bug#17485: (srfi srfi-1) reduce-right does not scale, version 2.0.9

[Andy Wingo]

Hi,

On Tue 13 May 2014 12:47, David Kastrup <address@hidden> writes:

> The following code results in an error:
>
> (use-modules (srfi srfi-1))
> (reduce-right + 0 (make-list 10000 1))
>
> Backtrace:
> In srfi/srfi-1.scm:
>  379: 19 [recur (1 1 1 1 1 1 1 1 1 ...) (1 1 1 1 1 1 1 1 1 ...)]
>  379: 18 [recur (1 1 1 1 1 1 1 1 1 ...) (1 1 1 1 1 1 1 1 1 ...)]
>  379: 17 [recur (1 1 1 1 1 1 1 1 1 ...) (1 1 1 1 1 1 1 1 1 ...)]
>  379: 16 [recur (1 1 1 1 1 1 1 1 1 ...) (1 1 1 1 1 1 1 1 1 ...)]
>  379: 15 [recur (1 1 1 1 1 1 1 1 1 ...) (1 1 1 1 1 1 1 1 1 ...)]
>  379: 14 [recur (1 1 1 1 1 1 1 1 1 ...) (1 1 1 1 1 1 1 1 1 ...)]
>  379: 13 [recur (1 1 1 1 1 1 1 1 1 ...) (1 1 1 1 1 1 1 1 1 ...)]
>  379: 12 [recur (1 1 1 1 1 1 1 1 1 ...) (1 1 1 1 1 1 1 1 1 ...)]
>  379: 11 [recur (1 1 1 1 1 1 1 1 1 ...) (1 1 1 1 1 1 1 1 1 ...)]
>  379: 10 [recur (1 1 1 1 1 1 1 1 1 ...) (1 1 1 1 1 1 1 1 1 ...)]
>  379: 9 [recur (1 1 1 1 1 1 1 1 1 ...) (1 1 1 1 1 1 1 1 1 ...)]
>  379: 8 [recur (1 1 1 1 1 1 1 1 1 ...) (1 1 1 1 1 1 1 1 1 ...)]
>  379: 7 [recur (1 1 1 1 1 1 1 1 1 ...) (1 1 1 1 1 1 1 1 1 ...)]
>  379: 6 [recur (1 1 1 1 1 1 1 1 1 ...) (1 1 1 1 1 1 1 1 1 ...)]
>  379: 5 [recur (1 1 1 1 1 1 1 1 1 ...) (1 1 1 1 1 1 1 1 1 ...)]
>  379: 4 [recur (1 1 1 1 1 1 1 1 1 ...) (1 1 1 1 1 1 1 1 1 ...)]
>  379: 3 [recur (1 1 1 1 1 1 1 1 1 ...) (1 1 1 1 1 1 1 1 1 ...)]
>  379: 2 [recur (1 1 1 1 1 1 1 1 1 ...) (1 1 1 1 1 1 1 1 1 ...)]
>  379: 1 [recur (1 1 1 1 1 1 1 1 1 ...) (1 1 1 1 1 1 1 1 1 ...)]
>  379: 0 [recur (1 1 1 1 1 1 1 1 1 ...) (1 1 1 1 1 1 1 1 1 ...)]
>
> srfi/srfi-1.scm:379:31: In procedure recur:
> srfi/srfi-1.scm:379:31: Throw to key `vm-error' with args `(vm-run "VM: Stack 
> overflow" ())'.

On the 2.2 series this problem does not occur because there is no stack
limit.  Mark if you would like to fix this on 2.0 in a different way, go
ahead.  Otherwise we can close.

I think on 2.0 that this might be an OK workaround:

 (define (reduce-right f ridentity lst)
   (reduce f ridentity (reverse lst)))

Thoughts?

Andy