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This ABI is not
supported by all operating systems. gcc -mx32 HPPA 2.0 (‘ hppa2.0* ’, ‘ hppa64 ’) ¶ ‘ ABI=2.0w ’ The 2.0w ABI uses 64-bit limbs and pointers and is available on HP-UX 11 or
up. Applications must be compiled with gcc [built for 2.0w]
cc +DD64 ‘ ABI=2.0n ’ The 2.0n ABI means the 32-bit HPPA 1.0 ABI and all its normal calling
conventions, but with 64-bit instructions permitted within functions.