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Applications must be compiled with gcc -mlp64
cc +DD64 On other IA-64 systems, GNU/Linux for instance, ‘ ABI=64 ’ is the only
choice. MIPS under IRIX 6 (‘ mips*-*-irix[6789] ’) ¶ IRIX 6 always has a 64-bit MIPS 3 or better CPU, and supports ABIs o32, n32,
and 64. n32 or 64 are recommended, and GMP performance will be the same in
each.