XSB on 64-bit platforms

XSB has been tested on 64-bit Debian linux, and runs well there, overall. However, there are a few minor details that have not been worked out at the time of release of Version 3.0 ^2.1. When XSB is compiled in 64-bit mode, full floating point precesion is not yet available as XSB uses 3 of the 64 bits for a tag. Also, the sockets library may have problems in Version 3.0. If any of these limitations prove a problem, please contact xsb-development@lists.sourceforge.net.

Typically, if the 64-bit system generates 32-bit code by default, XSB will run just as in 32-bit mode (including 64-bit floats). 64-bit compilation can be forced for XSB by configuring with the option -with-bits64, and in a similar manner 32-bit compilation can be forced with the option -with-bits32. The latter option may be useful for linking XSB into an application that is not yet safe for 64 bits. Users who employ either option should be aware of issues that may arise when linking XSB to external C code.

• When XSB calls C code the C file must have been compiled with the same memory option as XSB. This is done automatically if the C file is compiled via a call from XSB's compiler, but must be handled by the user otherwise. For instance, if XSB were configured -with-bits32 on a 64-bit machine defaulting to 64-bits, then C files called by XSB require the -m32 option in gcc.
• The appropriate memory option must be used when embedding XSB into a C or Java process. For instance, if a XSB is to be linked into a 32-bit application on a 64-bit platform defaulting to 64-bits, XSB must be configured -with-bits32, and the linking of xsb.o/so to the calling program must specify -m32.