[plt-scheme] Re: A segmentation fault on OS X Intel

From: Noel Welsh (noelwelsh at gmail.com)
Date: Sun Jan 13 14:32:21 EST 2008

Matthew, you're a champion!

I'm assuming the BLAS routines in turn make use of the SSE operations
on Intel.  The Mac OS ABI suggests that these values should all be
16-byte aligned:


I don't know enough about the internals to know whether i) the BLAS
routines are indeed using SSE (though they really should) and ii) if
I'm looking at the right ABI (perhaps it should be the 64-bit one?)
I'll do a bit more digging.

It's a bit confusing that Apple don't like replacing documentation
when they change it, so it's easy to find docs that refer to
out-of-date information.


On Jan 13, 2008 7:06 PM, Matthew Flatt <mflatt at cs.utah.edu> wrote:
> After turning on 8-byte alignment for allocation via
>  #define ALIGN_DOUBLE
> in "newgc.c", then I'm not able to generate a crash.
> While 8-byte alignment isn't normally required for `double' arrays on
> x86 or Mac OS, maybe it's required for BLAS routines?
> Matthew

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