Re: [Caml-list] ocamlc, ocamlopt stackoverflow on list

[Gabriel Scherer <gabriel.scherer@gmail.com>]

My (entirely personal) understanding of the matter is that making
every part of the compiler tail-recursive is a pain in the ass, and
the kind of issues that never really stop happening (fix some case and
the stack will blow somewhere else). Given the potential decrease of
readability¹ that such changes may incur, there is even less incentive
to accept fixes on these issues.

¹: and eventual decrease of performance on small inputs, even if that
is less important in the compiler code

I would therefore suggest changing the generated code to look like the
following (modulo order-of-evaluation issues):

  let li = 29000::29001::...::[] in
  let li = 28000::28001::...::li in
  ...
  let li = 0::1::2::...::li in
  li

Remark: if the list is "quadratically too long", you may still
segfault because of the excessive nesting of (let .. in ..) in this
code. I'm unsure this could happen with a reasonable lower bound on
permitted stack usage, but this could be fixed as well with another
level of splitting: let li = (let li = ... in let li = ... in ... li)
in let li = ( ... ) in ...

On Fri, Nov 30, 2012 at 1:49 PM, Christophe Raffalli
<christophe.raffalli@univ-savoie.fr> wrote:
>
> On my machine (ocaml 3.12.1 on linux 64 bits) with unlimited stack,
> ocamlc and ocamlopt fails to compile a list constant of length 30000
> which is a problem in code generated by another program.