Complex in G77

[Toon Moene]

[ ... Sorry for missing this question early on ... ]

Tomas Restrepo wrote:

> I´ve just hot a quieck question regarding complex support on G77:
> The G77 docs I´ve got (the info pages on a redhat 6.1 system) imply that you
> can use the -fno-emulate-complex option to avoid complex emulation. It
> warns, though that it is problematic because of problems in the code
> generator in the compiler back end, at least until g77 2.7.22.
> Is that still the case?

It is a problem in all gcc and egcs releases before gcc-2.95.  Because
Red Hat 6.1 ships with egcs-1.1.2, you are not safe if you try
-fno-emulate-complex, *unless you have an independent method to check
that the code generated is OK*.

If you install gcc/g77-2.95.2 yourself, you'll automatically use
-fno-emulate-complex.  On 32 bit systems this should not give a problem
anymore; on 64 bit systems (like Alpha) you'll get an occasional
compiler abort (no incorrect code will be silently generated).

Hope this helps,

-- 
Toon Moene - mailto:toon@moene.indiv.nluug.nl - phoneto: +31 346 214290
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