Re: buildd failure for sparc - floating point encoding?
Martin <inkubus@interalpha.co.uk> writes:
> Given that most of the machines sold by Sun are based on SPARC chips and
> most of the SPARC chips sold are sold by Sun I would guess the 'sun'
> setting is what you are after.
As daevm points out, the macros used are simply wrong. This should be
__sparc__, __MIPSEB__, &c. (You can check for many cases by looking
at GCC's machine files.) Macros like `sun' aren't defined in ISO C
mode -- it's `__sun__' -- and don't describe the hardware,
c.f. Solaris x86. I'm surprised CDF headers are that broken.
However, the package shouldn't be using its own version of CDF. It
should build against the Debian package, and a program doing CDF i/o
shouldn't care about this at all.
> In short (IIRC) most modern SPARC processors implement 32 and 64 bit
> IEEE floating point operations.
All SPARCs, surely?
> This is the same as some MIPS processors (I suspect the SGi
> setting), most PowerPCs (IBM-RS, Mac) and a host of other
> architectures.
The distinction is whether they're big or little endian. Probably the
majority of the architectures can actually be either.
> x86 chips (and IIRC the Alpha) support 80 bit IEEE operations, which is
> (I guess) why the have their own category.
[I don't think that's true for Alpha.]
> Althought the later example
> code doesn't seem to use this so it may be an encoding issue.
Assuming this is similar to HDF -- I don't know CDF -- it's probably a
question of the FP format written to binary files.
> If I was responsible for this code up stream I'd go for clarifying each
> of these categories down to exactly what standard each one is rather
> than what machines implement them. But then again I'm pedantic like
> that.
As above, it's not pedantic. Autoconf should be able to determine
what the FP format is, though I don't think there's an existing test;
it can definitely tell the byte sex. This must be sorted by the CDF
packages anyhow, and I assume they take into account the other
relevant format on S390.
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