Frequently Asked Questions

General Obtaining GAP Installation Hardware/OS Usage Complaints Computing with GAP Programming GAP

4. Problems on Specific Hardware and Operating Systems (i.a. Windows and Macintosh)

4.8: Running GAP on an Intel Itanium (IA64) machine

There are currently problems running GAP4 on Intel Itanium processors, which can result in system crashes, or possibly other strange behaviour. It may be possible to run GAP correctly, if slowly, by disabling compiler optimisation, but this is not guaranteed.

For the technically inclined, the problem is the Itanium stack architecture, which uses a separate stack for register window overflows. The GAP garbage collector does not see that stack, and so may miss references to objects from C variables stored on it, resulting in live objects being incorrectly regarded as garbage and not preserved.

New! (Feb. 2008) An experimental patch is available, which appears to solve this problem. Itanium users are encouraged to try this patch and let us know how they get on.