Re: Trying to track down an alpha problem (may be in scm_ihashq).

[Dirk Herrmann]

On 14 Jun 2001, Rob Browning wrote:

> Here's my modified for debugging version of scm_ihashq
> 
>   unsigned int
>   scm_ihashq (SCM obj, unsigned int n)
>   {
>     unsigned int result;
>     unsigned long unpack = SCM_UNPACK(obj);
>     result = (SCM_UNPACK (obj) >> 1) % n;
>     fprintf(stderr, "scm_ihashq (%lu >> 1) %% %u -> %u\n", unpack, n, result);
>     fflush(stderr);
>     return result;
>   }
> 
> and at the point of failure, this prints:
> 
>   scm_ihashq (18446744073709551614 >> 1) % 31 -> 4294967295
> 
> Any help appreciated.

It seems that obj is an immediate number, more exactly the number -1.
This does not yet indicate any misbehaviour from guile's side.  It may
well be, however, that the fact that unsigned longs are 64 bits wide
causes problems elsewhere...

Best regards,
Dirk Herrmann