What are the preconditions of newArray#

Johan Tibell johan.tibell at gmail.com
Mon Aug 22 09:43:29 CEST 2011


On Mon, Aug 22, 2011 at 5:55 AM, Edward Z. Yang <ezyang at mit.edu> wrote:
> stg_newArrayzh in rts/PrimOps.cmm doesn't appear to give any indication,
> so this might be a good patch to add.  But I'm curious: what would
> allocating Array#s of size 0 do? Null pointers? That sounds dangerous...

I would imagine that a zero sized array would be a StgArrPtrs header
with its size field set to 0. It's not a very useful thing to have, I
admit. If someone (Simon?) can confirm that we don't intend to support
zero-length array I'll push a patch that adds a comment.

Johan



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