcode.
UPDATE 8/30/2010: This issue has a workaround in the 11.1 Update 7 compiler, posted to Intel Registration center (https://registrationcenter.intel.com). ALL users with Xcode 3.2.2 and above should upgrade to 11.1 Update 7, 11.1.089 or greater.
UPDATE 5/7/2010: Xcode 3.2.2 and Xcode 3.2.3 and ifort are not compatible and can cause incorrect runtime results or segmentation faults. A possible workaround is to add -use-asm option to all compile and ifort link commands (see below). We are continuing to work with Apple to resolve this issue.
READ THE PROBLEM WRITEUP HERE: http://software.intel.com/en-us/articles/intel-fortran-for-mac-os-x-incompatible-with-xcode-322/
The current Intel Compilers 11.1 officially support Mac OS* X 10.6.2 and Xcode* 3.2.1.
Unofficial testing indicates that Mac OS* X 10.6.3 and Xcode* 3.2.1 appear to work together with the compiler, however this configuration is not OFFICIALLY supported at this time.
However, Mac OS* X 10.6.3 and Xcode* 3.2.2 combination with the Intel Compilers v11.1 have at least 1 known critical issue under investigation. At this time we do not recommend upgrading Xcode to 3.2.2 (or later). This version of Xcode includes a new build of gcc/g++ and it's libraries that appear to affect the Fortran runtime library. We will post more information as the investigation continues.
If you are seeing unusual behavior for your previously working applications after the Xcode 3.2.2 please add a reply to this thread. Particularly if you see any Intel C or C++ issues. So far we only have reports from Fortran users.
Ron W. Green, 28 April 2010