Subject: Re: bug#46111: Reverting fns.c hash function due to OpenBSD/SPARC64 compile breaking

From: Stefan Monnier <[email-masked]>
Date: Thu, 28 Jan 2021 10:44:09 -0500

>> - I'd guess that the bus error is due to alignment restrictions.
>>   What hardware is this running on?
> See the Subject: it's SPARC64.

I mean the actual hardware, not the architecture.

[ I know most RISC processors started with a restriction that they only
  allowed aligned memory accesses, but AFAIK they've changed stance
  since (IIUC the extra hardware can be very little, sometimes even less
  than the hardware that would be needed to implement the ad-hoc
  "support instructions" used to do the unaligned access as a sequence
  of instructions).
  It's one of the RISC simplifications that just didn't pan out.  ]

>> - AFAICT from the backtrace, `ptr` points to a plain normal ELisp
>>   string's content, yet these are supposed to be aligned, so what's
>>   going on here
> I wondered that myself.

And what did you conclude?  ;-)

        Stef