choice of gcc version for Erlang on ARM/XScale/PXA

[Mikael Pettersson]

Marthin Laubscher writes:
 > It was all cross-compiled. I know erlc works on the gumstix itself, but I'm
 > pretty sure /lib/x/ebin/*.beam files were generated in the cross-compiling
 > environment. After fixing the float library problem, I didn't pick up any
 > other issues, but now I'm worried about what is going to still go wrong. Do
 > you think I should I leave the .beam files or try to get a version of GNU
 > make running on the gumstix and build them all there again. I've trimmed the
 > system to a minimum so making the .beam files will involve fiddling with the
 > makefiles again.

No, leave the .beam files alone. Rebuilding them on your gumstix will
almost certainly trigger the bug. I'm away from my ARM box so I can't
produce a nice test case right now, but the bug broke an integer shift
operation so that an 8-bit downshift of a bignum became an 8-bit upshift
instead. See what "16#001000000000 bsr 8." evaluates to in the shell.

 > Are you working on gumstix or another ARM/XScale/PXA implementation?

I'm using an XScale, actually an IXP420. I looked at the gumstix, but
it seemed to lack any disk I/O facilities, even USB2.0 based ones,
and given that limitation it seemed a bit overpriced.

 > My
 > gumstix app needs good float performance so I a little worried about running
 > without fpu. I'd love to learn about equally small alternatives that do
 > include a fpu option.

No XScale/PXA to date has an FPU, so if you need good f.p. performance
you should look elsewhere. www.arm.com does have cores with the VFP FPU,
but I don't know where one can buy systems based on them.

/Mikael