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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. The default is n32. ‘ ABI=o32 ’ The o32 ABI is 32-bit pointers and integers, and no 64-bit operations.