On Fri, 3 Jun 2005, Leopold Toetsch wrote:

> Nick Glencross wrote:
> 
> > I fear that there may be some pointer alignment problems in hash because I'm
> > getting hangs which seem to be linked to finding strings in hash tables.
> > (That's pure conjecture)
> 
> I'm not aware of any problems with alignment in hash.c. *But* we will have
> troubles on that platform with doubles. Parrot PMCs are allocate off a big
> piece of mem. A PMC currently happens to be 24 bytes (on 32-bit) but only with
> the debug-ish version field compiled in. With an --optimze compiled parrot
> every second PMC would have unaligned doubles.

That's likely to cause a problem.  We've been recently hunting down odd 
alignment-related oddities on p5p.  As a first approximation, doubles need 
to be aligned at least on the boundaries given by Perl5's 
Config{'alignbytes'}. However, when those doubles are part of a structure, 
it apparently can get more confusing.  I don't think we sorted out all the 
possibilities, but Nick C. was the last one fiddling with it.

In the end, there may be no recourse other than using unions.

-- 
    Andy Dougherty              [EMAIL PROTECTED]

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