Re: Problem with Excel import on ARM

[Wookey <wookey aleph1 co uk>]

+++ Morten Welinder [04-05-05 12:40 -0400]:
> Please let me know what you get...  If you don't get anything like the
> above, perhaps you know of a reference that tells the layout of doubles
> on ARM?

OK - this confirms the dignosis that the current ARM-linux ABI used mixed-endian floats:
http://lists.debian.org/debian-arm/2003/10/msg00033.html 

And to save you following that link:
> > Does ARM store doubles in a non-IEEE way?  Is it secretly big-endian for
> > its float/double emulation, and little-endian for ints?  What else could
> > be wrong with mozilla's assumptions about double format?
>
> I suspect you've found mozilla's bug. ARM doubles are mixed endian.
>
> IIRC the bits in the 32 bit words are stored little endian as you would
> expect, but the words are ordered big endian in memory.
> (At least for the ABI that Debian uses)
>
> (I will be corrected if I have this the wrong way round)

> Also IIRC this is perfectly legal IEEE, just mighty odd.

That's correct, and it's true for all ARM platforms I'm aware of, so
use of the __arm__ predefine is valid for any special handling of this.

--------------

I think this is due to change soon (i.e sometime in the next year) when ARM
gcc moves to soft-float by default, and whilst we are breaking ABIs a less
peculiar double format will be adopted, but in the meatime this is what
everything is using.

Wookey
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