bug#29866: 27.0.50; cl-loop: Calculate the array length just once

[Tino Calancha]

Stefan Monnier <monnier@IRO.UMontreal.CA> writes:

>> X-Debbugs-CC: monnier@iro.umontreal.ca
>
> Thanks.
>
>> It looks sensible to calculate the array length just once,
>> instead of recalculate it on each iteration:
>
> I tend to agree, but I don't know very much about the intended semantics
> of Common Lisp's `loop` macro, nor about cl-loop's implementation (tho
> I admit I did mess with it without being really sure what I was doing).
Ok, let's do it.
Pushed to master branch as commit 'cl-loop: Calculate the array length just 
once'
(bfca19e475c01f13dbacc7f8b7bb1aecf46cb7e4)