Rainer Orth writes:
> Olaf Weber <olaf@xxxxxxxxxxxxxxxxxx> writes:
>> IIRC gcc 2.x defaults to o32 (and cannot do otherwise) while gcc 3.x
>> defaults to n32. You switch using options like '-mabi=64'.
> Wrong: GCC 2.x for IRIX 6 defaults to N32 (with N64 support available) and
> cannot support O32 without hacks (like configuring for mips-sgi-irix5).
> GCC 3.x is the same in this respect, but there's now a mips-sgi-irix6*o32
> configuration to support O32 on IRIX 6, which I hope to integrate into the
> common mips-sgi-irix6 configuration before GCC 3.4.
Ah. I remembered wrong then. (What I recall is that GCC 2.x took
quite some time to pick up support for n32 and I _thought_ this had
only been completed with the switch to 3.x.)
>> The native compiler (MIPSpro) has n32 as its default (set in
>> /etc/compiler.defaults) but also obeys the SGI_ABI environment
> Unfortunately, the default may also depend on the machine and compiler
> version used: e.g. R8000 machines defaulted to N64 with MIPSpro 7.3
> compilers ;-(
As far as I can tell they should have defaulted to mips4 N32 -- at
least when running IRIX 6.5 -- this is going by what the
to-be-installed /etc/compiler.defaults says. But the R8Ks were weird
beasts at the best of times.
> And there's also the issue of the ISA (instruction set
> architecture) used. See abi(5) and mips_ext(5) for the whole picture.
Yes, the /etc/compiler.defaulst specifies both ABI and ISA. Which
means that for maximum portability (meaning in this case the ability
to compile a program on one machine and run it on another) you should
explicitly specify both mips3 and N32.
> Rainer
--
Olaf Weber
(This space left blank for technical reasons.)
