Re: GNAT on armhf

[Ludovic Brenta <ludovic@ludovic-brenta.org>]

Tero Koskinen writes:
> I don't remember any calling convention specific things in GNAT or its
> runtime, so is it just a simple matter of compiling the compiler for
> armhf?

There is a specific calling convention, in particular as regards
floating point registers, but I think the compiler deals with that by
itself.  Also, IIUC, the ABI for ARMv7 supports only the Thumb
instruction format whereas ARMv6 allows both Thumb and the older, less
densely packed, format.  It is this calling convention and format that
prevent software compiled for armhf from running on ARMv6 hardware.  So,
I think what's needed at this point is "just" someone to bootstrap the
compiler on the appropriate hardware.  If you could do that you'd
deserve a star on the walk of fame :) I haven't really researched this
issue, so take everything I said with a kilogram of salt, as I may be
entirely wrong.

After this bootstrapping, it would be nice to tune Ada.Numerics to use
BLAS and LAPACK compiled with hardware floating point.

Thanks for your offer.  I appreciate it because we're not short of
people with ideas, we're short of experts with free time and energy :)

-- 
Ludovic Brenta.